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7dff1cba62
this option was never used and there is also no use to set other columns but the first as the primary key. as a result, access methods to the key do not need to compute key positions, and they work faster. git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@5711 6c8d7289-2bf4-0310-a012-ef5d649a1542
1632 lines
75 KiB
Java
1632 lines
75 KiB
Java
// kelondroTree.java
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// -----------------------
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// part of The Kelondro Database
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// (C) by Michael Peter Christen; mc@yacy.net
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// first published on http://www.anomic.de
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// Frankfurt, Germany, 2004
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// last major change: 07.02.2005
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//
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 2 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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/*
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This class extends the kelondroRecords and adds a tree structure
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*/
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package de.anomic.kelondro.table;
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import java.io.BufferedReader;
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import java.io.File;
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import java.io.FileReader;
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import java.io.IOException;
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import java.io.RandomAccessFile;
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import java.util.ArrayList;
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import java.util.Comparator;
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import java.util.HashSet;
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import java.util.Iterator;
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import java.util.LinkedList;
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import java.util.List;
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import java.util.Map;
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import java.util.StringTokenizer;
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import java.util.TreeMap;
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import java.util.TreeSet;
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import java.util.Vector;
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import java.util.logging.Logger;
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import de.anomic.kelondro.index.Row;
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import de.anomic.kelondro.index.RowCollection;
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import de.anomic.kelondro.index.ObjectIndex;
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import de.anomic.kelondro.index.Row.Entry;
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import de.anomic.kelondro.order.ByteOrder;
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import de.anomic.kelondro.order.CloneableIterator;
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import de.anomic.kelondro.order.NaturalOrder;
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import de.anomic.kelondro.util.kelondroException;
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import de.anomic.kelondro.util.Log;
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public class Tree extends CachedRecords implements ObjectIndex {
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// logging (This probably needs someone to initialize the java.util.logging.* facilities);
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public static final Logger log = Logger.getLogger("KELONDRO");
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// define the Over-Head-Array
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protected static final short thisOHBytes = 2; // our record definition of two bytes
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protected static final short thisOHHandles = 3; // and three handles overhead
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protected static final short thisFHandles = 1; // file handles: one for a root pointer
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// define pointers for OH array access
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protected static final int magic = 0; // pointer for OHByte-array: marker for Node purpose; defaults to 1
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protected static final int balance = 1; // pointer for OHByte-array: balance value of tree node; balanced = 0
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protected static final int parent = 0; // pointer for OHHandle-array: handle()-Value of parent Node
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protected static final int leftchild = 1; // pointer for OHHandle-array: handle()-Value of left child Node
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protected static final int rightchild = 2; // pointer for OHHandle-array: handle()-Value of right child Node
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protected static final int root = 0; // pointer for FHandles-array: pointer to root node
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// class variables
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private final Search writeSearchObj = new Search();
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protected Comparator<String> loopDetectionOrder;
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protected int readAheadChunkSize = 100;
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protected long lastIteratorCount = readAheadChunkSize;
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/**
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* Deprecated Class. Please use kelondroEcoTable instead
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*/
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@Deprecated
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public Tree(final File file, final boolean useNodeCache, final long preloadTime, final Row rowdef) throws IOException {
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this(file, useNodeCache, preloadTime, rowdef, rowdef.columns() /* txtProps */, 80 /* txtPropWidth */);
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}
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@Deprecated
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public Tree(final File file, final boolean useNodeCache, final long preloadTime, final Row rowdef, final int txtProps, final int txtPropsWidth) throws IOException {
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// opens an existing tree file or creates a new tree file
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super(file, useNodeCache, preloadTime,
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thisOHBytes, thisOHHandles, rowdef,
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thisFHandles, txtProps, txtPropsWidth);
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if (!fileExisted) {
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// create new file structure
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setHandle(root, null); // define the root value
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}
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super.setLogger(log);
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this.loopDetectionOrder = new ByteOrder.StringOrder(rowdef.objectOrder);
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}
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@Deprecated
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public static final Tree open(final File file, final boolean useNodeCache, final long preloadTime, final Row rowdef, final int txtProps, final int txtPropsWidth) {
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// opens new or existing file; in case that any error occur the file is deleted again and it is tried to create the file again
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// if that fails, the method returns null
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try {
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return new Tree(file, useNodeCache, preloadTime, rowdef, txtProps, txtPropsWidth);
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} catch (final IOException e) {
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file.delete();
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try {
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return new Tree(file, useNodeCache, preloadTime, rowdef, txtProps, txtPropsWidth);
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} catch (final IOException ee) {
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log.severe("cannot open or create file " + file.toString());
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e.printStackTrace();
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ee.printStackTrace();
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return null;
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}
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}
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}
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public void clear() throws IOException {
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super.clear();
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setHandle(root, null);
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}
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private void commitNode(final Node n) throws IOException {
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//kelondroHandle left = n.getOHHandle(leftchild);
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//kelondroHandle right = n.getOHHandle(rightchild);
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n.commit();
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}
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// the has-property in kelondroTree should not be used, because it has the effect of doubling the IO activity in case that
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// the result is 'true'. Whenever possible, please use the get method, store the result in a dummy value and test the result
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// by comparing it with null.
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public boolean has(final byte[] key) {
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boolean result;
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synchronized (writeSearchObj) {
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try {
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writeSearchObj.process(key);
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result = writeSearchObj.found();
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} catch (final IOException e) {
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result = false;
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}
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}
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return result;
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}
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// Returns the value to which this map maps the specified key.
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public Row.Entry get(final byte[] key) throws IOException {
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Row.Entry result;
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synchronized (writeSearchObj) {
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writeSearchObj.process(key);
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if (writeSearchObj.found()) {
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result = row().newEntry(writeSearchObj.getMatcher().getValueRow());
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} else {
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result = null;
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}
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}
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return result;
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}
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public ArrayList<RowCollection> removeDoubles() {
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// this data structure cannot have doubles; return empty array
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return new ArrayList<RowCollection>();
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}
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public class Search {
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// a search object combines the results of a search in the tree, which are
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// - the searched object is found, an index pointing to the node can be returned
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// - the object was not found, an index pointing to an appropriate possible parent node
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// can be returned, together with the information wether the new key shall
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// be left or right child.
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private CacheNode thenode, parentnode;
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private boolean found; // property if node was found
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private byte child; // -1: left child; 0: root node; 1: right child
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// temporary variables
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private RecordHandle thisHandle;
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String keybuffer;
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protected Search() {
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}
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protected void process(final byte[] key) throws IOException {
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// searchs the database for the key and stores the result in the thisHandle
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// if the key was found, then found=true, thisHandle and leftchild is set;
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// else found=false and thisHandle and leftchild is undefined
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thisHandle = getHandle(root);
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parentnode = null;
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if (key == null) {
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throw new kelondroException("startet search process with key == null");
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/*
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child = 0;
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if (thisHandle == null) {
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thenode = null;
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found = false;
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} else {
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thenode = getNode(thisHandle, null, 0);
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found = true;
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}
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return;
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*/
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}
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thenode = null;
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child = 0;
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found = false;
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int c;
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final TreeSet<String> visitedNodeKeys = new TreeSet<String>(loopDetectionOrder); // to detect loops
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// System.out.println("Starting Compare Loop in Database " + filename); // debug
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while (thisHandle != null) {
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try {
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parentnode = thenode;
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thenode = new CacheNode(thisHandle, thenode, (child == -1) ? leftchild : rightchild, true);
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} catch (final IllegalArgumentException e) {
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logWarning("kelondroTree.Search.process: fixed a broken handle");
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found = false;
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return;
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}
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if (thenode == null) throw new kelondroException(filename, "kelondroTree.Search.process: thenode==null");
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keybuffer = new String(thenode.getKey());
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if (keybuffer == null) {
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// this is an error. distinguish two cases:
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// 1. thenode is a leaf node. Then this error can be fixed if we can consider this node as a good node to be replaced with a new value
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// 2. thenode is not a leaf node. An exception must be thrown
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if ((thenode.getOHHandle(leftchild) == null) && (thenode.getOHHandle(rightchild) == null)) {
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// case 1: recover
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deleteNode(thisHandle);
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thenode = parentnode;
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found = false;
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return;
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} else {
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// case 2: fail
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throw new kelondroException("found key during search process with key == null");
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}
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}
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if (visitedNodeKeys.contains(keybuffer)) {
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// we have loops in the database.
