/**
* HandleMap
* Copyright 2008 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
* First released 08.04.2008 at http://yacy.net
*
* $LastChangedDate: 2011-06-23 13:57:17 +0200 (Do, 23. Jun 2011) $
* $LastChangedRevision: 7794 $
* $LastChangedBy: orbiter $
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program in the file lgpl21.txt
* If not, see <http://www.gnu.org/licenses/>.
*/
package net.yacy.kelondro.index;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.order.ByteOrder;
import net.yacy.kelondro.order.CloneableIterator;
public final class HandleMap implements Iterable<Row.Entry> {
private final Row rowdef;
private RAMIndexCluster index;
/**
* initialize a HandleMap
* This may store a key and a long value for each key.
* The class is used as index for database files
* @param keylength
* @param objectOrder
* @param space
*/
public HandleMap(final int keylength, final ByteOrder objectOrder, final int idxbytes, final int expectedspace, final String name) {
this.rowdef = new Row(new Column[]{new Column("key", Column.celltype_binary, Column.encoder_bytes, keylength, "key"), new Column("long c-" + idxbytes + " {b256}")}, objectOrder);
this.index = new RAMIndexCluster(name, this.rowdef, spread(expectedspace));
}
/**
* initialize a HandleMap with the content of a dumped index
* @param keylength
* @param objectOrder
* @param file
* @throws IOException
* @throws RowSpaceExceededException
*/
public HandleMap(final int keylength, final ByteOrder objectOrder, final int idxbytes, final File file) throws IOException, RowSpaceExceededException {
this(keylength, objectOrder, idxbytes, (int) (file.length() / (keylength + idxbytes)), file.getAbsolutePath());
// read the index dump and fill the index
InputStream is;
try {
is = new BufferedInputStream(new FileInputStream(file), 1024 * 1024);
} catch (final OutOfMemoryError e) {
is = new FileInputStream(file);
}
if (file.getName().endsWith(".gz")) is = new GZIPInputStream(is);
final byte[] a = new byte[keylength + idxbytes];
int c;
Row.Entry entry;
while (true) {
c = is.read(a);
if (c <= 0) break;
entry = this.rowdef.newEntry(a); // may be null if a is not well-formed
if (entry != null) this.index.addUnique(entry);
}
is.close();
is = null;
assert this.index.size() == file.length() / (keylength + idxbytes);
}
public void trim() {
this.index.trim();
}
public long mem() {
return this.index.mem();
}
private static final int spread(final int expectedspace) {
return Math.min(Runtime.getRuntime().availableProcessors(), Math.max(1, expectedspace / 3000));
}
public final int[] saturation() {
int keym = 0;
int valm = this.rowdef.width(1);
int valc;
byte[] lastk = null, thisk;
for (final Row.Entry row: this) {
// check length of key
if (lastk == null) {
lastk = row.bytes();
} else {
thisk = row.bytes();
keym = Math.max(keym, eq(lastk, thisk));
lastk = thisk;
}
// check length of value
for (valc = this.rowdef.primaryKeyLength; valc < this.rowdef.objectsize; valc++) {
if (lastk[valc] != 0) break;
} // valc is the number of leading zeros plus primaryKeyLength
valm = Math.min(valm, valc - this.rowdef.primaryKeyLength); // valm is the number of leading zeros
}
return new int[]{keym, this.rowdef.width(1) - valm};
}
private final int eq(final byte[] a, final byte[] b) {
for (int i = 0; i < a.length; i++) {
if (a[i] != b[i]) return i;
}
return a.length;
}
/**
* write a dump of the index to a file. All entries are written in order
* which makes it possible to read them again in a fast way
* @param file
* @return the number of written entries
* @throws IOException
*/
public final int dump(final File file) throws IOException {
// we must use an iterator from the combined index, because we need the entries sorted
// otherwise we could just write the byte[] from the in kelondroRowSet which would make
// everything much faster, but this is not an option here.
final File tmp = new File(file.getParentFile(), file.getName() + ".prt");
final Iterator<Row.Entry> i = this.index.rows(true, null);
OutputStream os;
try {
os = new BufferedOutputStream(new FileOutputStream(tmp), 4 * 1024 * 1024);
} catch (final OutOfMemoryError e) {
os = new FileOutputStream(tmp);
}
if (file.getName().endsWith(".gz")) os = new GZIPOutputStream(os);
int c = 0;
while (i.hasNext()) {
os.write(i.next().bytes());
c++;
}
os.flush();
os.close();
tmp.renameTo(file);
assert file.exists() : file.toString();
assert !tmp.exists() : tmp.toString();
return c;
}
public final Row row() {
return this.index.row();
}
public final void clear() {
this.index.clear();
}
public final byte[] smallestKey() {
return this.index.smallestKey();
}
public final byte[] largestKey() {
return this.index.largestKey();
}
public final boolean has(final byte[] key) {
assert (key != null);
return this.index.has(key);
}
public final long get(final byte[] key) {
assert (key != null);
final Row.Entry indexentry = this.index.get(key);
if (indexentry == null) return -1;
return indexentry.getColLong(1);
}
/**
* Adds the key-value pair to the index.
