// kelondroRAMIndex.java
// (C) 2008 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 07.01.2008 on http://yacy.net
//
// $LastChangedDate: 2006-04-02 22:40:07 +0200 (So, 02 Apr 2006) $
// $LastChangedRevision: 1986 $
// $LastChangedBy: orbiter $
//
// 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 de.anomic.kelondro;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import de.anomic.kelondro.kelondroRow.Entry;
public class kelondroRAMIndex implements kelondroIndex {
private final kelondroRow rowdef;
private kelondroRowSet index0, index1;
private final kelondroRow.EntryComparator entryComparator;
public kelondroRAMIndex(final kelondroRow rowdef, final int initialspace) {
this.rowdef = rowdef;
this.entryComparator = new kelondroRow.EntryComparator(rowdef.objectOrder);
reset(initialspace);
}
public void clear() {
reset(0);
}
public void reset(final int initialspace) {
this.index0 = null; // first flush RAM to make room
this.index0 = new kelondroRowSet(rowdef, initialspace);
this.index1 = null; // to show that this is the initialization phase
}
public kelondroRow row() {
return index0.row();
}
private final void finishInitialization() {
if (index1 == null) {
// finish initialization phase
index0.sort();
index0.uniq();
index1 = new kelondroRowSet(rowdef, 0);
}
}
public synchronized kelondroRow.Entry get(final byte[] key) {
assert (key != null);
finishInitialization();
final kelondroRow.Entry indexentry = index0.get(key);
if (indexentry != null) return indexentry;
return index1.get(key);
}
public boolean has(final byte[] key) {
assert (key != null);
finishInitialization();
if (index0.has(key)) return true;
return index1.has(key);
}
public synchronized kelondroRow.Entry put(final kelondroRow.Entry entry) {
assert (entry != null);
finishInitialization();
// if the new entry is within the initialization part, just overwrite it
final kelondroRow.Entry indexentry = index0.get(entry.getPrimaryKeyBytes());
if (indexentry != null) {
index0.put(entry);
return indexentry;
}
// else place it in the index1
return index1.put(entry);
}
public Entry put(final Entry row, final Date entryDate) {
return put(row);
}
public void putMultiple(final List<Entry> rows) {
final Iterator<Entry> i = rows.iterator();
while (i.hasNext()) {
put(i.next());
}
}
public synchronized boolean addUnique(final kelondroRow.Entry entry) {
assert (entry != null);
if (index1 == null) {
// we are in the initialization phase
return index0.addUnique(entry);
}
// initialization is over, add to secondary index
return index1.addUnique(entry);
}
public int addUniqueMultiple(final List<Entry> rows) {
final Iterator<Entry> i = rows.iterator();
int c = 0;
while (i.hasNext()) {
if (addUnique(i.next())) c++;
}
return c;
}
public synchronized ArrayList<kelondroRowCollection> removeDoubles() {
// finish initialization phase explicitely
if (index1 == null) index1 = new kelondroRowSet(rowdef, 0);
return index0.removeDoubles();
}
public synchronized kelondroRow.Entry remove(final byte[] key) {
finishInitialization();
// if the new entry is within the initialization part, just delete it
final kelondroRow.Entry indexentry = index0.remove(key);
if (indexentry != null) {
assert index0.get(key) == null; // check if remove worked
return indexentry;
}
// else remove it from the index1
final kelondroRow.Entry removed = index1.remove(key);
assert index1.get(key) == null : "removed " + ((removed == null) ? " is null" : " is not null") + ", and index entry still exists"; // check if remove worked
return removed;
}
public synchronized kelondroRow.Entry removeOne() {
if ((index1 != null) && (index1.size() != 0)) {
return index1.removeOne();
}
if ((index0 != null) && (index0.size() != 0)) {
return index0.removeOne();
}
return null;
}
public synchronized int size() {
if ((index0 != null) && (index1 == null)) {
return index0.size();
}
if ((index0 == null) && (index1 != null)) {
return index1.size();
}
assert ((index0 != null) && (index1 != null));
return index0.size() + index1.size();
}
public synchronized kelondroCloneableIterator<byte[]> keys(final boolean up, final byte[] firstKey) {
// returns the key-iterator of the underlying kelondroIndex
if (index1 == null) {
// finish initialization phase
index0.sort();
index0.uniq();
index1 = new kelondroRowSet(rowdef, 0);
return index0.keys(up, firstKey);
}
assert (index1 != null);
if (index0 == null) {
//assert consistencyAnalysis0() : "consistency problem: " + consistencyAnalysis();
return index1.keys(up, firstKey);
}
// index0 should be sorted
// sort index1 to enable working of the merge iterator
index1.sort();
//assert consistencyAnalysis0() : "consistency problem: " + consistencyAnalysis();
return new kelondroMergeIterator<byte[]>(
index0.keys(up, firstKey),
index1.keys(up, firstKey),
rowdef.objectOrder,
kelondroMergeIterator.simpleMerge,
true);
}
public synchronized kelondroCloneableIterator<kelondroRow.Entry> rows(final boolean up, final byte[] firstKey) {
// returns the row-iterator of the underlying kelondroIndex
if (index1 == null) {
// finish initialization phase
index0.sort();
index0.uniq();
index1 = new kelondroRowSet(rowdef, 0);
return index0.rows(up, firstKey);
}
assert (index1 != null);
if (index0 == null) {
//assert consistencyAnalysis0() : "consistency problem: " + consistencyAnalysis();
return index1.rows(up, firstKey);
}
// index0 should be sorted
// sort index1 to enable working of the merge iterator
index1.sort();
//assert consistencyAnalysis0() : "consistency problem: " + consistencyAnalysis();
return new kelondroMergeIterator<kelondroRow.Entry>(
index0.rows(up, firstKey),
index1.rows(up, firstKey),
entryComparator,
kelondroMergeIterator.simpleMerge,
true);
}
public kelondroProfile profile() {
if (index0 == null) return index1.profile();
if (index1 == null) return index0.profile();
return kelondroProfile.consolidate(index0.profile(), index1.profile());
}
public synchronized void close() {
if (index0 != null) index0.close();
if (index1 != null) index1.close();
}
public String filename() {
return null; // this does not have a file name
}
public void deleteOnExit() {
// do nothing, there is no file
}
}