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// to fix this, all affected nodes must be patched
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thenode.setOHByte(magic, (byte) 1);
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thenode.setOHByte(balance, (byte) 0);
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thenode.setOHHandle(parent, null);
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thenode.setOHHandle(leftchild, null);
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thenode.setOHHandle(rightchild, null);
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thenode.commit();
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logWarning("kelondroTree.Search.process: database contains loops; the loop-nodes have been auto-fixed");
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found = false;
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return;
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}
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// System.out.println("Comparing key = '" + new String(key) + "' with '" + otherkey + "':"); // debug
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c = row().objectOrder.compare(key, keybuffer.getBytes());
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// System.out.println(c); // debug
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if (c == 0) {
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found = true;
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// System.out.println("DEBUG: search for " + new String(key) + " ended with status=" + ((found) ? "found" : "not-found") + ", node=" + ((thenode == null) ? "NULL" : thenode.toString()) + ", parent=" + ((parentnode == null) ? "NULL" : parentnode.toString()));
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return;
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} else if (c < 0) {
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child = -1;
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thisHandle = thenode.getOHHandle(leftchild);
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} else {
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child = 1;
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thisHandle = thenode.getOHHandle(rightchild);
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}
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visitedNodeKeys.add(keybuffer);
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}
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// System.out.println("DEBUG: search for " + new String(key) + " ended with status=" + ((found) ? "found" : "not-found") + ", node=" + ((thenode == null) ? "NULL" : thenode.toString()) + ", parent=" + ((parentnode == null) ? "NULL" : parentnode.toString()));
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// we reached a node where we must insert the new value
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// the parent of this new value can be obtained by getParent()
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// all values are set, just return
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}
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public boolean found() {
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return found;
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}
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public CacheNode getMatcher() {
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if (found) return thenode;
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throw new IllegalArgumentException("wrong access of matcher");
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}
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public CacheNode getParent() {
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if (found) return parentnode;
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return thenode;
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}
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public boolean isRoot() {
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if (found) throw new IllegalArgumentException("wrong access of isRoot");
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return (child == 0);
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}
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public boolean isLeft() {
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if (found) throw new IllegalArgumentException("wrong access of leftchild");
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return (child == -1);
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}
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public boolean isRight() {
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if (found) throw new IllegalArgumentException("wrong access of leftchild");
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return (child == 1);
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}
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}
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public synchronized boolean isChild(final Node childn, final Node parentn, final int child) {
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if (childn == null) throw new IllegalArgumentException("isLeftChild: Node parameter is NULL");
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final RecordHandle lc = parentn.getOHHandle(child);
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if (lc == null) return false;
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return (lc.equals(childn.handle()));
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}
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public synchronized void put(final List<Entry> rows) throws IOException {
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final Iterator<Entry> i = rows.iterator();
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while (i.hasNext()) put(i.next());
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}
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public void put(final Row.Entry newrow) throws IOException {
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replace(newrow);
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}
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public Row.Entry replace(final Row.Entry newrow) throws IOException {
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assert (newrow != null);
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assert (newrow.columns() == row().columns());
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assert (!(Log.allZero(newrow.getPrimaryKeyBytes())));
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assert newrow.objectsize() <= super.row().objectsize;
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// Associates the specified value with the specified key in this map
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Row.Entry result = null;
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//writeLock.stay(2000, 1000);
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// first try to find the key element in the database
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synchronized(writeSearchObj) {
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writeSearchObj.process(newrow.getColBytes(0));
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if (writeSearchObj.found()) {
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// a node with this key exist. simply overwrite the content and return old content
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final Node e = writeSearchObj.getMatcher();
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result = row().newEntry(e.getValueRow());
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e.setValueRow(newrow.bytes());
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commitNode(e);
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} else if (writeSearchObj.isRoot()) {
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// a node with this key does not exist and there is no node at all
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// this therefore creates the root node if an only if there was no root Node yet
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if (getHandle(root) != null)
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throw new kelondroException(filename, "tried to create root node twice");
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// we dont have any Nodes in the file, so start here to create one
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final Node e = new CacheNode(newrow.bytes());
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// write the propetries
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e.setOHByte(magic, (byte) 1);
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e.setOHByte(balance, (byte) 0);
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e.setOHHandle(parent, null);
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e.setOHHandle(leftchild, null);
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e.setOHHandle(rightchild, null);
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// do updates
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e.commit();
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setHandle(root, e.handle());
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result = null;
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} else {
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// a node with this key does not exist
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// this creates a new node if there is already at least a root node
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// to create the new node, it is necessary to assign it to a parent
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// it must also be defined weather this new node is a left child of the
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// parent or not. It is checked if the parent node already has a child on
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// that side, but not if the assigned position is appropriate.
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// create new node and assign values
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CacheNode parentNode = writeSearchObj.getParent();
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CacheNode theNode = new CacheNode(newrow.bytes());
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theNode.setOHByte(0, (byte) 1); // fresh magic
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theNode.setOHByte(1, (byte) 0); // fresh balance
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theNode.setOHHandle(parent, parentNode.handle());
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theNode.setOHHandle(leftchild, null);
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theNode.setOHHandle(rightchild, null);
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theNode.commit();
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// check consistency and link new node to parent node
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byte parentBalance;
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if (writeSearchObj.isLeft()) {
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if (parentNode.getOHHandle(leftchild) != null) throw new kelondroException(filename, "tried to create leftchild node twice. parent=" + new String(parentNode.getKey()) + ", leftchild=" + new String(new CacheNode(parentNode.getOHHandle(leftchild), (CacheNode) null, 0, true).getKey()));
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parentNode.setOHHandle(leftchild, theNode.handle());
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} else if (writeSearchObj.isRight()) {
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if (parentNode.getOHHandle(rightchild) != null) throw new kelondroException(filename, "tried to create rightchild node twice. parent=" + new String(parentNode.getKey()) + ", rightchild=" + new String(new CacheNode(parentNode.getOHHandle(rightchild), (CacheNode) null, 0, true).getKey()));
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parentNode.setOHHandle(rightchild, theNode.handle());
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} else {
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throw new kelondroException(filename, "neither left nor right child");
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}
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commitNode(parentNode);
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// now update recursively the node balance of the parentNode
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// what do we have:
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// - new Node, called 'theNode'
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// - parent Node
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// set balance factor in parent node(s)
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boolean increasedHight = true;
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String path = "";
