ca.uhn.fhir.util.ProxyUtil Maven / Gradle / Ivy
/*-
* #%L
* HAPI FHIR - Core Library
* %%
* Copyright (C) 2014 - 2024 Smile CDR, Inc.
* %%
* 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.
* #L%
*/
package ca.uhn.fhir.util;
import org.apache.commons.lang3.Validate;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
public class ProxyUtil {
private ProxyUtil() {}
/**
* Wrap theInstance in a Proxy that synchronizes every method.
*
* @param theClass the target interface
* @param theInstance the instance to wrap
* @return a Proxy implementing theClass interface that syncronizes every call on theInstance
* @param the interface type
*/
public static T synchronizedProxy(Class theClass, T theInstance) {
Validate.isTrue(theClass.isInterface(), "%s is not an interface", theClass);
InvocationHandler handler = new SynchronizedHandler(theInstance);
Object object = Proxy.newProxyInstance(theClass.getClassLoader(), new Class[] {theClass}, handler);
return theClass.cast(object);
}
/**
* Simple handler that first synchronizes on the delegate
*/
static class SynchronizedHandler implements InvocationHandler {
private final Object theDelegate;
SynchronizedHandler(Object theDelegate) {
this.theDelegate = theDelegate;
}
@Override
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
synchronized (theDelegate) {
return method.invoke(theDelegate, args);
}
}
}
}