001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    package org.apache.hadoop.yarn.util;
019    
020    import java.util.Calendar;
021    import java.util.TimeZone;
022    
023    import org.apache.hadoop.classification.InterfaceAudience.Public;
024    import org.apache.hadoop.classification.InterfaceStability.Evolving;
025    
026    /**
027     * Implementation of {@link Clock} that gives the current UTC time in
028     * milliseconds.
029     */
030    @Public
031    @Evolving
032    public class UTCClock implements Clock {
033    
034      private final TimeZone utcZone = TimeZone.getTimeZone("UTC");
035    
036      public long getTime() {
037        return Calendar.getInstance(utcZone).getTimeInMillis();
038      }
039    }