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byte prevHight;
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RecordHandle parentSideHandle;
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while (increasedHight) {
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// update balance
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parentBalance = parentNode.getOHByte(balance); // {magic, balance}
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prevHight = parentBalance;
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parentSideHandle = parentNode.getOHHandle(leftchild);
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if ((parentSideHandle != null) && (parentSideHandle.equals(theNode.handle()))) {
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// is left child
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parentBalance++;
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path = "L" + path;
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}
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parentSideHandle =parentNode.getOHHandle(rightchild);
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if ((parentSideHandle != null) && (parentSideHandle.equals(theNode.handle()))) {
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// is right child
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parentBalance--;
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path = "R" + path;
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}
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increasedHight = ((java.lang.Math.abs(parentBalance) - java.lang.Math.abs(prevHight)) > 0);
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parentNode.setOHByte(balance, parentBalance);
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commitNode(parentNode);
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// here we either stop because we had no increased hight,
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// or we have a balance greater then 1 or less than -1 and we do rotation
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// or we crawl up the tree and change the next balance
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if (!(increasedHight)) break; // finished
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// check rotation need
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if (java.lang.Math.abs(parentBalance) > 1) {
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// rotate and stop then
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//System.out.println("* DB DEBUG: " + path.substring(0,2) + " ROTATION AT NODE " + parentNode.handle().toString() + ": BALANCE=" + parentOHByte[balance]);
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if (path.startsWith("LL")) {
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LL_RightRotation(parentNode, theNode);
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break;
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}
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if (path.startsWith("RR")) {
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RR_LeftRotation(parentNode, theNode);
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break;
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}
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if (path.startsWith("RL")) {
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final RecordHandle parentHandle = parentNode.handle();
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LL_RightRotation(theNode, new CacheNode(theNode.getOHHandle(leftchild), theNode, leftchild, false));
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parentNode = new CacheNode(parentHandle, null, 0, false); // reload the parent node
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RR_LeftRotation(parentNode, new CacheNode(parentNode.getOHHandle(rightchild), parentNode, rightchild, false));
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break;
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}
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if (path.startsWith("LR")) {
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final RecordHandle parentHandle = parentNode.handle();
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RR_LeftRotation(theNode, new CacheNode(theNode.getOHHandle(rightchild), theNode, rightchild, false));
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parentNode = new CacheNode(parentHandle, null, 0, false); // reload the parent node
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LL_RightRotation(parentNode, new CacheNode(parentNode.getOHHandle(leftchild), parentNode, leftchild, false));
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break;
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}
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break;
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}
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// crawl up the tree
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if (parentNode.getOHHandle(parent) == null) break; // root reached: stop
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theNode = parentNode;
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parentNode = new CacheNode(parentNode.getOHHandle(parent), null, 0, false);
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}
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|
|
result = null; // that means: no previous stored value present
|
|
}
|
|
}
|
|
//writeLock.release();
|
|
return result;
|
|
}
|
|
|
|
public synchronized void addUnique(final Row.Entry row) throws IOException {
|
|
this.put(row);
|
|
}
|
|
|
|
public synchronized void addUnique(final List<Row.Entry> rows) throws IOException {
|
|
final Iterator<Row.Entry> i = rows.iterator();
|
|
while (i.hasNext()) addUnique(i.next());
|
|
}
|
|
|
|
private void assignChild(final Node parentNode, final Node childNode, final int childType) throws IOException {
|
|
parentNode.setOHHandle(childType, childNode.handle());
|
|
childNode.setOHHandle(parent, parentNode.handle());
|
|
commitNode(parentNode);
|
|
commitNode(childNode);
|
|
}
|
|
|
|
private void replace(final Node oldNode, final Node oldNodeParent, final Node newNode) throws IOException {
|
|
// this routine looks where the oldNode is connected to, and replaces
|
|
// the anchor's link to the oldNode by the newNode-link
|
|
// the new link gets the anchor as parent link assigned
|
|
// the oldNode will not be updated, so this must be done outside this routine
|
|
// distinguish case where the oldNode is the root node
|
|
if (oldNodeParent == null) {
|
|
// this is the root, update root
|
|
setHandle(root, newNode.handle());
|
|
// update new Node
|
|
newNode.setOHHandle(parent, null);
|
|
commitNode(newNode);
|
|
} else {
|
|
// not the root, find parent
|
|
// ok, we have the parent, but for updating the child link we must know
|
|
// if the oldNode was left or right child
|
|
RecordHandle parentSideHandle = oldNodeParent.getOHHandle(leftchild);
|
|
if ((parentSideHandle != null) && (parentSideHandle.equals(oldNode.handle()))) {
|
|
// update left node from parent
|
|
oldNodeParent.setOHHandle(leftchild, newNode.handle());
|
|
}
|
|
parentSideHandle = oldNodeParent.getOHHandle(rightchild);
|
|
if ((parentSideHandle != null) && (parentSideHandle.equals(oldNode.handle()))) {
|
|
// update right node from parent
|
|
oldNodeParent.setOHHandle(rightchild, newNode.handle());
|
|
}
|
|
commitNode(oldNodeParent);
|
|
// update new Node
|
|
newNode.setOHHandle(parent, oldNodeParent.handle());
|
|
commitNode(newNode);
|
|
}
|
|
// finished. remember that we did not set the links to the oldNode
|
|
// we have also not set the children of the newNode.
|
|
// this must be done somewhere outside this function.
|
|
// if the oldNode is not needed any more, it can be disposed (check childs first).
|
|
}
|
|
|
|
private static byte max0(final byte b) {
|
|
if (b > 0) return b;
|
|
return 0;
|
|
}
|
|
|
|
private static byte min0(final byte b) {
|
|
if (b < 0) return b;
|
|
return 0;
|
|
}
|
|
|
|
private void LL_RightRotation(final Node parentNode, final CacheNode childNode) throws IOException {
|
|
// replace the parent node; the parent is afterwards unlinked
|
|
final RecordHandle p2Handle = parentNode.getOHHandle(parent);
|
|
final Node p2Node = (p2Handle == null) ? null : new CacheNode(p2Handle, null, 0, false);
|
|
replace(parentNode, p2Node, childNode);
|
|
|
|
// set the left son of the parent to the right son of the childNode
|
|
final RecordHandle childOfChild = childNode.getOHHandle(rightchild);
|
|
if (childOfChild == null) {
|
|
parentNode.setOHHandle(leftchild, null);
|
|
} else {
|
|
assignChild(parentNode, new CacheNode(childOfChild, childNode, rightchild, false), leftchild);
|
|
}
|
|
|
|
// link the old parent node as the right child of childNode
|
|
assignChild(childNode, parentNode, rightchild);
|
|
|
|
// - newBal(parent) = oldBal(parent) - 1 - max(oldBal(leftChild), 0)
|
|
// - newBal(leftChild) = oldBal(leftChild) - 1 + min(newBal(parent), 0)
|
|
byte parentBalance = parentNode.getOHByte(balance);
|
|
byte childBalance = childNode.getOHByte(balance);
|
|
final byte oldBalParent = parentBalance;
|
|
final byte oldBalChild = childBalance;
|
|
parentBalance = (byte) (oldBalParent - 1 - max0(oldBalChild));
|
|
childBalance = (byte) (oldBalChild - 1 + min0(parentBalance));
|
|
parentNode.setOHByte(balance, parentBalance);
|
|
childNode.setOHByte(balance, childBalance);
|
|
commitNode(parentNode);
|
|
commitNode(childNode);
|
|
}
|
|
|
|
private void RR_LeftRotation(final Node parentNode, final CacheNode childNode) throws IOException {
|
|
// replace the parent node; the parent is afterwards unlinked
|
|
final RecordHandle p2Handle = parentNode.getOHHandle(parent);
|
|
final Node p2Node = (p2Handle == null) ? null : new CacheNode(p2Handle, null, 0, false);
|
|
replace(parentNode, p2Node, childNode);
|
|
|
|
// set the left son of the parent to the right son of the childNode
|
|
final RecordHandle childOfChild = childNode.getOHHandle(leftchild);
|
|
if (childOfChild == null) {
|
|
parentNode.setOHHandle(rightchild, null);
|
|
} else {
|
|
assignChild(parentNode, new CacheNode(childOfChild, childNode, leftchild, false), rightchild);
|
|
}
|
|
|
|
// link the old parent node as the left child of childNode
|
|
assignChild(childNode, parentNode, leftchild);
|
|
|
|
// - newBal(parent) = oldBal(parent) + 1 - min(oldBal(rightChild), 0)
|
|
// - newBal(rightChild) = oldBal(rightChild) + 1 + max(newBal(parent), 0)
|
|
byte parentBalance = parentNode.getOHByte(balance);
|
|
byte childBalance = childNode.getOHByte(balance);
|
|
final byte oldBalParent = parentBalance;
|
|
final byte oldBalChild = childBalance;
|
|
parentBalance = (byte) (oldBalParent + 1 - min0(oldBalChild));
|
|
childBalance = (byte) (oldBalChild + 1 + max0(parentBalance));
|
|
parentNode.setOHByte(balance, parentBalance);
|
|
childNode.setOHByte(balance, childBalance);
|
|
commitNode(parentNode);
|
|
commitNode(childNode);
|
|
}
|
|
|
|
// Associates the specified value with the specified key in this map
|
|
public byte[] put(final byte[] key, final byte[] value) throws IOException {
|
|
final Row.Entry row = row().newEntry(new byte[][]{key, value});
|
|
final Row.Entry ret = replace(row);
|
|
if (ret == null) return null;
|
|
return ret.getColBytes(0);
|
|
}
|
|
|
|
// Removes the mapping for this key from this map if present (optional operation).
|
|
public Row.Entry remove(final byte[] key) throws IOException {
|
|
// the order inside the database file cannot be maintained, but iteration over objects will always maintain the object order
|
|
// therefore keepOrder should be true, because the effect is always given, while the data structure does not maintain order
|
|
// delete from database
|
|
synchronized(writeSearchObj) {
|
|
writeSearchObj.process(key);
|
|
if (writeSearchObj.found()) {
|
|
final CacheNode result = writeSearchObj.getMatcher();
|
|
final Row.Entry values = row().newEntry(result.getValueRow());
|
|
remove(result, writeSearchObj.getParent());
|
|
return values;
|
|
}
|
|
return null;
|
|
}
|
|
}
|
|
|
|
public Row.Entry removeOne() throws IOException {
|
|
// removes just any entry and removes that entry
|
|
synchronized(writeSearchObj) {
|
|
final CacheNode theOne = lastNode();
|
|
final Row.Entry values = row().newEntry(theOne.getValueRow());
|
|
remove(theOne, null);
|
|
return values;
|
|
}
|
|
}
|
|
|
|
public synchronized void removeAll() throws IOException {
|
|
while (size() > 0) remove(lastNode(), null);
|
|
}
|
|
|
|
private void remove(CacheNode node, final Node parentOfNode) throws IOException {
|
|
// there are three cases when removing a node
|
|
// - the node is a leaf - it can be removed easily
|
|
// - the node has one child - the child replaces the node
|
|
// - the node has two childs - it can be replaced either
|
|
// by the greatest node of the left child or the smallest
|
|
// node of the right child
|
|
|
|
Node childnode;
|
|
if ((node.getOHHandle(leftchild) == null) && (node.getOHHandle(rightchild) == null)) {
|
|
// easy case: the node is a leaf
|
|
if (parentOfNode == null) {
|
|
// this is the root!
