yacy_search_server/source/net/yacy/kelondro/blob/Tables.java
2012-06-08 09:30:51 +02:00

572 lines
20 KiB
Java

// Tables.java
// (C) 2010 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 14.01.2010 on http://yacy.net
//
// This is a part of YaCy, a peer-to-peer based web search engine
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// LICENSE
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package net.yacy.kelondro.blob;
import java.io.File;
import java.io.IOException;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.TreeMap;
import java.util.concurrent.ConcurrentHashMap;
import java.util.regex.Pattern;
import net.yacy.cora.date.GenericFormatter;
import net.yacy.cora.document.UTF8;
import net.yacy.kelondro.index.RowSpaceExceededException;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.util.ByteArray;
import net.yacy.kelondro.util.ByteBuffer;
import net.yacy.kelondro.util.FileUtils;
import net.yacy.kelondro.util.LookAheadIterator;
public class Tables implements Iterable<String> {
private static final String suffix = ".bheap";
private static final String system_table_pkcounter = "pkcounter";
private static final String system_table_pkcounter_counterName = "pk";
private final File location;
private final ConcurrentHashMap<String, BEncodedHeap> tables;
int keymaxlen;
// use our own formatter to prevent concurrency locks with other processes
private final static GenericFormatter my_SHORT_MILSEC_FORMATTER = new GenericFormatter(GenericFormatter.FORMAT_SHORT_MILSEC, 1);
public Tables(final File location, final int keymaxlen) {
this.location = new File(location.getAbsolutePath());
if (!this.location.exists()) this.location.mkdirs();
this.keymaxlen = keymaxlen;
this.tables = new ConcurrentHashMap<String, BEncodedHeap>();
final String[] files = this.location.list();
File file;
// lazy initialization: do not open the database files here
for (final String f: files) {
if (f.endsWith(suffix)) {
file = new File(this.location, f);
if (file.length() == 0) {
file.delete();
continue;
}
}
}
}
@Override
public Iterator<String> iterator() {
// we did a lazy initialization, but here we must discover all actually existing tables
String tablename;
File file;
final String[] files = this.location.list();
for (final String f: files) {
if (f.endsWith(suffix)) {
file = new File(this.location, f);
if (file.length() == 0) {
continue;
}
tablename = f.substring(0, f.length() - suffix.length());
try {
getHeap(tablename);
} catch (final IOException e) {
}
}
}
// now the list of tables is enriched, return an iterator
return this.tables.keySet().iterator();
}
public void close(final String tablename) {
final BEncodedHeap heap = this.tables.remove(tablename);
if (heap == null) return;
heap.close();
}
public synchronized void close() {
for (final BEncodedHeap heap: this.tables.values()) heap.close();
this.tables.clear();
}
public void clear(final String tablename) {
try {
BEncodedHeap heap = getHeap(tablename);
if (heap != null) {
final File f = heap.getFile();
heap.clear();
heap.close();
FileUtils.deletedelete(f);
heap = null;
}
} catch (final IOException e) {
Log.logException(e);
} finally {
this.tables.remove(tablename);
}
}
public boolean hasHeap(final String tablename) {
try {
return getHeap(tablename) != null;
} catch (final IOException e) {
return false;
}
}
public BEncodedHeap getHeap(final String tablename) throws IOException {
final String table = tablename + suffix;
BEncodedHeap heap = this.tables.get(tablename);
if (heap != null) return heap;
// open a new heap and register it in the tables
final File heapf = new File(this.location, table);
heap = new BEncodedHeap(heapf, this.keymaxlen);
this.tables.put(tablename, heap);
return heap;
}
/**
* get the total number of known tables
* @return
*/
public int size() {
return this.tables.size();
}
public int size(final String table) throws IOException {
final BEncodedHeap heap = getHeap(table);
return heap.size();
}
private byte[] ukey(final String tablename) throws IOException, RowSpaceExceededException {
Row row = select(system_table_pkcounter, UTF8.getBytes(tablename));
if (row == null) {
// table counter entry in pkcounter table does not exist: make a new table entry
row = new Row(UTF8.getBytes(tablename), system_table_pkcounter_counterName, UTF8.getBytes(int2key(0)));
update(system_table_pkcounter, row);
}
byte[] pk = row.get(system_table_pkcounter_counterName);
int pki;
if (pk == null) {
pki = size(tablename);
} else {
pki = (int) (ByteArray.parseDecimal(pk) + 1);
}
while (true) {
pk = UTF8.getBytes(int2key(pki));
if (!has(tablename, pk)) break;
pki++;
}
return pk;
}
private String int2key(final int i) {
final StringBuilder sb = new StringBuilder(this.keymaxlen);
final String is = Integer.toString(i);
for (int j = 0; j < this.keymaxlen - is.length(); j++) sb.append('0');
sb.append(is);
return sb.toString();
}
/**
* insert a map into a table using a new unique key
* @param tablename
* @param map
* @throws RowSpaceExceededException
* @throws IOException
* @throws RowSpaceExceededException
