001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.camel.component.bean;
018
019import java.lang.reflect.Proxy;
020
021import org.apache.camel.Endpoint;
022import org.apache.camel.Producer;
023import org.apache.camel.processor.DeferServiceFactory;
024
025/**
026 * A helper class for creating proxies which delegate to Camel
027 *
028 * @version 
029 */
030public final class ProxyHelper {
031
032    /**
033     * Utility classes should not have a public constructor.
034     */
035    private ProxyHelper() {
036    }
037
038    /**
039     * Creates a Proxy which sends the exchange to the endpoint.
040     *
041     * @deprecated use the same method name with binding as parameter
042     */
043    @Deprecated
044    public static <T> T createProxyObject(Endpoint endpoint, Producer producer, ClassLoader classLoader, Class<T>[] interfaces, MethodInfoCache methodCache) {
045        return createProxyObject(endpoint, true, producer, classLoader, interfaces, methodCache);
046    }
047
048    /**
049     * Creates a Proxy which sends the exchange to the endpoint.
050     */
051    @SuppressWarnings("unchecked")
052    public static <T> T createProxyObject(Endpoint endpoint, boolean binding, Producer producer, ClassLoader classLoader, Class<T>[] interfaces, MethodInfoCache methodCache) {
053        return (T) Proxy.newProxyInstance(classLoader, interfaces.clone(), new CamelInvocationHandler(endpoint, binding, producer, methodCache));
054    }
055
056    /**
057     * Creates a Proxy which sends the exchange to the endpoint.
058     *
059     * @deprecated use the same method name with binding as parameter
060     */
061    @Deprecated
062    public static <T> T createProxy(Endpoint endpoint, ClassLoader cl, Class<T> interfaceClass, MethodInfoCache methodCache) throws Exception {
063        return createProxy(endpoint, true, cl, toArray(interfaceClass), methodCache);
064    }
065
066    /**
067     * Creates a Proxy which sends the exchange to the endpoint.
068     */
069    public static <T> T createProxy(Endpoint endpoint, boolean binding, ClassLoader cl, Class<T> interfaceClass, MethodInfoCache methodCache) throws Exception {
070        return createProxy(endpoint, binding, cl, toArray(interfaceClass), methodCache);
071    }
072
073    /**
074     * Creates a Proxy which sends the exchange to the endpoint.
075     *
076     * @deprecated use the same method name with binding as parameter
077     */
078    @Deprecated
079    public static <T> T createProxy(Endpoint endpoint, ClassLoader cl, Class<T>[] interfaceClasses, MethodInfoCache methodCache) throws Exception {
080        return createProxy(endpoint, true, cl, interfaceClasses, methodCache);
081    }
082
083    /**
084     * Creates a Proxy which sends the exchange to the endpoint.
085     */
086    public static <T> T createProxy(Endpoint endpoint, boolean binding, ClassLoader cl, Class<T>[] interfaceClasses, MethodInfoCache methodCache) throws Exception {
087        Producer producer = DeferServiceFactory.createProducer(endpoint);
088        endpoint.getCamelContext().deferStartService(producer, true);
089        return createProxyObject(endpoint, binding, producer, cl, interfaceClasses, methodCache);
090    }
091
092    /**
093     * Creates a Proxy which sends the exchange to the endpoint.
094     */
095    public static <T> T createProxy(Endpoint endpoint, ClassLoader cl, Class<T> interfaceClass) throws Exception {
096        return createProxy(endpoint, true, cl, toArray(interfaceClass));
097    }
098
099    /**
100     * Creates a Proxy which sends the exchange to the endpoint.
101     *
102     * @deprecated use the same method name with binding as parameter
103     */
104    @Deprecated
105    public static <T> T createProxy(Endpoint endpoint, ClassLoader cl, Class<T>... interfaceClasses) throws Exception {
106        return createProxy(endpoint, true, cl, interfaceClasses);
107    }
108
109    /**
110     * Creates a Proxy which sends the exchange to the endpoint.
111     */
112    public static <T> T createProxy(Endpoint endpoint, boolean binding, ClassLoader cl, Class<T>... interfaceClasses) throws Exception {
113        return createProxy(endpoint, binding, cl, interfaceClasses, createMethodInfoCache(endpoint));
114    }
115
116    /**
117     * Creates a Proxy which sends the exchange to the endpoint.
118     */
119    public static <T> T createProxy(Endpoint endpoint, Class<T> interfaceClass) throws Exception {
120        return createProxy(endpoint, true, toArray(interfaceClass));
121    }
122
123    /**
124     * Creates a Proxy which sends the exchange to the endpoint.
125     *
126     * @deprecated use the same method name with binding as parameter
127     */
128    @Deprecated
129    public static <T> T createProxy(Endpoint endpoint, Class<T>... interfaceClasses) throws Exception {
130        return createProxy(endpoint, true, interfaceClasses);
131    }
132
133    /**
134     * Creates a Proxy which sends the exchange to the endpoint.
135     */
136    public static <T> T createProxy(Endpoint endpoint, boolean binding, Class<T>... interfaceClasses) throws Exception {
137        return createProxy(endpoint, binding, getClassLoader(interfaceClasses), interfaceClasses);
138    }
139
140    /**
141     * Creates a Proxy which sends the exchange to the endpoint.
142     */
143    public static <T> T createProxy(Endpoint endpoint, Producer producer, Class<T> interfaceClass) throws Exception {
144        return createProxy(endpoint, true, producer, toArray(interfaceClass));
145    }
146
147    /**
148     * Creates a Proxy which sends the exchange to the endpoint.
149     *
150     * @deprecated use the same method name with binding as parameter
151     */
152    @Deprecated
153    public static <T> T createProxy(Endpoint endpoint, Producer producer, Class<T>... interfaceClasses) throws Exception {
154        return createProxyObject(endpoint, true, producer, getClassLoader(interfaceClasses), interfaceClasses, createMethodInfoCache(endpoint));
155    }
156
157    /**
158     * Creates a Proxy which sends the exchange to the endpoint.
159     */
160    public static <T> T createProxy(Endpoint endpoint, boolean binding, Producer producer, Class<T>... interfaceClasses) throws Exception {
161        return createProxyObject(endpoint, binding, producer, getClassLoader(interfaceClasses), interfaceClasses, createMethodInfoCache(endpoint));
162    }
163
164    /**
165     * Returns the class loader of the first interface or throws {@link IllegalArgumentException} if there are no interfaces specified
166     */
167    protected static ClassLoader getClassLoader(Class<?>... interfaces) {
168        if (interfaces == null || interfaces.length < 1) {
169            throw new IllegalArgumentException("You must provide at least 1 interface class.");
170        }
171        return interfaces[0].getClassLoader();
172    }
173
174    protected static MethodInfoCache createMethodInfoCache(Endpoint endpoint) {
175        return new MethodInfoCache(endpoint.getCamelContext());
176    }
177
178    @SuppressWarnings("unchecked")
179    private static <T> Class<T>[] toArray(Class<T> interfaceClass) {
180        // this method and it's usage is introduced to avoid compiler warnings
181        // about the generic Class arrays in the case we've got only one single
182        // Class to build a Proxy for
183        return new Class[] {interfaceClass};
184    }
185}