|
|
setHandle(root, null);
|
|
} else {
|
|
RecordHandle h = parentOfNode.getOHHandle(leftchild);
|
|
if ((h != null) && (h.equals(node.handle()))) parentOfNode.setOHHandle(leftchild, null);
|
|
h = parentOfNode.getOHHandle(rightchild);
|
|
if ((h != null) && (h.equals(node.handle()))) parentOfNode.setOHHandle(rightchild, null);
|
|
commitNode(parentOfNode);
|
|
}
|
|
} else if ((node.getOHHandle(leftchild) != null) && (node.getOHHandle(rightchild) == null)) {
|
|
replace(node, parentOfNode, new CacheNode(node.getOHHandle(leftchild), node, leftchild, false));
|
|
} else if ((node.getOHHandle(leftchild) == null) && (node.getOHHandle(rightchild) != null)) {
|
|
replace(node, parentOfNode, new CacheNode(node.getOHHandle(rightchild), node, rightchild, false));
|
|
} else {
|
|
// difficult case: node has two children
|
|
final CacheNode repl = lastNode(new CacheNode(node.getOHHandle(leftchild), node, leftchild, false));
|
|
//System.out.println("last node is " + repl.toString());
|
|
// we remove that replacement node and put it where the node was
|
|
// this seems to be recursive, but is not since the replacement
|
|
// node cannot have two children (it would not have been the smallest or greatest)
|
|
Node n;
|
|
RecordHandle h;
|
|
// remove leaf
|
|
if ((repl.getOHHandle(leftchild) == null) && (repl.getOHHandle(rightchild) == null)) {
|
|
// the replacement cannot be the root, so simply remove from parent node
|
|
n = new CacheNode(repl.getOHHandle(parent), null, 0, false); // parent node of replacement node
|
|
h = n.getOHHandle(leftchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(leftchild, null);
|
|
h = n.getOHHandle(rightchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(rightchild, null);
|
|
commitNode(n);
|
|
} else if ((repl.getOHHandle(leftchild) != null) && (repl.getOHHandle(rightchild) == null)) {
|
|
try {
|
|
childnode = new CacheNode(repl.getOHHandle(leftchild), repl, leftchild, false);
|
|
replace(repl, new CacheNode(repl.getOHHandle(parent), null, 0, false), childnode);
|
|
} catch (final IllegalArgumentException e) {
|
|
// now treat the situation as if that link had been null before
|
|
n = new CacheNode(repl.getOHHandle(parent), null, 0, false); // parent node of replacement node
|
|
h = n.getOHHandle(leftchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(leftchild, null);
|
|
h = n.getOHHandle(rightchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(rightchild, null);
|
|
commitNode(n);
|
|
}
|
|
} else if ((repl.getOHHandle(leftchild) == null) && (repl.getOHHandle(rightchild) != null)) {
|
|
try {
|
|
childnode = new CacheNode(repl.getOHHandle(rightchild), repl, rightchild, false);
|
|
replace(repl, new CacheNode(repl.getOHHandle(parent), null, 0, false), childnode);
|
|
} catch (final IllegalArgumentException e) {
|
|
// now treat the situation as if that link had been null before
|
|
n = new CacheNode(repl.getOHHandle(parent), null, 0, false); // parent node of replacement node
|
|
h = n.getOHHandle(leftchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(leftchild, null);
|
|
h = n.getOHHandle(rightchild);
|
|
if ((h != null) && (h.equals(repl.handle()))) n.setOHHandle(rightchild, null);
|
|
commitNode(n);
|
|
}
|
|
}
|
|
//System.out.println("node before reload is " + node.toString());
|
|
node = new CacheNode(node.handle(), null, 0, false); // reload the node, it is possible that it has been changed
|
|
//System.out.println("node after reload is " + node.toString());
|
|
|
|
// now plant in the replha node
|
|
final byte b = node.getOHByte(balance); // save balance of disappearing node
|
|
final RecordHandle parentHandle = node.getOHHandle(parent);
|
|
final RecordHandle leftchildHandle = node.getOHHandle(leftchild);
|
|
final RecordHandle rightchildHandle = node.getOHHandle(rightchild);
|
|
replace(node, parentOfNode, repl);
|
|
repl.setOHByte(balance, b); // restore balance
|
|
repl.setOHHandle(parent, parentHandle); // restore handles
|
|
repl.setOHHandle(leftchild, leftchildHandle);
|
|
repl.setOHHandle(rightchild, rightchildHandle);
|
|
commitNode(repl);
|
|
// last thing to do: change uplinks of children to this new node
|
|
if (leftchildHandle != null) {
|
|
n = new CacheNode(leftchildHandle, node, leftchild, false);
|
|
n.setOHHandle(parent, repl.handle());
|
|
commitNode(n);
|
|
}
|
|
if (rightchildHandle != null) {
|
|
n = new CacheNode(rightchildHandle, node, rightchild, false);
|
|
n.setOHHandle(parent, repl.handle());
|
|
commitNode(n);
|
|
}
|
|
}
|
|
// move node to recycling queue
|
|
synchronized (this) {
|
|
deleteNode(node.handle());
|
|
}
|
|
}
|
|
|
|
protected CacheNode firstNode() throws IOException {
|
|
final RecordHandle h = getHandle(root);
|
|
if (h == null) return null;
|
|
return firstNode(new CacheNode(h, null, 0, true));
|
|
}
|
|
|
|
protected CacheNode firstNode(CacheNode node) throws IOException {
|
|
if (node == null) throw new IllegalArgumentException("firstNode: node=null");
|
|
RecordHandle h = node.getOHHandle(leftchild);
|
|
final HashSet<String> visitedNodeKeys = new HashSet<String>(); // to detect loops
|
|
String nodeKey;
|
|
while (h != null) {
|
|
try {
|
|
node = new CacheNode(h, node, leftchild, true);
|
|
nodeKey = new String(node.getKey());
|
|
if (visitedNodeKeys.contains(nodeKey)) throw new kelondroException(this.filename, "firstNode: database contains loops: '" + nodeKey + "' appears twice.");
|
|
visitedNodeKeys.add(nodeKey);
|
|
} catch (final IllegalArgumentException e) {
|
|
// return what we have
|
|
return node;
|
|
}
|
|
h = node.getOHHandle(leftchild);
|
|
}
|
|
return node;
|
|
}
|
|
|
|
protected CacheNode lastNode() throws IOException {
|
|
final RecordHandle h = getHandle(root);
|
|
if (h == null) return null;
|
|
return lastNode(new CacheNode(h, null, 0, true));
|
|
}
|
|
|
|
protected CacheNode lastNode(CacheNode node) throws IOException {
|
|
if (node == null) throw new IllegalArgumentException("lastNode: node=null");
|
|
RecordHandle h = node.getOHHandle(rightchild);
|
|
final HashSet<String> visitedNodeKeys = new HashSet<String>(); // to detect loops
|
|
String nodeKey;
|
|
while (h != null) {
|
|
try {
|
|
node = new CacheNode(h, node, rightchild, true);
|
|
nodeKey = new String(node.getKey());
|
|
if (visitedNodeKeys.contains(nodeKey)) throw new kelondroException(this.filename, "lastNode: database contains loops: '" + nodeKey + "' appears twice.");
|
|
visitedNodeKeys.add(nodeKey);
|
|
} catch (final IllegalArgumentException e) {
|
|
// return what we have
|
|
return node;
|
|
}
|
|
h = node.getOHHandle(rightchild);
|
|
}
|
|
return node;
|
|
}
|
|
|
|
private class nodeIterator implements Iterator<CacheNode> {
|
|
// we implement an iteration! (not a recursive function as the structure would suggest...)
