// Copyright 2009, 2011 The Apache Software Foundation
//
// 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.
package org.apache.tapestry5.ioc.internal.util;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* Internal utilities for identifying the JDK version, used in the rare cases
* that we are patching around JDK bugs.
*/
public class JDKUtils
{
/**
* Is the running JVM JDK 1.5?
*/
public static final boolean JDK_1_5 = isVersion("1.5");
private static boolean isVersion(String versionId)
{
return System.getProperty("java.specification.version").equals(versionId);
}
/**
* Returns a {@link ReentrantLock} used to serialize access to the construction of a thread local; this is only needed under JDK 1.5 (due to a bug in the JDK);
* for other JDKs, a {@link DummyLock} is returned.
*
* @return lock to use when creating
* @since 5.3
* @deprecated Deprecated in 5.4 with no replacement.
*/
public static Lock createLockForThreadLocalCreation()
{
return JDK_1_5 ? new ReentrantLock() : new DummyLock();
}
}