| /** |
| * 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 org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.classification.InterfaceAudience.Private; |
| import org.apache.hadoop.io.Writable; |
| |
| /** |
| * 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. |
| */ |
| @InterfaceAudience.Public |
| @InterfaceStability.Stable |
| public interface Counter extends Writable { |
| |
| /** |
| * Set the display name of the counter |
| * @param displayName of the counter |
| * @deprecated (and no-op by default) |
| */ |
| @Deprecated |
| void setDisplayName(String displayName); |
| |
| /** |
| * @return the name of the counter |
| */ |
| String getName(); |
| |
| /** |
| * Get the display name of the counter. |
| * @return the user facing name of the counter |
| */ |
| String getDisplayName(); |
| |
| /** |
| * What is the current value of this counter? |
| * @return the current value |
| */ |
| long getValue(); |
| |
| /** |
| * Set this counter by the given value |
| * @param value the value to set |
| */ |
| void setValue(long value); |
| |
| /** |
| * Increment this counter by the given value |
| * @param incr the value to increase this counter by |
| */ |
| void increment(long incr); |
| |
| @Private |
| /** |
| * Return the underlying object if this is a facade. |
| * @return the undelying object. |
| */ |
| Counter getUnderlyingCounter(); |
| } |