|
|
// the iterator iterates Node objects
|
|
CacheNode nextNode = null;
|
|
boolean up, rot;
|
|
LinkedList<Object[]> nodeStack;
|
|
int count;
|
|
|
|
public nodeIterator(final boolean up, final boolean rotating) throws IOException {
|
|
this.count = 0;
|
|
this.up = up;
|
|
this.rot = rotating;
|
|
|
|
// initialize iterator
|
|
init((up) ? firstNode() : lastNode());
|
|
}
|
|
|
|
public nodeIterator(final boolean up, final boolean rotating, final byte[] firstKey, final boolean including) throws IOException {
|
|
this.count = 0;
|
|
this.up = up;
|
|
this.rot = rotating;
|
|
|
|
final Search search = new Search();
|
|
search.process(firstKey);
|
|
if (search.found()) {
|
|
init(search.getMatcher());
|
|
} else {
|
|
final CacheNode nn = search.getParent();
|
|
if (nn == null) {
|
|
this.nextNode = null;
|
|
} else {
|
|
// the node nn may be greater or smaller than the firstKey
|
|
// depending on the ordering direction,
|
|
// we must find the next smaller or greater node
|
|
// this is corrected in the initializer of nodeIterator
|
|
init(nn);
|
|
}
|
|
}
|
|
|
|
// correct nextNode upon start
|
|
// this happens, if the start node was not proper, or could not be found
|
|
while ((nextNode != null) && (nextNode.getKey() != null)) {
|
|
final int c = row().objectOrder.compare(firstKey, nextNode.getKey());
|
|
if (c == 0) {
|
|
if (including) {
|
|
break; // correct + finished
|
|
}
|
|
if (hasNext()) next(); else nextNode = null;
|
|
break; // corrected + finished
|
|
} else if (c < 0) {
|
|
if (up) {
|
|
break; // correct + finished
|
|
}
|
|
// firstKey < nextNode.getKey(): correct once
|
|
if (hasNext()) next(); else nextNode = null;
|
|
} else if (c > 0) {
|
|
if (up) {
|
|
// firstKey > nextNode.getKey(): correct once
|
|
if (hasNext()) next(); else nextNode = null;
|
|
} else {
|
|
break; // correct + finished
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
private void init(final CacheNode start) throws IOException {
|
|
this.nextNode = start;
|
|
|
|
// fill node stack for start node
|
|
nodeStack = new LinkedList<Object[]>();
|
|
|
|
RecordHandle searchHandle = getHandle(root);
|
|
if (searchHandle == null) {nextNode = null; return;}
|
|
|
|
CacheNode searchNode = new CacheNode(searchHandle, null, 0, false);
|
|
final byte[] startKey = start.getKey();
|
|
int c, ct;
|
|
while ((c = row().objectOrder.compare(startKey, searchNode.getKey())) != 0) {
|
|
// the current 'thisNode' is not the start node, put it on the stack
|
|
ct = (c < 0) ? leftchild : rightchild;
|
|
nodeStack.addLast(new Object[]{searchNode, Integer.valueOf(ct)});
|
|
|
|
// go to next node
|
|
searchHandle = searchNode.getOHHandle(ct);
|
|
if (searchHandle == null) throw new kelondroException(filename, "nodeIterator.init: start node does not exist (handle null)");
|
|
searchNode = new CacheNode(searchHandle, searchNode, ct, false);
|
|
if (searchNode == null) throw new kelondroException(filename, "nodeIterator.init: start node does not exist (node null)");
|
|
}
|
|
// now every parent node to the start node is on the stack
|
|
}
|
|
|
|
public boolean hasNext() {
|
|
return (rot && (size() > 0)) || (nextNode != null);
|
|
}
|
|
|
|
public CacheNode next() {
|
|
count++;
|
|
if ((rot) && (nextNode == null)) try {
|
|
init((up) ? firstNode() : lastNode());
|
|
} catch (final IOException e) {
|
|
throw new kelondroException(filename, "io-error while rot");
|
|
}
|
|
if (nextNode == null) throw new kelondroException(filename, "nodeIterator.next: no more entries available");
|
|
if ((count > size()) && (!(rot))) throw new kelondroException(filename, "nodeIterator.next: internal loopback; database corrupted");
|
|
final CacheNode ret = nextNode;
|
|
|
|
// middle-case
|
|
try {
|
|
int childtype = (up) ? rightchild : leftchild;
|
|
RecordHandle childHandle = nextNode.getOHHandle(childtype);
|
|
if (childHandle != null) {
|
|
//System.out.println("go to other leg, stack size=" + nodeStack.size());
|
|
// we have walked one leg of the tree; now go to the other one: step down to next child
|
|
final HashSet<RecordHandle> visitedNodeHandles = new HashSet<RecordHandle>(); // to detect loops
|
|
nodeStack.addLast(new Object[]{nextNode, Integer.valueOf(childtype)});
|
|
nextNode = new CacheNode(childHandle, nextNode, childtype, false);
|
|
childtype = (up) ? leftchild : rightchild;
|
|
while ((childHandle = nextNode.getOHHandle(childtype)) != null) {
|
|
if (visitedNodeHandles.contains(childHandle)) {
|
|
// try to repair the nextNode
|
|
nextNode.setOHHandle(childtype, null);
|
|
nextNode.commit();
|
|
logWarning("nodeIterator.next: internal loopback; fixed loop and try to go on");
|
|
break;
|
|
}
|
|
visitedNodeHandles.add(childHandle);
|
|
try {
|
|
nodeStack.addLast(new Object[]{nextNode, Integer.valueOf(childtype)});
|
|
nextNode = new CacheNode(childHandle, nextNode, childtype, false);
|
|
} catch (final IllegalArgumentException e) {
|
|
// return what we have
|
|
nodeStack.removeLast();
|
|
return ret;
|
|
}
|
|
}
|
|
// thats it: we are at a place where we can't go further
|
|
// nextNode is correct
|
|
} else {
|
|
//System.out.println("go up");
|
|
// we have walked along both legs of the child-trees.
|
|
|
|
// Now step up.
|
|
if (nodeStack.size() == 0) {
|
|
nextNode = null;
|
|
} else {
|
|
Object[] stacktop;
|
|
CacheNode parentNode = null;
|
|
int parentpointer = (up) ? rightchild : leftchild;
|
|
while ((nodeStack.size() != 0) && (parentpointer == ((up) ? rightchild : leftchild))) {
|
|
//System.out.println("step up");
|
|
// go on, walk up further
|
|
stacktop = nodeStack.removeLast(); // top of stack: Node/parentpointer pair
|
|
parentNode = (CacheNode) stacktop[0];
|
|
parentpointer = ((Integer) stacktop[1]).intValue();
|
|
}
|
|
if ((nodeStack.size() == 0) && (parentpointer == ((up) ? rightchild : leftchild))) {
|
|
nextNode = null;
|
|
} else {
|
|
nextNode = parentNode;
|
|
}
|
|
}
|
|
}
|
|
} catch (final IOException e) {
|
|
nextNode = null;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
public void remove() {
|
|
throw new java.lang.UnsupportedOperationException("kelondroTree: remove in kelondro node iterator not yet supported");
|
|
}
|
|
}
|
|
|
|
public TreeMap<String, Row.Entry> rowMap(final boolean up, final byte[] firstKey, final boolean including, final int count) throws IOException {
|
|
// returns an ordered map of keys/row relations; key objects are of type String, value objects are of type byte[][]
|
|
final ByteOrder setOrder = (ByteOrder) row().objectOrder.clone();
|
|
setOrder.direction(up);
|
|
setOrder.rotate(firstKey);
|
|
final TreeMap<String, Row.Entry> rows = new TreeMap<String, Row.Entry>(this.loopDetectionOrder);
|
|
CacheNode n;
|
|
String key;
|
|
synchronized (this) {
|
|
final Iterator<CacheNode> i = (firstKey == null) ? new nodeIterator(up, false) : new nodeIterator(up, false, firstKey, including);
|
|
while ((rows.size() < count) && (i.hasNext())) {
|
|
n = i.next();
|
|
if (n == null) return rows;
|
|
key = new String(n.getKey());
|
|
if (rows.put(key, row().newEntry(n.getValueRow())) != null) return rows; // protection against loops
|
|
}
|
|
}
|
|
return rows;
|
|
}
|
|
|
|
public TreeSet<String> keySet(final boolean up, final boolean rotating, final byte[] firstKey, final boolean including, final int count) throws IOException {
|
|
// returns an ordered set of keys; objects are of type String
|
|
final ByteOrder setOrder = (ByteOrder) row().objectOrder.clone();
|
|
setOrder.direction(up);
|
|
setOrder.rotate(firstKey);
|
|
final TreeSet<String> set = new TreeSet<String>(this.loopDetectionOrder);
|
|
Node n;
|
|
synchronized (this) {
|
|
final Iterator<CacheNode> i = (firstKey == null) ? new nodeIterator(up, rotating) : new nodeIterator(up, rotating, firstKey, including);
|
|
while ((set.size() < count) && (i.hasNext())) {
|
|
n = i.next();
|
|
if ((n != null) && (n.getKey() != null)) set.add(new String(n.getKey()));
|
|
}
|
|
}
|
|
return set;
|
|
}
|
|
|
|
public CloneableIterator<Row.Entry> rows(final boolean up, final byte[] firstKey) throws IOException {
|
|
// iterates the rows of the Nodes
|
|
// enumerated objects are of type byte[][]
|
|
// iterates the elements in a sorted way.
