/*
* 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.tomcat.util.buf;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.res.StringManager;
/*
* This functionality is in a separate class so it is only loaded if cleanDirectBuffer() is called. This is because the
* use of unsafe triggers an unavoidable warning with Java 24.
*/
class ByteBufferUtilsUnsafe {
private static final StringManager sm = StringManager.getManager(ByteBufferUtilsUnsafe.class);
private static final Log log = LogFactory.getLog(ByteBufferUtilsUnsafe.class);
private static final Object unsafe;
private static final Method invokeCleanerMethod;
static {
ByteBuffer tempBuffer = ByteBuffer.allocateDirect(0);
Object unsafeLocal;
Method invokeCleanerMethodLocal;
try {
Class<?> clazz = Class.forName("sun.misc.Unsafe");
Field theUnsafe = clazz.getDeclaredField("theUnsafe");
theUnsafe.setAccessible(true);
unsafeLocal = theUnsafe.get(null);
invokeCleanerMethodLocal = clazz.getMethod("invokeCleaner", ByteBuffer.class);
invokeCleanerMethodLocal.invoke(unsafeLocal, tempBuffer);
} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException | NoSuchMethodException |
SecurityException | ClassNotFoundException | NoSuchFieldException e) {
log.warn(sm.getString("byteBufferUtils.cleaner"), e);
unsafeLocal = null;
invokeCleanerMethodLocal = null;
}
unsafe = unsafeLocal;
invokeCleanerMethod = invokeCleanerMethodLocal;
}
private ByteBufferUtilsUnsafe() {
// Hide the default constructor since this is a utility class.
}
/**
* Clean specified direct buffer. This will cause an unavoidable warning on Java 24 and newer.
*
* @param buf the buffer to clean
*/
static void cleanDirectBuffer(ByteBuffer buf) {
if (invokeCleanerMethod != null) {
try {
invokeCleanerMethod.invoke(unsafe, buf);
} catch (IllegalAccessException | IllegalArgumentException | InvocationTargetException |
SecurityException e) {
if (log.isDebugEnabled()) {
log.debug(sm.getString("byteBufferUtils.cleaner"), e);
}
}
}
}
}