001/**
002 * Copyright 2010-2014 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.common.util;
017
018public class LongCounter {
019
020        long count;
021
022        public LongCounter() {
023                this(0);
024        }
025
026        public LongCounter(long startValue) {
027                super();
028                this.count = startValue;
029        }
030
031        public synchronized long increment() {
032                return increment(1);
033        }
034
035        public synchronized long increment(long amount) {
036                Assert.isTrue(amount > 0, "amount must be > 0");
037                Assert.isTrue(count <= Long.MAX_VALUE - amount, "max value exceeded");
038                return count += amount;
039        }
040
041        public synchronized long decrement(long amount) {
042                Assert.isTrue(amount > 0, "amount must be > 0");
043                Assert.isTrue(count >= Long.MIN_VALUE + amount, "min value exceeded");
044                return count -= amount;
045        }
046
047        public synchronized long decrement() {
048                return decrement(1);
049        }
050
051        public synchronized long getValue() {
052                return count;
053        }
054}