|
|
// if iteration should start at smallest element, set firstKey to null
|
|
return new rowIterator(up, firstKey, this.size());
|
|
}
|
|
|
|
public CloneableIterator<Row.Entry> rows() throws IOException {
|
|
return new rowIterator(true, null, this.size());
|
|
}
|
|
|
|
public class rowIterator implements CloneableIterator<Row.Entry> {
|
|
|
|
int chunkSize;
|
|
boolean inc;
|
|
long count;
|
|
byte[] lastKey;
|
|
TreeMap<String, Row.Entry> rowBuffer;
|
|
Iterator<Map.Entry<String, Row.Entry>> bufferIterator;
|
|
long guessedCountLimit;
|
|
|
|
public rowIterator(final boolean up, final byte[] firstKey, final long guessedCountLimit) throws IOException {
|
|
this.guessedCountLimit = guessedCountLimit;
|
|
inc = up;
|
|
count = 0;
|
|
lastKey = null;
|
|
//System.out.println("*** rowIterator: " + filename + ": readAheadChunkSize = " + readAheadChunkSize + ", lastIteratorCount = " + lastIteratorCount);
|
|
readAheadChunkSize = Math.min(1000, 3 + (int) ((3 * readAheadChunkSize + lastIteratorCount) / 4));
|
|
chunkSize = (int) Math.min(readAheadChunkSize / 3, guessedCountLimit);
|
|
rowBuffer = rowMap(inc, firstKey, true, chunkSize);
|
|
bufferIterator = rowBuffer.entrySet().iterator();
|
|
lastIteratorCount = 0;
|
|
}
|
|
|
|
public rowIterator clone(final Object secondStart) {
|
|
try {
|
|
return new rowIterator(inc, (byte[]) secondStart, guessedCountLimit);
|
|
} catch (final IOException e) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
public boolean hasNext() {
|
|
return ((bufferIterator != null) && (bufferIterator.hasNext()) && (count < size()));
|
|
}
|
|
|
|
public Row.Entry next() {
|
|
if (!(bufferIterator.hasNext())) return null;
|
|
final Map.Entry<String, Row.Entry> entry = bufferIterator.next();
|
|
lastKey = entry.getKey().getBytes();
|
|
|
|
// check if this was the last entry in the rowBuffer
|
|
if (!(bufferIterator.hasNext())) {
|
|
// assign next buffer chunk
|
|
try {
|
|
lastKey[lastKey.length - 1]++; // ***BUG??? FIXME
|
|
rowBuffer = rowMap(inc, lastKey, false, chunkSize);
|
|
bufferIterator = rowBuffer.entrySet().iterator();
|
|
} catch (final IOException e) {
|
|
rowBuffer = null;
|
|
bufferIterator = null;
|
|
}
|
|
}
|
|
|
|
// return the row
|
|
count++;
|
|
lastIteratorCount++;
|
|
return entry.getValue();
|
|
}
|
|
|
|
public void remove() {
|
|
if (lastKey != null) try {
|
|
Tree.this.remove(lastKey);
|
|
} catch (final IOException e) {
|
|
// do nothing
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
public CloneableIterator<byte[]> keys(final boolean up, final byte[] firstKey) throws IOException {
|
|
return new keyIterator(up, firstKey, this.size());
|
|
}
|
|
|
|
public class keyIterator implements CloneableIterator<byte[]> {
|
|
|
|
int chunkSize;
|
|
boolean inc;
|
|
long count;
|
|
byte[] lastKey;
|
|
TreeSet<String> keyBuffer;
|
|
Iterator<String> bufferIterator;
|
|
long guessedCountLimit;
|
|
|
|
public keyIterator(final boolean up, final byte[] firstKey, final long guessedCountLimit) throws IOException {
|
|
this.guessedCountLimit = guessedCountLimit;
|
|
inc = up;
|
|
count = 0;
|
|
lastKey = null;
|
|
//System.out.println("*** rowIterator: " + filename + ": readAheadChunkSize = " + readAheadChunkSize + ", lastIteratorCount = " + lastIteratorCount);
|
|
readAheadChunkSize = Math.min(1000, 3 + (int) ((3 * readAheadChunkSize + lastIteratorCount) / 4));
|
|
chunkSize = (int) Math.min(readAheadChunkSize / 3, guessedCountLimit);
|
|
keyBuffer = keySet(inc, false, firstKey, true, chunkSize);
|
|
bufferIterator = keyBuffer.iterator();
|
|
lastIteratorCount = 0;
|
|
}
|
|
|
|
public keyIterator clone(final Object secondStart) {
|
|
try {
|
|
return new keyIterator(inc, (byte[]) secondStart, guessedCountLimit);
|
|
} catch (final IOException e) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
public boolean hasNext() {
|
|
return ((bufferIterator != null) && (bufferIterator.hasNext()) && (count < size()));
|
|
}
|
|
|
|
public byte[] next() {
|
|
if (!(bufferIterator.hasNext())) return null;
|
|
lastKey = bufferIterator.next().getBytes();
|
|
|
|
// check if this was the last entry in the rowBuffer
|
|
if (!(bufferIterator.hasNext())) {
|
|
// assign next buffer chunk
|
|
try {
|
|
lastKey[lastKey.length - 1]++; // ***BUG??? FIXME
|
|
keyBuffer = keySet(inc, false, lastKey, false, chunkSize);
|
|
bufferIterator = keyBuffer.iterator();
|
|
} catch (final IOException e) {
|
|
keyBuffer = null;
|
|
bufferIterator = null;
|
|
}
|
|
}
|
|
|
|
// return the row
|
|
count++;
|
|
lastIteratorCount++;
|
|
return lastKey;
|
|
}
|
|
|
|
public void remove() {
|
|
if (lastKey != null) try {
|
|
Tree.this.remove(lastKey);
|
|
} catch (final IOException e) {
|
|
// do nothing
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
public int imp(final File file, final String separator) throws IOException {
|
|
// imports a value-separated file, returns number of records that have been read
|
|
|
|
final RandomAccessFile f = new RandomAccessFile(file,"r");
|
|
String s;
|
|
StringTokenizer st;
|
|
int recs = 0;
|
|
final Row.Entry buffer = row().newEntry();
|
|
int c;
|
|
int line = 0;
|
|
while ((s = f.readLine()) != null) {
|
|
s = s.trim();
|
|
line++;
|
|
if ((s.length() > 0) && (!(s.startsWith("#")))) {
|
|
st = new StringTokenizer(s, separator);
|
|
// buffer the entry
|
|
c = 0;
|
|
while ((c < row().columns()) && (st.hasMoreTokens())) {
|
|
buffer.setCol(c++, st.nextToken().trim().getBytes());
|
|
}
|
|
if ((st.hasMoreTokens()) || (c != row().columns())) {
|
|
System.err.println("inapropriate number of entries in line " + line);
|
|
} else {
|
|
put(buffer);
|
|
recs++;
|
|
}
|
|
|
|
}
|
|
}
|
|
return recs;
|
|
}
|
|
|
|
public synchronized int height() {
|
|
try {
|
|
final RecordHandle h = getHandle(root);
|
|
if (h == null) return 0;
|
|
return height(new CacheNode(h, null, 0, false));
|
|
} catch (final IOException e) {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
private int height(final CacheNode node) throws IOException {
|
|
if (node == null) return 0;
|
|
RecordHandle h = node.getOHHandle(leftchild);
|
|
final int hl = (h == null) ? 0 : height(new CacheNode(h, node, leftchild, false));
|
|
h = node.getOHHandle(rightchild);
|
|
final int hr = (h == null) ? 0 : height(new CacheNode(h, node, rightchild, false));
|
|
if (hl > hr) return hl + 1;
|
|
return hr + 1;
|
|
}
|
|
|
|
public void print() throws IOException {
|
|
super.print();
|
|
final int height = height();
|
|
System.out.println("HEIGHT = " + height);
|
|
Vector<RecordHandle> thisline = new Vector<RecordHandle>();
|
|
thisline.add(getHandle(root));
|
|
Vector<RecordHandle> nextline;
|
|
RecordHandle handle;
|
|
Node node;
|
|
int linelength;
|
|
final int width = (1 << (height - 1)) * (row().width(0) + 1);
|
|
String key;
|
|
for (int h = 1; h < height; h++) {
|
|
linelength = width / (thisline.size() * 2);
|
|
nextline = new Vector<RecordHandle>();
|
|
for (int i = 0; i < thisline.size(); i++) {
|
|
handle = thisline.elementAt(i);
|
|
if (handle == null) {
|
|
node = null;
|
|
key = "[..]";
|
|
} else {
|
|
