org.apache.logging.log4j.core.util.internal.UnsafeUtil Maven / Gradle / Ivy
/*
* 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.logging.log4j.core.util.internal;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.status.StatusLogger;
/**
* Provides access to unsafe operations.
*/
public class UnsafeUtil {
private static final Logger LOGGER = StatusLogger.getLogger();
private static Method cleanerMethod;
private static Method cleanMethod;
static {
try {
AccessController.doPrivileged(new PrivilegedExceptionAction() {
@Override
public Void run() throws ReflectiveOperationException, SecurityException {
final ByteBuffer direct = ByteBuffer.allocateDirect(1);
cleanerMethod = direct.getClass().getDeclaredMethod("cleaner");
cleanerMethod.setAccessible(true);
final Object cleaner = cleanerMethod.invoke(direct);
cleanMethod = cleaner.getClass().getMethod("clean");
return null;
}
});
} catch (PrivilegedActionException e) {
final Exception wrapped = e.getException();
if (wrapped instanceof SecurityException) {
throw (SecurityException) wrapped;
}
LOGGER.warn("sun.misc.Cleaner#clean() is not accessible. This will impact memory usage.", wrapped);
cleanerMethod = null;
cleanMethod = null;
}
}
public static void clean(final ByteBuffer bb) throws Exception {
if (cleanerMethod != null && cleanMethod != null && bb.isDirect()) {
cleanMethod.invoke(cleanerMethod.invoke(bb));
}
}
}