HADOOP-6226. Moves BoundedByteArrayOutputStream from the tfile package to the io package and makes it available to other users (MAPREDUCE-318). Contributed by Jothi Padmanabhan.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@810451 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Devaraj Das 2009-09-02 11:07:27 +00:00
parent 9ea11c5fb3
commit a3c52b93ea
4 changed files with 121 additions and 2 deletions

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@ -162,6 +162,10 @@ Trunk (unreleased changes)
HADOOP-6120. Add support for Avro specific and reflect data.
(sharad via cutting)
HADOOP-6226. Moves BoundedByteArrayOutputStream from the tfile package to
the io package and makes it available to other users (MAPREDUCE-318).
(Jothi Padmanabhan via ddas)
IMPROVEMENTS
HADOOP-4565. Added CombineFileInputFormat to use data locality information

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@ -15,7 +15,7 @@
* the License.
*/
package org.apache.hadoop.io.file.tfile;
package org.apache.hadoop.io;
import java.io.EOFException;
import java.io.IOException;
@ -26,15 +26,26 @@
* than the buffer capacity. The object can be reused through <code>reset</code>
* API and choose different limits in each round.
*/
class BoundedByteArrayOutputStream extends OutputStream {
public class BoundedByteArrayOutputStream extends OutputStream {
private final byte[] buffer;
private int limit;
private int count;
/**
* Create a BoundedByteArrayOutputStream with the specified
* capacity
* @param capacity The capacity of the underlying byte array
*/
public BoundedByteArrayOutputStream(int capacity) {
this(capacity, capacity);
}
/**
* Create a BoundedByteArrayOutputStream with the specified
* capacity and limit.
* @param capacity The capacity of the underlying byte array
* @param limit The maximum limit upto which data can be written
*/
public BoundedByteArrayOutputStream(int capacity, int limit) {
if ((capacity < limit) || (capacity | limit) < 0) {
throw new IllegalArgumentException("Invalid capacity/limit");
@ -69,6 +80,10 @@ public void write(byte b[], int off, int len) throws IOException {
count += len;
}
/**
* Reset the limit
* @param newlim New Limit
*/
public void reset(int newlim) {
if (newlim > buffer.length) {
throw new IndexOutOfBoundsException("Limit exceeds buffer size");
@ -77,19 +92,27 @@ public void reset(int newlim) {
this.count = 0;
}
/** Reset the buffer */
public void reset() {
this.limit = buffer.length;
this.count = 0;
}
/** Return the current limit */
public int getLimit() {
return limit;
}
/** Returns the underlying buffer.
* Data is only valid to {@link #size()}.
*/
public byte[] getBuffer() {
return buffer;
}
/** Returns the length of the valid data
* currently in the buffer.
*/
public int size() {
return count;
}

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@ -34,6 +34,7 @@
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.io.BoundedByteArrayOutputStream;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.DataInputBuffer;
import org.apache.hadoop.io.DataOutputBuffer;

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@ -0,0 +1,91 @@
/**
* 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.io;
import java.io.IOException;
import junit.framework.TestCase;
import java.util.Arrays;
import java.util.Random;
/** Unit tests for BoundedByteArrayOutputStream */
public class TestBoundedByteArrayOutputStream extends TestCase {
private static final int SIZE = 1024;
private static final byte[] INPUT = new byte[SIZE];
static {
new Random().nextBytes(INPUT);
}
public void testBoundedStream() throws IOException {
BoundedByteArrayOutputStream stream =
new BoundedByteArrayOutputStream(SIZE);
// Write to the stream, get the data back and check for contents
stream.write(INPUT, 0, SIZE);
assertTrue("Array Contents Mismatch",
Arrays.equals(INPUT, stream.getBuffer()));
// Try writing beyond end of buffer. Should throw an exception
boolean caughtException = false;
try {
stream.write(INPUT[0]);
} catch (Exception e) {
caughtException = true;
}
assertTrue("Writing beyond limit did not throw an exception",
caughtException);
//Reset the stream and try, should succeed
stream.reset();
assertTrue("Limit did not get reset correctly",
(stream.getLimit() == SIZE));
stream.write(INPUT, 0, SIZE);
assertTrue("Array Contents Mismatch",
Arrays.equals(INPUT, stream.getBuffer()));
// Try writing one more byte, should fail
caughtException = false;
try {
stream.write(INPUT[0]);
} catch (Exception e) {
caughtException = true;
}
// Reset the stream, but set a lower limit. Writing beyond
// the limit should throw an exception
stream.reset(SIZE - 1);
assertTrue("Limit did not get reset correctly",
(stream.getLimit() == SIZE -1));
caughtException = false;
try {
stream.write(INPUT, 0, SIZE);
} catch (Exception e) {
caughtException = true;
}
assertTrue("Writing beyond limit did not throw an exception",
caughtException);
}
}