package org.apache.lucene.store.je;
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IndexInput;
import org.apache.lucene.store.IndexOutput;
import org.apache.lucene.store.Lock;
import com.sleepycat.je.Cursor;
import com.sleepycat.je.Database;
import com.sleepycat.je.DatabaseEntry;
import com.sleepycat.je.DatabaseException;
import com.sleepycat.je.OperationStatus;
import com.sleepycat.je.Transaction;
/**
* Port of Andi Vajda's DbDirectory to to Java Edition of Berkeley Database
*
* A JEDirectory is a Berkeley DB JE based implementation of
* {@link org.apache.lucene.store.Directory Directory}. It uses two
* {@link com.sleepycat.je.Database Db} database handles, one for storing file
* records and another for storing file data blocks.
*
* @author Aaron Donovan
*/
public class JEDirectory extends Directory {
protected Set openFiles = Collections.synchronizedSet(new HashSet());
protected Database files, blocks;
protected Transaction txn;
protected int flags;
/**
* Instantiate a DbDirectory. The same threading rules that apply to
* Berkeley DB handles apply to instances of DbDirectory.
*
* @param txn
* a transaction handle that is going to be used for all db
* operations done by this instance. This parameter may be
* <code>null</code>.
* @param files
* a db handle to store file records.
* @param blocks
* a db handle to store file data blocks.
* @param flags
* flags used for db read operations.
*/
public JEDirectory(Transaction txn, Database files, Database blocks,
int flags) {
super();
this.txn = txn;
this.files = files;
this.blocks = blocks;
this.flags = flags;
}
public JEDirectory(Transaction txn, Database files, Database blocks) {
this(txn, files, blocks, 0);
}
public void close() throws IOException {
flush();
}
/**
* Flush the currently open files. After they have been flushed it is safe
* to commit the transaction without closing this DbDirectory instance
* first.
*
* @see #setTransaction
*/
public void flush() throws IOException {
Iterator iterator = openFiles.iterator();
while (iterator.hasNext()) {
System.out
.println(((JEIndexOutput) iterator.next()).file.getName());
// ((IndexOutput) iterator.next()).flush();
}
}
public IndexOutput createOutput(String name) throws IOException {
return new JEIndexOutput(this, name, true);
}
public void deleteFile(String name) throws IOException {
new File(name).delete(this);
}
public boolean fileExists(String name) throws IOException {
return new File(name).exists(this);
}
public long fileLength(String name) throws IOException {
File file = new File(name);
if (file.exists(this))
return file.getLength();
throw new IOException("File does not exist: " + name);
}
public long fileModified(String name) throws IOException {
File file = new File(name);
if (file.exists(this))
return file.getTimeModified();
throw new IOException("File does not exist: " + name);
}
public String[] list() throws IOException {
Cursor cursor = null;
List list = new ArrayList();
try {
try {
DatabaseEntry key = new DatabaseEntry(new byte[0]);
DatabaseEntry data = new DatabaseEntry(null);
data.setPartial(true);
// TODO see if cursor needs configuration
cursor = files.openCursor(txn, null);
// TODO see if LockMode should be set
if (cursor.getNext(key, data, null) != OperationStatus.NOTFOUND) {
ByteArrayInputStream buffer = new ByteArrayInputStream(key
.getData());
DataInputStream in = new DataInputStream(buffer);
String name = in.readUTF();
in.close();
list.add(name);
while (cursor.getNext(key, data, null) != OperationStatus.NOTFOUND) {
buffer = new ByteArrayInputStream(key.getData());
in = new DataInputStream(buffer);
name = in.readUTF();
in.close();
list.add(name);
}
}
} finally {
if (cursor != null)
cursor.close();
}
} catch (DatabaseException e) {
throw new IOException(e.getMessage());
}
return (String[]) list.toArray(new String[list.size()]);
}
public IndexInput openInput(String name) throws IOException {
return new JEIndexInput(this, name);
}
public Lock makeLock(String name) {
return new JELock();
}
public void renameFile(String from, String to) throws IOException {
new File(from).rename(this, to);
}
public void touchFile(String name) throws IOException {
File file = new File(name);
long length = 0L;
if (file.exists(this))
length = file.getLength();
file.modify(this, length, System.currentTimeMillis());
}
/**
* Once a transaction handle was committed it is no longer valid. In order
* to continue using this JEDirectory instance after a commit, the
* transaction handle has to be replaced.
*
* @param txn
* the new transaction handle to use
*/
public void setTransaction(Transaction txn) {
this.txn = txn;
}
}
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