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The ActiveMQ Message Broker and Client implementations
/**
* 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.activemq.kaha.impl.async;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import org.apache.activemq.util.IOHelper;
/**
* Allows you to open a data file in read only mode. Useful when working with
* archived data files.
*/
public class ReadOnlyDataFile extends DataFile {
ReadOnlyDataFile(File file, int number, int preferedSize) {
super(file, number, preferedSize);
}
public RandomAccessFile openRandomAccessFile(boolean appender) throws IOException {
RandomAccessFile rc = new RandomAccessFile(file, "r");
// When we start to write files size them up so that the OS has a chance
// to allocate the file contigously.
if (appender) {
if (length < preferedSize) {
rc.setLength(preferedSize);
}
}
return rc;
}
public void closeRandomAccessFile(RandomAccessFile file) throws IOException {
file.close();
}
public synchronized boolean delete() throws IOException {
throw new RuntimeException("Not valid on a read only file.");
}
public synchronized void move(File targetDirectory) throws IOException{
throw new RuntimeException("Not valid on a read only file.");
}
}