org.apache.sshd.common.util.closeable.NioChannelDelegateInvocationHandler Maven / Gradle / Ivy
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* 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.sshd.common.util.closeable;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.nio.channels.Channel;
import org.apache.sshd.common.util.GenericUtils;
import org.apache.sshd.common.util.ProxyUtils;
import org.apache.sshd.common.util.logging.LoggingUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Wraps a target instance and a {@link Channel} delegate into a proxy instance that closes both when wrapper
* {@link AutoCloseable#close() close} method called. The {@link Channel#isOpen()} call is invoked only on the delegate
*
* @author Apache MINA SSHD Project
*/
public class NioChannelDelegateInvocationHandler extends AutoCloseableDelegateInvocationHandler {
public NioChannelDelegateInvocationHandler(Object proxyTarget, Channel delegate) {
super(proxyTarget, delegate);
}
public Channel getChannelDelegate() {
return Channel.class.cast(super.getAutoCloseableDelegate());
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
if (!isQueryOpenMethodInvocation(method, args)) {
return super.invoke(proxy, method, args);
}
Channel channelDelegate = getChannelDelegate();
try {
return method.invoke(channelDelegate, args);
} catch (Throwable t) {
Class targetType = channelDelegate.getClass();
Logger log = LoggerFactory.getLogger(targetType);
LoggingUtils.debug(log, "invoke({}#{}) failed ({}) to execute: {}",
targetType.getSimpleName(), method.getName(), t.getClass().getSimpleName(), t.getMessage(), t);
throw ProxyUtils.unwrapInvocationThrowable(t);
}
}
/**
* Wraps a target instance and a {@link Channel} delegate into a proxy instance that closes both when wrapper
* {@link Channel#close() close} method called. The {@link Channel#isOpen()} call is invoked only on the delegate
*
* @param The generic {@link Channel} wrapping interface
* @param proxyTarget The (never {@code null}) target instance - if not {@link AutoCloseable} then it's
* {@code close()} method will not be invoked (i.e., only the delegate)
* @param type The target wrapping interface
* @param delegate The (never {@code null}) delegate to use. Note: the delegate is closed after
* the target instance.
* @return The wrapping proxy
*/
public static T wrapDelegateChannel(
Object proxyTarget, Class type, Channel delegate) {
return ProxyUtils.newProxyInstance(type, new NioChannelDelegateInvocationHandler(proxyTarget, delegate));
}
public static boolean isQueryOpenMethodInvocation(Method m, Object[] args) {
return isQueryOpenMethodInvocation(m) && GenericUtils.isEmpty(args);
}
public static boolean isQueryOpenMethodInvocation(Method m) {
int mods = (m == null) ? 0 : m.getModifiers();
return (m != null)
&& "isOpen".equals(m.getName())
&& Modifier.isPublic(mods)
&& (!Modifier.isStatic(mods))
&& (boolean.class == m.getReturnType())
&& GenericUtils.isEmpty(m.getParameterTypes());
}
}