node = new CacheNode(handle, null, 0, false);
|
|
if (node == null) key = "NULL"; else key = new String(node.getKey());
|
|
}
|
|
System.out.print(key);
|
|
for (int j = 0; j < (linelength - key.length()); j++) System.out.print("-");
|
|
System.out.print("+");
|
|
for (int j = 0; j < (linelength - 1); j++) System.out.print(" ");
|
|
if (node == null) {
|
|
nextline.add(null);
|
|
nextline.add(null);
|
|
} else {
|
|
nextline.add(node.getOHHandle(leftchild));
|
|
nextline.add(node.getOHHandle(rightchild));
|
|
}
|
|
}
|
|
System.out.println();
|
|
for (int i = 0; i < thisline.size(); i++) {
|
|
System.out.print("|");
|
|
for (int j = 0; j < (linelength - 1); j++) System.out.print(" ");
|
|
System.out.print("|");
|
|
for (int j = 0; j < (linelength - 1); j++) System.out.print(" ");
|
|
}
|
|
System.out.println();
|
|
thisline = nextline;
|
|
nextline = null;
|
|
}
|
|
// now print last line
|
|
if ((thisline != null) && (width >= 0)) {
|
|
linelength = width / thisline.size();
|
|
for (int i = 0; i < thisline.size(); i++) {
|
|
handle = thisline.elementAt(i);
|
|
if (handle == null) {
|
|
node = null;
|
|
key = "NULL";
|
|
} else {
|
|
node = new CacheNode(handle, null, 0, false);
|
|
if (node == null) key = "NULL"; else key = new String(node.getKey());
|
|
}
|
|
System.out.print(key);
|
|
for (int j = 0; j < (linelength - key.length()); j++) System.out.print(" ");
|
|
}
|
|
}
|
|
System.out.println();
|
|
}
|
|
|
|
public static void cmd(final String[] args) {
|
|
System.out.print("kelondroTree ");
|
|
for (int i = 0; i < args.length; i++) System.out.print(args[i] + " ");
|
|
System.out.println("");
|
|
byte[] ret = null;
|
|
try {
|
|
if ((args.length > 4) || (args.length < 1)) {
|
|
System.err.println("usage: kelondroTree -c|-u|-v|-g|-d|-i|-s [file]|[key [value]] <db-file>");
|
|
System.err.println("( create, update, view, get, delete, imp, shell)");
|
|
System.exit(0);
|
|
} else if (args.length == 1) {
|
|
if (args[0].equals("-t")) {
|
|
// test script
|
|
final File testFile = new File("test.db");
|
|
while (testFile.exists()) testFile.delete();
|
|
final Tree fm = new Tree(testFile, true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
final byte[] dummy = "".getBytes();
|
|
fm.put("abc0".getBytes(), dummy); fm.put("bcd0".getBytes(), dummy);
|
|
fm.put("def0".getBytes(), dummy); fm.put("bab0".getBytes(), dummy);
|
|
fm.put("abc1".getBytes(), dummy); fm.put("bcd1".getBytes(), dummy);
|
|
fm.put("def1".getBytes(), dummy); fm.put("bab1".getBytes(), dummy);
|
|
fm.put("abc2".getBytes(), dummy); fm.put("bcd2".getBytes(), dummy);
|
|
fm.put("def2".getBytes(), dummy); fm.put("bab2".getBytes(), dummy);
|
|
fm.put("abc3".getBytes(), dummy); fm.put("bcd3".getBytes(), dummy);
|
|
fm.put("def3".getBytes(), dummy); fm.put("bab3".getBytes(), dummy);
|
|
fm.print();
|
|
fm.remove("def1".getBytes()); fm.remove("bab1".getBytes());
|
|
fm.remove("abc2".getBytes()); fm.remove("bcd2".getBytes());
|
|
fm.remove("def2".getBytes()); fm.remove("bab2".getBytes());
|
|
fm.put("def1".getBytes(), dummy); fm.put("bab1".getBytes(), dummy);
|
|
fm.put("abc2".getBytes(), dummy); fm.put("bcd2".getBytes(), dummy);
|
|
fm.put("def2".getBytes(), dummy); fm.put("bab2".getBytes(), dummy);
|
|
fm.print();
|
|
fm.close();
|
|
ret = null;
|
|
}
|
|
} else if (args.length == 2) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
if (args[0].equals("-v")) {
|
|
fm.print();
|
|
ret = null;
|
|
}
|
|
fm.close();
|
|
} else if (args.length == 3) {
|
|
if (args[0].equals("-d")) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
fm.remove(args[2].getBytes());
|
|
fm.close();
|
|
} else if (args[0].equals("-i")) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
final int i = fm.imp(new File(args[1]),";");
|
|
fm.close();
|
|
ret = (i + " records imported").getBytes();
|
|
} else if (args[0].equals("-s")) {
|
|
final String db = args[2];
|
|
BufferedReader f = null;
|
|
try {
|
|
f = new BufferedReader(new FileReader(args[1]));
|
|
String m;
|
|
while (true) {
|
|
m = f.readLine();
|
|
if (m == null) break;
|
|
if ((m.length() > 1) && (!m.startsWith("#"))) {
|
|
m = m + " " + db;
|
|
cmd(line2args(m));
|
|
}
|
|
}
|
|
ret = null;
|
|
} finally {
|
|
if (f != null) try {f.close();}catch(final Exception e){}
|
|
}
|
|
} else if (args[0].equals("-g")) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
final Row.Entry ret2 = fm.get(args[2].getBytes());
|
|
ret = ((ret2 == null) ? null : ret2.getColBytes(1));
|
|
fm.close();
|
|
} else if (args[0].equals("-n")) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
//byte[][] keys = fm.getSequentialKeys(args[2].getBytes(), 500, true);
|
|
final Iterator<Row.Entry> rowIt = fm.rows(true, (args[2].length() == 0) ? null : args[2].getBytes());
|
|
final Vector<String> v = new Vector<String>();
|
|
while (rowIt.hasNext()) v.add(rowIt.next().getColString(0, null));
|
|
ret = v.toString().getBytes();
|
|
fm.close();
|
|
}
|
|
} else if (args.length == 4) {
|
|
if (args[0].equals("-c")) {
|
|
// create <keylen> <valuelen> <filename>
|
|
final File f = new File(args[3]);
|
|
if (f.exists()) f.delete();
|
|
final Row lens = new Row("byte[] key-" + Integer.parseInt(args[1]) + ", byte[] value-" + Integer.parseInt(args[2]), NaturalOrder.naturalOrder);
|
|
final Tree fm = new Tree(f, true, 10, lens);
|
|
fm.close();
|
|
} else if (args[0].equals("-u")) {
|
|
final Tree fm = new Tree(new File(args[1]), true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
ret = fm.put(args[1].getBytes(), args[2].getBytes());
|
|
fm.close();
|
|
}
|
|
}
|
|
if (ret == null)
|
|
System.out.println("NULL");
|
|
else
|
|
System.out.println(new String(ret));
|
|
} catch (final Exception e) {
|
|
e.printStackTrace();
|
|
}
|
|
}
|
|
|
|
public static void main(final String[] args) {
|
|
//cmd(args);
|
|
//iterationtest();
|
|
bigtest(Integer.parseInt(args[0]));
|
|
//randomtest(Integer.parseInt(args[0]));
|
|
//smalltest();
|
|
}
|
|
|
|
public static String[] permutations(final int letters) {
|
|
String p = "";
|
|
for (int i = 0; i < letters; i++) p = p + ((char) (('A') + i));
|
|
return permutations(p);
|
|
}
|
|
public static String[] permutations(final String source) {
|
|
if (source.length() == 0) return new String[0];
|
|
if (source.length() == 1) return new String[]{source};
|
|
final char c = source.charAt(0);
|
|
final String[] recres = permutations(source.substring(1));
|
|
final String[] result = new String[source.length() * recres.length];
|
|
for (int perm = 0; perm < recres.length; perm++) {
|
|
result[perm * source.length()] = c + recres[perm];
|
|
for (int pos = 1; pos < source.length() - 1; pos++) {
|
|
result[perm * source.length() + pos] = recres[perm].substring(0, pos) + c + recres[perm].substring(pos);
|
|
}
|
|
result[perm * source.length() + source.length() - 1] = recres[perm] + c;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
public static byte[] testWord(final char c) {
|
|
return new byte[]{(byte) c, 32, 32, 32};
|
|
}
|
|
|
|
public static void randomtest(final int elements) {
|
|
System.out.println("random " + elements + ":");
