Author: atm
Date: Sat Mar 3 02:02:23 2012
New Revision: 1296556
URL: http://svn.apache.org/viewvc?rev=1296556&view=rev
Log:
HADOOP-8135. Add ByteBufferReadable interface to FSDataInputStream. Contributed
by Henry Robinson.
Added:
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ByteBufferReadable.java
Modified:
hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java
Modified: hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt?rev=1296556&r1=1296555&r2=1296556&view=diff
==============================================================================
--- hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt
(original)
+++ hadoop/common/trunk/hadoop-common-project/hadoop-common/CHANGES.txt Sat Mar
3 02:02:23 2012
@@ -14,6 +14,9 @@ Trunk (unreleased changes)
Bikas Saha, Suresh Srinivas, Jitendra Nath Pandey, Hari Mankude, Brandon
Li,
Sanjay Radia, Mingjie Lai, and Gregory Chanan
+ HADOOP-8135. Add ByteBufferReadable interface to FSDataInputStream. (Henry
+ Robinson via atm)
+
IMPROVEMENTS
HADOOP-8017. Configure hadoop-main pom to get rid of M2E plugin execution
Added:
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ByteBufferReadable.java
URL:
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ByteBufferReadable.java?rev=1296556&view=auto
==============================================================================
---
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ByteBufferReadable.java
(added)
+++
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/ByteBufferReadable.java
Sat Mar 3 02:02:23 2012
@@ -0,0 +1,45 @@
+/**
+ * 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.fs;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+
+/**
+ * Implementers of this interface provide a read API that writes to a
+ * ByteBuffer, not a byte[].
+ */
+public interface ByteBufferReadable {
+ /**
+ * Reads up to buf.remaining() bytes into buf. Callers should use
+ * buf.limit(..) to control the size of the desired read.
+ *
+ * After the call, buf.position() should be unchanged, and therefore any data
+ * can be immediately read from buf.
+ *
+ * Many implementations will throw {@link UnsupportedOperationException}, so
+ * callers that are not confident in support for this method from the
+ * underlying filesystem should be prepared to handle that exception.
+ *
+ * @param buf
+ * the ByteBuffer to receive the results of the read operation
+ * @return the number of bytes available to read from buf
+ * @throws IOException if there is some error performing the read
+ */
+ public int read(ByteBuffer buf) throws IOException;
+}
Modified:
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java
URL:
http://svn.apache.org/viewvc/hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java?rev=1296556&r1=1296555&r2=1296556&view=diff
==============================================================================
---
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java
(original)
+++
hadoop/common/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java
Sat Mar 3 02:02:23 2012
@@ -18,6 +18,7 @@
package org.apache.hadoop.fs;
import java.io.*;
+import java.nio.ByteBuffer;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
@@ -27,7 +28,7 @@ import org.apache.hadoop.classification.
@InterfaceAudience.Public
@InterfaceStability.Stable
public class FSDataInputStream extends DataInputStream
- implements Seekable, PositionedReadable, Closeable {
+ implements Seekable, PositionedReadable, Closeable, ByteBufferReadable {
public FSDataInputStream(InputStream in)
throws IOException {
@@ -116,4 +117,12 @@ public class FSDataInputStream extends D
public InputStream getWrappedStream() {
return in;
}
+
+ public int read(ByteBuffer buf) throws IOException {
+ if (in instanceof ByteBufferReadable) {
+ return ((ByteBufferReadable)in).read(buf);
+ }
+
+ throw new UnsupportedOperationException("Byte-buffer read unsupported by
input stream");
+ }
}
