/**
* 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.
*/
package org.apache.cassandra.tools;
import java.io.DataOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import org.apache.cassandra.io.DataInputBuffer;
import org.apache.cassandra.io.DataOutputBuffer;
import org.apache.cassandra.io.IFileReader;
import org.apache.cassandra.io.SSTable;
import org.apache.cassandra.io.SequenceFile;
import org.apache.cassandra.io.SSTable.KeyPositionInfo;
import org.apache.cassandra.utils.BasicUtilities;
public class KeyExtracter
{
private static final int bufferSize_ = 64*1024;
public static void main(String[] args) throws Throwable
{
if ( args.length != 3 )
{
System.out.println("Usage : java com.facebook.infrastructure.tools.IndexBuilder <key to extract> <data file> <output file>");
System.exit(1);
}
String keyToExtract = args[0];
String dataFile = args[1];
String outputFile = args[2];
extractKeyIntoFile(keyToExtract, dataFile, outputFile);
}
public static boolean extractKeyIntoFile(String keyToExtract, String dataFile, String outputFile) throws IOException
{
IFileReader dataReader = SequenceFile.bufferedReader(dataFile, bufferSize_);
DataOutputBuffer bufOut = new DataOutputBuffer();
DataInputBuffer bufIn = new DataInputBuffer();
try
{
while ( !dataReader.isEOF() )
{
bufOut.reset();
dataReader.next(bufOut);
bufIn.reset(bufOut.getData(), bufOut.getLength());
/* Key just read */
String key = bufIn.readUTF();
/* check if we want this key */
if ( key.equals(keyToExtract) )
{
int keySize = bufIn.readInt();
byte[] keyData = new byte[keySize];
bufIn.read(keyData, 0, keySize);
/* write the key data into a file */
RandomAccessFile raf = new RandomAccessFile(outputFile, "rw");
raf.writeUTF(key);
raf.writeInt(keySize);
raf.write(keyData);
dumpBlockIndex(keyToExtract, 0L, keySize, raf);
raf.close();
return true;
}
}
}
finally
{
dataReader.close();
}
return false;
}
private static void dumpBlockIndex(String key, long position, long size, RandomAccessFile raf) throws IOException
{
DataOutputBuffer bufOut = new DataOutputBuffer();
/* Number of keys in this block */
bufOut.writeInt(1);
bufOut.writeUTF(key);
bufOut.writeLong(position);
bufOut.writeLong(size);
/* Write out the block index. */
raf.writeUTF(SSTable.blockIndexKey_);
raf.writeInt(bufOut.getLength());
raf.write(bufOut.getData(), 0, bufOut.getLength());
}
}