com.google.inject.internal.InterceptorStackCallback Maven / Gradle / Ivy
/*
* Copyright (C) 2006 Google 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.
*/
package com.google.inject.internal;
import static com.google.inject.internal.BytecodeGen.ENHANCER_BY_GUICE_MARKER;
import com.google.common.collect.Lists;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.util.List;
import java.util.function.BiFunction;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
/**
* Intercepts a method with a stack of interceptors.
*
* Acts as a JDK {@link InvocationHandler} so the proxy using it can avoid Guice-specific types.
*
* @author [email protected] (Bob Lee)
*/
final class InterceptorStackCallback implements InvocationHandler {
private static final String GUICE_INTERNAL_AOP_PACKAGE = "com.google.inject.internal.aop";
final Method method;
final MethodInterceptor[] interceptors;
final BiFunction superInvoker;
public InterceptorStackCallback(
Method method,
List interceptors,
BiFunction superInvoker) {
this.method = method;
this.interceptors = interceptors.toArray(new MethodInterceptor[interceptors.size()]);
this.superInvoker = superInvoker;
}
@Override
public Object invoke(Object proxy, Method unused, Object[] arguments) throws Throwable {
return new InterceptedMethodInvocation(proxy, arguments, 0).proceed();
}
private class InterceptedMethodInvocation implements MethodInvocation {
final Object proxy;
final Object[] arguments;
final int interceptorIndex;
public InterceptedMethodInvocation(Object proxy, Object[] arguments, int interceptorIndex) {
this.proxy = proxy;
this.arguments = arguments;
this.interceptorIndex = interceptorIndex;
}
@Override
public Object proceed() throws Throwable {
try {
return interceptorIndex == interceptors.length
? superInvoker.apply(proxy, arguments)
: interceptors[interceptorIndex].invoke(
new InterceptedMethodInvocation(proxy, arguments, interceptorIndex + 1));
} catch (Throwable t) {
pruneStacktrace(t);
throw t;
}
}
@Override
public Method getMethod() {
return method;
}
@Override
public Object[] getArguments() {
return arguments;
}
@Override
public Object getThis() {
return proxy;
}
@Override
public AccessibleObject getStaticPart() {
return getMethod();
}
}
/**
* Removes stacktrace elements related to AOP internal mechanics from the throwable's stack trace
* and any causes it may have.
*/
private void pruneStacktrace(Throwable throwable) {
for (Throwable t = throwable; t != null; t = t.getCause()) {
StackTraceElement[] stackTrace = t.getStackTrace();
List pruned = Lists.newArrayList();
for (StackTraceElement element : stackTrace) {
String className = element.getClassName();
if (!className.startsWith(InterceptorStackCallback.class.getName())
&& !className.startsWith(GUICE_INTERNAL_AOP_PACKAGE)
&& !className.contains(ENHANCER_BY_GUICE_MARKER)) {
pruned.add(element);
}
}
t.setStackTrace(pruned.toArray(new StackTraceElement[pruned.size()]));
}
}
}