*/
public byte[] insert(final String tablename, final Map<String, byte[]> map) throws IOException, RowSpaceExceededException {
final byte[] uk = ukey(tablename);
update(tablename, uk, map);
final BEncodedHeap heap = getHeap(system_table_pkcounter);
heap.insert(UTF8.getBytes(tablename), system_table_pkcounter_counterName, uk);
return uk;
}
public void insert(final String table, final byte[] pk, final Map<String, byte[]> map) throws IOException {
final BEncodedHeap heap = getHeap(table);
try {
heap.insert(pk, map);
} catch (final RowSpaceExceededException e) {
throw new IOException(e.getMessage());
}
}
public void insert(final String table, final Row row) throws IOException {
final BEncodedHeap heap = getHeap(table);
try {
heap.insert(row.pk, row);
} catch (final RowSpaceExceededException e) {
throw new IOException(e.getMessage());
}
}
public void update(final String table, final byte[] pk, final Map<String, byte[]> map) throws IOException {
final BEncodedHeap heap = getHeap(table);
try {
heap.update(pk, map);
} catch (final RowSpaceExceededException e) {
throw new IOException(e.getMessage());
}
}
public void update(final String table, final Row row) throws IOException {
final BEncodedHeap heap = getHeap(table);
try {
heap.update(row.pk, row);
} catch (final RowSpaceExceededException e) {
throw new IOException(e.getMessage());
}
}
public byte[] createRow(final String table) throws IOException, RowSpaceExceededException {
return this.insert(table, new ConcurrentHashMap<String, byte[]>());
}
public Row select(final String table, final byte[] pk) throws IOException, RowSpaceExceededException {
final BEncodedHeap heap = getHeap(table);
if (heap.containsKey(pk)) return new Row(pk, heap.get(pk));
return null;
}
public void delete(final String table, final byte[] pk) throws IOException {
final BEncodedHeap heap = getHeap(table);
heap.delete(pk);
}
public boolean has(final String table, final byte[] key) throws IOException {
final BEncodedHeap heap = getHeap(table);
return heap.containsKey(key);
}
public Iterator<byte[]> keys(final String table) throws IOException {
final BEncodedHeap heap = getHeap(table);
return heap.keys();
}
public Iterator<Row> iterator(final String table) throws IOException {
return new RowIterator(table);
}
public Iterator<Row> iterator(final String table, final String whereColumn, final byte[] whereValue) throws IOException {
return new RowIterator(table, whereColumn, whereValue);
}
public Iterator<Row> iterator(final String table, final String whereColumn, final Pattern wherePattern) throws IOException {
return new RowIterator(table, whereColumn, wherePattern);
}
public Iterator<Row> iterator(final String table, final Pattern wherePattern) throws IOException {
return new RowIterator(table, wherePattern);
}
public Collection<Row> orderByPK(final Iterator<Row> rowIterator, int maxcount) {
final TreeMap<String, Row> sortTree = new TreeMap<String, Row>();
Row row;
while ((maxcount < 0 || maxcount-- > 0) && rowIterator.hasNext()) {
row = rowIterator.next();
sortTree.put(UTF8.String(row.pk), row);
}
return sortTree.values();
}
public Collection<Row> orderBy(final Iterator<Row> rowIterator, int maxcount, final String sortColumn) {
final TreeMap<String, Row> sortTree = new TreeMap<String, Row>();
Row row;
byte[] r;
while ((maxcount < 0 || maxcount-- > 0) && rowIterator.hasNext()) {
row = rowIterator.next();
r = row.get(sortColumn);
if (r == null) {
sortTree.put("0000" + UTF8.String(row.pk), row);
} else {
sortTree.put(UTF8.String(r) + UTF8.String(row.pk), row);
}
}
return sortTree.values();
}
public ArrayList<String> columns(final String table) throws IOException {
final BEncodedHeap heap = getHeap(table);
return heap.columns();
}
public class RowIterator extends LookAheadIterator<Row> implements Iterator<Row> {
private final String whereColumn;
private final byte[] whereValue;
private final Pattern wherePattern;
private final Iterator<Map.Entry<byte[], Map<String, byte[]>>> i;
/**
* iterator that iterates all elements in the given table
* @param table
* @throws IOException
*/
public RowIterator(final String table) throws IOException {
this.whereColumn = null;
this.whereValue = null;
this.wherePattern = null;
final BEncodedHeap heap = getHeap(table);
this.i = heap.iterator();
}
/**
* iterator that iterates all elements in the given table
* where a given column is equal to a given value
* @param table
* @param whereColumn
* @param whereValue
* @throws IOException
*/
public RowIterator(final String table, final String whereColumn, final byte[] whereValue) throws IOException {
assert whereColumn != null || whereValue == null;
this.whereColumn = whereColumn;
this.whereValue = whereValue;
this.wherePattern = null;
final BEncodedHeap heap = getHeap(table);
this.i = heap.iterator();
}
/**
* iterator that iterates all elements in the given table
* where a given column matches with a given value
* @param table
* @param whereColumn
* @param wherePattern
* @throws IOException
*/
