/**
* 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.hadoop.hdfs.server.datanode;
import java.io.IOException;
import java.io.File;
import org.apache.hadoop.hdfs.protocol.Block;
public abstract class FSDatasetTestUtil {
/**
* Truncate the given block in place, such that the new truncated block
* is still valid (ie checksums are updated to stay in sync with block file)
*/
public static void truncateBlock(DataNode dn,
Block block,
long newLength)
throws IOException
{
FSDataset ds = (FSDataset)dn.data;
File blockFile = ds.findBlockFile(block.getBlockId());
if (blockFile == null) {
throw new IOException("Can't find block file for block " +
block + " on DN " + dn);
}
File metaFile = FSDataset.findMetaFile(blockFile);
FSDataset.truncateBlock(blockFile, metaFile,
block.getNumBytes(), newLength);
}
public static void truncateBlockFile(File blockFile, long newLength)
throws IOException {
File metaFile = FSDataset.findMetaFile(blockFile);
FSDataset.truncateBlock(blockFile, metaFile,
blockFile.length(), newLength);
}
}