* @param key the index key
* @param l the value
* @return the previous entry of the index
* @throws IOException
* @throws RowSpaceExceededException
*/
public final long put(final byte[] key, final long l) throws RowSpaceExceededException {
assert l >= 0 : "l = " + l;
assert (key != null);
final Row.Entry newentry = this.rowdef.newEntry();
newentry.setCol(0, key);
newentry.setCol(1, l);
final Row.Entry oldentry = this.index.replace(newentry);
if (oldentry == null) return -1;
return oldentry.getColLong(1);
}
public final void putUnique(final byte[] key, final long l) throws RowSpaceExceededException {
assert l >= 0 : "l = " + l;
assert (key != null);
final Row.Entry newentry = this.rowdef.newEntry();
newentry.setCol(0, key);
newentry.setCol(1, l);
this.index.addUnique(newentry);
}
public final long add(final byte[] key, final long a) throws RowSpaceExceededException {
assert key != null;
assert a > 0; // it does not make sense to add 0. If this occurres, it is a performance issue
synchronized (this.index) {
final Row.Entry indexentry = this.index.get(key);
if (indexentry == null) {
final Row.Entry newentry = this.rowdef.newEntry();
newentry.setCol(0, key);
newentry.setCol(1, a);
this.index.addUnique(newentry);
return 1;
}
final long i = indexentry.getColLong(1) + a;
indexentry.setCol(1, i);
this.index.put(indexentry);
return i;
}
}
public final long inc(final byte[] key) throws RowSpaceExceededException {
return add(key, 1);
}
public final long dec(final byte[] key) throws RowSpaceExceededException {
return add(key, -1);
}
public final ArrayList<long[]> removeDoubles() throws RowSpaceExceededException {
final ArrayList<long[]> report = new ArrayList<long[]>();
long[] is;
int c;
long l;
final int initialSize = size();
final ArrayList<RowCollection> rd = this.index.removeDoubles();
for (final RowCollection rowset: rd) {
is = new long[rowset.size()];
c = 0;
for (final Row.Entry e: rowset) {
l = e.getColLong(1);
assert l < initialSize : "l = " + l + ", initialSize = " + initialSize;
is[c++] = l;
}
report.add(is);
}
return report;
}
public final ArrayList<byte[]> top(final int count) {
final List<Row.Entry> list0 = this.index.top(count);
final ArrayList<byte[]> list = new ArrayList<byte[]>();
for (final Row.Entry entry: list0) {
list.add(entry.getPrimaryKeyBytes());
}
return list;
}
public final synchronized long remove(final byte[] key) {
assert (key != null);
final Row.Entry indexentry;
synchronized (this.index) {
final boolean exist = this.index.has(key);
if (!exist) return -1;
final int s = this.index.size();
final long m = this.index.mem();
indexentry = this.index.remove(key);
assert (indexentry != null);
assert this.index.size() < s : "s = " + s + ", index.size() = " + this.index.size();
assert this.index.mem() <= m : "m = " + m + ", index.mem() = " + this.index.mem();
}
if (indexentry == null) return -1;
return indexentry.getColLong(1);
}
public final long removeone() {
final Row.Entry indexentry = this.index.removeOne();
if (indexentry == null) return -1;
return indexentry.getColLong(1);
}
public final int size() {
return this.index.size();
}
public final boolean isEmpty() {
return this.index.isEmpty();
}
public final CloneableIterator<byte[]> keys(final boolean up, final byte[] firstKey) {
return this.index.keys(up, firstKey);
}
public final CloneableIterator<Row.Entry> rows(final boolean up, final byte[] firstKey) {
return this.index.rows(up, firstKey);
}
public final void close() {
this.index.close();
this.index = null;
}
/**
* this method creates a concurrent thread that can take entries that are used to initialize the map
* it should be used when a HandleMap is initialized when a file is read. Concurrency of FileIO and
* map creation will speed up the initialization process.
* @param keylength
* @param objectOrder
* @param space
* @param bufferSize
* @return
*/
public final static initDataConsumer asynchronusInitializer(final String name, final int keylength, final ByteOrder objectOrder, final int idxbytes, final int expectedspace) {
final initDataConsumer initializer = new initDataConsumer(new HandleMap(keylength, objectOrder, idxbytes, expectedspace, name));
final ExecutorService service = Executors.newSingleThreadExecutor();
initializer.setResult(service.submit(initializer));
service.shutdown();
return initializer;
}
private final static class entry {
public byte[] key;
public long l;
public entry(final byte[] key, final long l) {
this.key = key;
this.l = l;
}
}
protected static final entry poisonEntry = new entry(new byte[0], 0);
public final static class initDataConsumer implements Callable<HandleMap> {
private final BlockingQueue<entry> cache;
private final HandleMap map;
private Future<HandleMap> result;
public initDataConsumer(final HandleMap map) {
this.map = map;
this.cache = new LinkedBlockingQueue<entry>();
}
protected final void setResult(final Future<HandleMap> result) {
this.result = result;
}
/**
* hand over another entry that shall be inserted into the HandleMap with an addl method
* @param key
* @param l
*/
public final void consume(final byte[] key, final long l) {
while (true) try {
this.cache.put(new entry(key, l));
break;
} catch (final InterruptedException e) {
continue;
}
}
/**
* to signal the initialization thread that no more entries will be submitted with consumer()
* this method must be called. The process will not terminate if this is not called before.
*/
public final void finish() {
while (true) try {
this.cache.put(poisonEntry);
break;
} catch (final InterruptedException e) {
continue;
}
}
/**
* this must be called after a finish() was called. this method blocks until all entries
* had been processed, and the content was sorted. It returns the HandleMap
* that the user wanted to initialize
* @return
* @throws InterruptedException
* @throws ExecutionException
*/
public final HandleMap result() throws InterruptedException, ExecutionException {
return this.result.get();
}
public final HandleMap call() throws IOException {
try {
finishloop: while (true) {
entry c;
try {
while ((c = this.cache.take()) != poisonEntry) {
this.map.putUnique(c.key, c.l);
}
break finishloop;
} catch (final InterruptedException e) {
continue finishloop;
}
}
} catch (final RowSpaceExceededException e) {
Log.logException(e);
}
return this.map;
}
public void close() {
this.map.close();
}
}
public Iterator<Row.Entry> iterator() {
return rows(true, null);
}
}