guard against NPE while reading FileTrailer and HFileBlock

guard against NPE from FSInputStream#seek

Signed-off-by: Michael Stack <stack@apache.org>
This commit is contained in:
James Moore 2017-02-24 10:26:12 -05:00 committed by Michael Stack
parent 35d7a0cd07
commit 201c838250
3 changed files with 46 additions and 2 deletions

View File

@ -388,7 +388,8 @@ public class FixedFileTrailer {
bufferSize = (int) fileSize;
}
istream.seek(seekPoint);
HFileUtil.seekOnMultipleSources(istream, seekPoint);
ByteBuffer buf = ByteBuffer.allocate(bufferSize);
istream.readFully(buf.array(), buf.arrayOffset(),
buf.arrayOffset() + buf.limit());

View File

@ -1512,7 +1512,7 @@ public class HFileBlock implements Cacheable {
if (!pread && streamLock.tryLock()) {
// Seek + read. Better for scanning.
try {
istream.seek(fileOffset);
HFileUtil.seekOnMultipleSources(istream, fileOffset);
long realOffset = istream.getPos();
if (realOffset != fileOffset) {

View File

@ -0,0 +1,43 @@
/**
* 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.hbase.io.hfile;
import java.io.IOException;
import org.apache.hadoop.fs.FSDataInputStream;
public class HFileUtil {
/** guards against NullPointer
* utility which tries to seek on the DFSIS and will try an alternative source
* if the FSDataInputStream throws an NPE HBASE-17501
* @param istream
* @param offset
* @throws IOException
*/
static public void seekOnMultipleSources(FSDataInputStream istream, long offset) throws IOException {
try {
// attempt to seek inside of current blockReader
istream.seek(offset);
} catch (NullPointerException e) {
// retry the seek on an alternate copy of the data
// this can occur if the blockReader on the DFSInputStream is null
istream.seekToNewSource(offset);
}
}
}