public RowIterator(final String table, final String whereColumn, final Pattern wherePattern) throws IOException {
this.whereColumn = whereColumn;
this.whereValue = null;
this.wherePattern = wherePattern == null || wherePattern.toString().length() == 0 ? null : wherePattern;
final BEncodedHeap heap = getHeap(table);
this.i = heap.iterator();
}
/**
* iterator that iterates all elements in the given table
* where any column matches with a given value
* @param table
* @param pattern
* @throws IOException
*/
public RowIterator(final String table, final Pattern pattern) throws IOException {
this.whereColumn = null;
this.whereValue = null;
this.wherePattern = pattern == null || pattern.toString().length() == 0 ? null : pattern;
final BEncodedHeap heap = getHeap(table);
this.i = heap.iterator();
}
@Override
protected Row next0() {
Row r;
while (this.i.hasNext()) {
r = new Row(this.i.next());
if (this.whereValue != null) {
if (ByteBuffer.equals(r.get(this.whereColumn), this.whereValue)) return r;
} else if (this.wherePattern != null) {
if (this.whereColumn == null) {
// shall match any column
for (final byte[] b: r.values()) {
if (this.wherePattern.matcher(UTF8.String(b)).matches()) return r;
}
} else {
// must match the given column
if (this.wherePattern.matcher(UTF8.String(r.get(this.whereColumn))).matches()) return r;
}
} else {
return r;
}
}
return null;
}
}
public static class Data extends LinkedHashMap<String, byte[]> {
private static final long serialVersionUID = 978426054043749337L;
public Data() {
super();
}
private Data(final Map<String, byte[]> map) {
super();
assert map != null;
putAll(map);
}
public void put(final String colname, final String value) {
super.put(colname, UTF8.getBytes(value));
}
public void put(final String colname, final int value) {
super.put(colname, UTF8.getBytes(Integer.toString(value)));
}
public void put(final String colname, final long value) {
super.put(colname, UTF8.getBytes(Long.toString(value)));
}
public void put(final String colname, final Date value) {
super.put(colname, UTF8.getBytes(my_SHORT_MILSEC_FORMATTER.format(value)));
}
public byte[] get(final String colname, final byte[] dflt) {
final byte[] r = this.get(colname);
if (r == null) return dflt;
return r;
}
public String get(final String colname, final String dflt) {
final byte[] r = this.get(colname);
if (r == null) return dflt;
return UTF8.String(r);
}
public int get(final String colname, final int dflt) {
final byte[] r = this.get(colname);
if (r == null) return dflt;
try {
return (int) ByteArray.parseDecimal(r);
} catch (final NumberFormatException e) {
return dflt;
}
}
public long get(final String colname, final long dflt) {
final byte[] r = this.get(colname);
if (r == null) return dflt;
try {
return ByteArray.parseDecimal(r);
} catch (final NumberFormatException e) {
return dflt;
}
}
public Date get(final String colname, final Date dflt) {
final byte[] r = this.get(colname);
if (r == null) return dflt;
try {
return my_SHORT_MILSEC_FORMATTER.parse(UTF8.String(r));
} catch (final ParseException e) {
return dflt;
}
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder(this.size() * 40);
sb.append('{');
for (final Map.Entry<String, byte[]> entry: entrySet()) {
sb.append(entry.getKey()).append('=').append(UTF8.String(entry.getValue())).append(", ");
}
if (sb.length() > 1) sb.setLength(sb.length() - 2);
sb.append('}');
return sb.toString();
}
}
public class Row extends Data {
private static final long serialVersionUID = 978426054043749338L;
private final byte[] pk;
private Row(final Map.Entry<byte[], Map<String, byte[]>> entry) {
super(entry.getValue());
assert entry != null;
assert entry.getKey() != null;
assert entry.getValue() != null;
this.pk = entry.getKey();
}
private Row(final byte[] pk, final Map<String, byte[]> map) {
super(map);
assert pk != null;
assert map != null;
this.pk = pk;
}
private Row(final byte[] pk, final String k0, final byte[] v0) {
super();
assert k0 != null;
assert v0 != null;
this.put(k0, v0);
this.pk = pk;
}
public byte[] getPK() {
return this.pk;
}
@Override
public String toString() {
final StringBuilder sb = new StringBuilder(Tables.this.keymaxlen + 20 * this.size());
sb.append(UTF8.String(this.pk)).append(":").append(super.toString());
return sb.toString();
}
}
public static void main(final String[] args) {
// test the class
final File f = new File(new File("maptest").getAbsolutePath());
// System.out.println(f.getAbsolutePath());
// System.out.println(f.getParent());
try {
final Tables map = new Tables(f.getParentFile(), 4);
// put some values into the map
final Map<String, byte[]> m = new HashMap<String, byte[]>();
m.put("k", "000".getBytes());
map.update("testdao", "123".getBytes(), m);
m.put("k", "111".getBytes());
map.update("testdao", "456".getBytes(), m);
m.put("k", "222".getBytes());
map.update("testdao", "789".getBytes(), m);
// iterate over keys
final Iterator<Row> i = map.iterator("testdao");
while (i.hasNext()) {
System.out.println(i.next().toString());
}
// clean up
map.close();
} catch (final IOException e) {
Log.logException(e);
}
}
}