// 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

// 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.cloud.utils.db;

import java.lang.reflect.AnnotatedElement;

import java.lang.reflect.Method;

import net.sf.cglib.proxy.Callback;

import net.sf.cglib.proxy.MethodInterceptor;

import net.sf.cglib.proxy.MethodProxy;

import com.cloud.utils.component.AnnotationInterceptor;

public class DatabaseCallback implements MethodInterceptor, AnnotationInterceptor<Transaction> {

@Override

public Object intercept(Object object, Method method, Object[] args, MethodProxy methodProxy) throws Throwable {

Transaction txn = interceptStart(method);

try {

return methodProxy.invokeSuper(object, args);

} finally {

interceptComplete(method, txn);

}

}

@Override

public boolean needToIntercept(AnnotatedElement element) {

if (!(element instanceof Method)) {

return false;

}

Method method = (Method)element;

DB db = method.getAnnotation(DB.class);

if (db != null) {

return db.txn();

}

Class<?> clazz = method.getDeclaringClass();

do {

db = clazz.getAnnotation(DB.class);

if (db != null) {

return db.txn();

}

clazz = clazz.getSuperclass();

} while (clazz != Object.class && clazz != null);

return false;

}

@Override

public Transaction interceptStart(AnnotatedElement element) {

return Transaction.open(((Method)element).getName());

}

@Override

public void interceptComplete(AnnotatedElement element, Transaction txn) {

txn.close();

}

@Override

public void interceptException(AnnotatedElement element, Transaction txn) {

txn.close();

}

@Override

public Callback getCallback() {

return this;

}

}