Mega Code Archive
Atomic Utils
<![CDATA[
/*
* @(#)$Id: codetemplate_xbird.xml 943 2006-09-13 07:03:37Z yui $
*
* Copyright 2006-2008 Makoto YUI
*
* Licensed 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.
*
* Contributors:
* Makoto YUI - initial implementation
*/
//package xbird.util.concurrent;
import java.util.concurrent.atomic.AtomicInteger;
/**
*
* <DIV lang="en"></DIV>
* <DIV lang="ja"></DIV>
*
* @author Makoto YUI (yuin405+xbird@gmail.com)
*/
public final class AtomicUtils {
private AtomicUtils() {}
public static boolean tryIncrementIfLessThan(final AtomicInteger capacity, final int atmost) {
int capa;
do {
capa = capacity.get();
if(capa >= atmost) {
return false;
}
} while(!capacity.compareAndSet(capa, capa + 1));
return true;
}
public static int tryIncrementAndGetIfLessThan(final AtomicInteger capacity, final int upperbound) {
for(;;) {
final int current = capacity.get();
if(current >= upperbound) {
return upperbound;
}
final int next = current + 1;
if(capacity.compareAndSet(current, next)) {
return next;
}
}
}
public static boolean tryIncrementIfGreaterThan(final AtomicInteger capacity, final int least) {
int capa;
do {
capa = capacity.get();
if(capa <= least) {
return false;
}
} while(!capacity.compareAndSet(capa, capa + 1));
return true;
}
public static boolean tryDecrementIfGreaterThan(final AtomicInteger capacity, final int least) {
int capa;
do {
capa = capacity.get();
if(capa <= least) {
return false;
}
} while(!capacity.compareAndSet(capa, capa - 1));
return true;
}
public static int tryDecrementAndGetIfGreaterThan(final AtomicInteger capacity, final int least) {
for(;;) {
final int current = capacity.get();
if(current <= least) {
return current;
}
final int next = current - 1;
if(capacity.compareAndSet(current, next)) {
return next;
}
}
}
}
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