| /** |
| * 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.mapreduce; |
| |
| import java.io.IOException; |
| import java.io.DataInput; |
| import java.io.DataOutput; |
| |
| import org.apache.hadoop.io.Text; |
| import org.apache.hadoop.io.Writable; |
| import org.apache.hadoop.io.WritableUtils; |
| |
| /** |
| * A named counter that tracks the progress of a map/reduce job. |
| * |
| * <p><code>Counters</code> represent global counters, defined either by the |
| * Map-Reduce framework or applications. Each <code>Counter</code> is named by |
| * an {@link Enum} and has a long for the value.</p> |
| * |
| * <p><code>Counters</code> are bunched into Groups, each comprising of |
| * counters from a particular <code>Enum</code> class. |
| */ |
| public class Counter implements Writable { |
| |
| private String name; |
| private String displayName; |
| private long value = 0; |
| |
| protected Counter() { |
| } |
| |
| protected Counter(String name, String displayName) { |
| this.name = name; |
| this.displayName = displayName; |
| } |
| |
| /** Create a counter. |
| * @param name the name within the group's enum. |
| * @param displayName a name to be displayed. |
| * @param value the counter value. |
| */ |
| public Counter(String name, String displayName, long value) { |
| this.name = name; |
| this.displayName = displayName; |
| this.value = value; |
| } |
| |
| @Deprecated |
| protected synchronized void setDisplayName(String displayName) { |
| this.displayName = displayName; |
| } |
| |
| /** |
| * Read the binary representation of the counter |
| */ |
| @Override |
| public synchronized void readFields(DataInput in) throws IOException { |
| name = Text.readString(in); |
| if (in.readBoolean()) { |
| displayName = Text.readString(in); |
| } else { |
| displayName = name; |
| } |
| value = WritableUtils.readVLong(in); |
| } |
| |
| /** |
| * Write the binary representation of the counter |
| */ |
| @Override |
| public synchronized void write(DataOutput out) throws IOException { |
| Text.writeString(out, name); |
| boolean distinctDisplayName = ! name.equals(displayName); |
| out.writeBoolean(distinctDisplayName); |
| if (distinctDisplayName) { |
| Text.writeString(out, displayName); |
| } |
| WritableUtils.writeVLong(out, value); |
| } |
| |
| public synchronized String getName() { |
| return name; |
| } |
| |
| /** |
| * Get the name of the counter. |
| * @return the user facing name of the counter |
| */ |
| public synchronized String getDisplayName() { |
| return displayName; |
| } |
| |
| /** |
| * What is the current value of this counter? |
| * @return the current value |
| */ |
| public synchronized long getValue() { |
| return value; |
| } |
| |
| /** |
| * Increment this counter by the given value |
| * @param incr the value to increase this counter by |
| */ |
| public synchronized void increment(long incr) { |
| value += incr; |
| } |
| |
| @Override |
| public synchronized boolean equals(Object genericRight) { |
| if (genericRight instanceof Counter) { |
| synchronized (genericRight) { |
| Counter right = (Counter) genericRight; |
| return name.equals(right.name) && |
| displayName.equals(right.displayName) && |
| value == right.value; |
| } |
| } |
| return false; |
| } |
| |
| @Override |
| public synchronized int hashCode() { |
| return name.hashCode() + displayName.hashCode(); |
| } |
| } |