Author: dhruba
Date: Wed Feb 13 21:36:53 2008
New Revision: 627665
URL: http://svn.apache.org/viewvc?rev=627665&view=rev
Log:
HADOOP-2345. New HDFS transactions to support appending
to files. Disk layout version changed from -11 to -12. (dhruba)
Added:
hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java
(with props)
Added: hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java
URL:
http://svn.apache.org/viewvc/hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java?rev=627665&view=auto
==============================================================================
--- hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java
(added)
+++ hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java Wed
Feb 13 21:36:53 2008
@@ -0,0 +1,111 @@
+/**
+ * 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.dfs;
+
+import java.io.*;
+import org.apache.hadoop.io.*;
+
+/****************************************************************
+ * A GenerationStamp is a Hadoop FS primitive, identified by a long.
+ ****************************************************************/
+class GenerationStamp implements WritableComparable {
+
+ static { // register a ctor
+ WritableFactories.setFactory
+ (GenerationStamp.class,
+ new WritableFactory() {
+ public Writable newInstance() { return new GenerationStamp(); }
+ });
+ }
+
+ long genstamp;
+
+ /**
+ * Create a new instance, initialized to 0.
+ */
+ public GenerationStamp() {
+ this.genstamp = 0;
+ }
+
+ /**
+ * Create a new instance, initialized to the specified value.
+ */
+ public GenerationStamp(long stamp) {
+ this.genstamp = stamp;
+ }
+
+ /**
+ * Returns the current generation stamp
+ */
+ public long getStamp() {
+ return this.genstamp;
+ }
+
+ /**
+ * Sets the current generation stamp
+ */
+ public void setStamp(long stamp) {
+ this.genstamp = stamp;
+ }
+
+ /**
+ * Returns the current stamp and incrments the counter
+ */
+ public long nextStamp() {
+ this.genstamp++;
+ return this.genstamp;
+ }
+
+ /////////////////////////////////////
+ // Writable
+ /////////////////////////////////////
+ public void write(DataOutput out) throws IOException {
+ out.writeLong(genstamp);
+ }
+
+ public void readFields(DataInput in) throws IOException {
+ this.genstamp = in.readLong();
+ if (this.genstamp < 0) {
+ throw new IOException("Bad Generation Stamp: " + this.genstamp);
+ }
+ }
+
+ /////////////////////////////////////
+ // Comparable
+ /////////////////////////////////////
+ public int compareTo(Object o) {
+ GenerationStamp b = (GenerationStamp) o;
+ if (genstamp < b.genstamp) {
+ return -1;
+ } else if (genstamp == b.genstamp) {
+ return 0;
+ } else {
+ return 1;
+ }
+ }
+ public boolean equals(Object o) {
+ if (!(o instanceof GenerationStamp)) {
+ return false;
+ }
+ return genstamp == ((GenerationStamp)o).genstamp;
+ }
+
+ public int hashCode() {
+ return 37 * 17 + (int) (genstamp^(genstamp>>>32));
+ }
+}
Propchange:
hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java
------------------------------------------------------------------------------
svn:eol-style = native
Propchange:
hadoop/core/trunk/src/java/org/apache/hadoop/dfs/GenerationStamp.java
------------------------------------------------------------------------------
svn:keywords = Id Revision HeadURL
