org.apache.hadoop.mapreduce.Counter Maven / Gradle / Ivy
/**
* 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.
*
* Counters
represent global counters, defined either by the
* Map-Reduce framework or applications. Each Counter
is named by
* an {@link Enum} and has a long for the value.
*
* Counters
are bunched into Groups, each comprising of
* counters from a particular Enum
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();
}