/**
* 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.mapred;
import java.util.Comparator;
/**
* Order {@link JobInProgress} objects by priority and then by submit time, as
* in the default scheduler in Hadoop.
*/
public class FifoJobComparator implements Comparator<JobInProgress> {
public int compare(JobInProgress j1, JobInProgress j2) {
int res = j1.getPriority().compareTo(j2.getPriority());
if (res == 0) {
if (j1.getStartTime() < j2.getStartTime()) {
res = -1;
} else {
res = (j1.getStartTime() == j2.getStartTime() ? 0 : 1);
}
}
if (res == 0) {
res = j1.hashCode() - j2.hashCode();
}
return res;
}
}