|
|
final String s = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".substring(0, elements);
|
|
String t, d;
|
|
char c;
|
|
Tree tt = null;
|
|
final File testFile = new File("test.db");
|
|
byte[] b;
|
|
try {
|
|
int steps = 0;
|
|
while (true) {
|
|
if (testFile.exists()) testFile.delete();
|
|
tt = new Tree(testFile, true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
steps = 10 + ((int) System.currentTimeMillis() % 7) * (((int) System.currentTimeMillis() + 17) % 11);
|
|
t = s;
|
|
d = "";
|
|
System.out.println("NEW SESSION");
|
|
for (int i = 0; i < steps; i++) {
|
|
if ((d.length() < 3) || ((t.length() > 0) && (((int) System.currentTimeMillis() % 7) < 2))) {
|
|
// add one
|
|
c = t.charAt((int) (System.currentTimeMillis() % t.length()));
|
|
b = testWord(c);
|
|
tt.put(b, b);
|
|
d = d + c;
|
|
t = t.substring(0, t.indexOf(c)) + t.substring(t.indexOf(c) + 1);
|
|
System.out.println("added " + new String(b));
|
|
} else {
|
|
// delete one
|
|
c = d.charAt((int) (System.currentTimeMillis() % d.length()));
|
|
b = testWord(c);
|
|
tt.remove(b);
|
|
d = d.substring(0, d.indexOf(c)) + d.substring(d.indexOf(c) + 1);
|
|
t = t + c;
|
|
System.out.println("removed " + new String(b));
|
|
}
|
|
//tt.printCache();
|
|
//tt.print();
|
|
|
|
if (countElements(tt) != tt.size()) {
|
|
System.out.println("wrong size for this table:");
|
|
tt.print();
|
|
}
|
|
|
|
// check all words within
|
|
for (int j = 0; j < d.length(); j++) {
|
|
if (tt.get(testWord(d.charAt(j))) == null) {
|
|
System.out.println("missing entry " + d.charAt(j) + " in this table:");
|
|
tt.print();
|
|
}
|
|
}
|
|
// check all words outside
|
|
for (int j = 0; j < t.length(); j++) {
|
|
if (tt.get(testWord(t.charAt(j))) != null) {
|
|
System.out.println("superfluous entry " + t.charAt(j) + " in this table:");
|
|
tt.print();
|
|
}
|
|
}
|
|
if (tt.get(testWord('z')) != null) {
|
|
System.out.println("superfluous entry z in this table:");
|
|
tt.print();
|
|
}
|
|
|
|
}
|
|
//tt.print();
|
|
tt.close();
|
|
}
|
|
|
|
} catch (final Exception e) {
|
|
e.printStackTrace();
|
|
if (tt != null) try {tt.print();} catch (final IOException ee) {}
|
|
System.out.println("TERMINATED");
|
|
}
|
|
}
|
|
|
|
public static void smalltest() {
|
|
final File f = new File("test.db");
|
|
if (f.exists()) f.delete();
|
|
try {
|
|
final Tree tt = new Tree(f, true, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
byte[] b;
|
|
b = testWord('B'); tt.put(b, b); //tt.print();
|
|
b = testWord('C'); tt.put(b, b); //tt.print();
|
|
b = testWord('D'); tt.put(b, b); //tt.print();
|
|
b = testWord('A'); tt.put(b, b); //tt.print();
|
|
b = testWord('D'); tt.remove(b); //tt.print();
|
|
b = testWord('B'); tt.remove(b); //tt.print();
|
|
b = testWord('B'); tt.put(b, b); //tt.print();
|
|
b = testWord('D'); tt.put(b, b);
|
|
b = testWord('E'); tt.put(b, b);
|
|
b = testWord('F'); tt.put(b, b);
|
|
b = testWord('G'); tt.put(b, b);
|
|
b = testWord('H'); tt.put(b, b);
|
|
b = testWord('I'); tt.put(b, b);
|
|
b = testWord('J'); tt.put(b, b);
|
|
b = testWord('K'); tt.put(b, b);
|
|
b = testWord('L'); tt.put(b, b);
|
|
final int c = countElements(tt);
|
|
System.out.println("elements: " + c);
|
|
final Iterator<Row.Entry> i = tt.rows(true, testWord('G'));
|
|
for (int j = 0; j < c; j++) {
|
|
System.out.println("Row " + j + ": " + new String((i.next()).getColBytes(0)));
|
|
}
|
|
System.out.println("TERMINATED");
|
|
} catch (final IOException e) {
|
|
e.printStackTrace();
|
|
}
|
|
}
|
|
|
|
/*
|
|
public static void iterationtest() {
|
|
File f = new File("test.db");
|
|
if (f.exists()) f.delete();
|
|
try {
|
|
kelondroTree tt = new kelondroTree(f, 0, 0, 10, 4, 4, true);
|
|
byte[] b;
|
|
for (int i = 0; i < 100; i++) {
|
|
b = ("T" + i).getBytes(); tt.put(b, b);
|
|
}
|
|
Iterator i = tt.keys(true, false, null);
|
|
while (i.hasNext()) System.out.print((String) i.next() + ", ");
|
|
System.out.println();
|
|
|
|
i = tt.keys(true, false, "T80".getBytes());
|
|
while (i.hasNext()) System.out.print((String) i.next() + ", ");
|
|
System.out.println();
|
|
|
|
i = tt.keys(true, true, "T80".getBytes());
|
|
for (int j = 0; j < 40; j++) System.out.print((String) i.next() + ", ");
|
|
System.out.println();
|
|
|
|
i = tt.keys(false, true, "T20".getBytes());
|
|
for (int j = 0; j < 40; j++) System.out.print((String) i.next() + ", ");
|
|
System.out.println();
|
|
|
|
tt.close();
|
|
} catch (IOException e) {
|
|
e.printStackTrace();
|
|
}
|
|
}
|
|
*/
|
|
|
|
public static Tree testTree(final File f, final String testentities) throws IOException {
|
|
if (f.exists()) f.delete();
|
|
final Tree tt = new Tree(f, false, 10, new Row("byte[] a-4, byte[] b-4", NaturalOrder.naturalOrder));
|
|
byte[] b;
|
|
for (int i = 0; i < testentities.length(); i++) {
|
|
b = testWord(testentities.charAt(i));
|
|
tt.put(b, b);
|
|
}
|
|
return tt;
|
|
}
|
|
|
|
public static void bigtest(final int elements) {
|
|
System.out.println("starting big test with " + elements + " elements:");
|
|
final long start = System.currentTimeMillis();
|
|
final String[] s = permutations(elements);
|
|
Tree tt;
|
|
final File testFile = new File("test.db");
|
|
try {
|
|
for (int i = 0; i < s.length; i++) {
|
|
System.out.println("*** probing tree " + i + " for permutation " + s[i]);
|
|
// generate tree and delete elements
|
|
tt = testTree(testFile, s[i]);
|
|
//tt.print();
|
|
if (countElements(tt) != tt.size()) {
|
|
System.out.println("wrong size for " + s[i]);
|
|
tt.print();
|
|
}
|
|
tt.close();
|
|
for (int j = 0; j < s.length; j++) {
|
|
tt = testTree(testFile, s[i]);
|
|
//tt.print();
|
|
// delete by permutation j
|
|
for (int elt = 0; elt < s[j].length(); elt++) {
|
|
tt.remove(testWord(s[j].charAt(elt)));
|
|
//tt.print();
|
|
if (countElements(tt) != tt.size()) {
|
|
System.out.println("ERROR! wrong size for probe tree " + s[i] + "; probe delete " + s[j] + "; position " + elt);
|
|
tt.print();
|
|
}
|
|
}
|
|
// add another one
|
|
//tt.print();
|
|
/*
|
|
b = testWord('0'); tt.put(b, b);
|
|
b = testWord('z'); tt.put(b, b);
|
|
b = testWord('G'); tt.put(b, b);
|
|
b = testWord('t'); tt.put(b, b);
|
|
if (countElements(tt) != tt.size()) {
|
|
System.out.println("ERROR! wrong size for probe tree " + s[i] + "; probe delete " + s[j] + "; final add");
|
|
tt.print();
|
|
}
|
|
tt.print();
|
|
*/
|
|
// close this
|
|
tt.close();
|
|
}
|
|
}
|
|
System.out.println("FINISHED test after " + ((System.currentTimeMillis() - start) / 1000) + " seconds.");
|
|
} catch (final Exception e) {
|
|
e.printStackTrace();
|
|
System.out.println("TERMINATED");
|
|
}
|
|
}
|
|
|
|
public static int countElements(final ObjectIndex t) {
|
|
int count = 0;
|
|
try {
|
|
final Iterator<Row.Entry> iter = t.rows();
|
|
Row.Entry row;
|
|
while (iter.hasNext()) {
|
|
count++;
|
|
row = iter.next();
|
|
if (row == null) System.out.println("ERROR! null element found");
|
|
// else System.out.println("counted element: " + new
|
|
// String(n.getKey()));
|
|
}
|
|
} catch (final IOException e) {
|
|
}
|
|
return count;
|
|
}
|
|
|
|
}
|