Java tutorial
/* * Copyright 2002-2017 the original author or authors. * * 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 * * https://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.springframework.remoting.caucho; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.UndeclaredThrowableException; import java.net.ConnectException; import java.net.MalformedURLException; import com.caucho.hessian.HessianException; import com.caucho.hessian.client.HessianConnectionException; import com.caucho.hessian.client.HessianConnectionFactory; import com.caucho.hessian.client.HessianProxyFactory; import com.caucho.hessian.client.HessianRuntimeException; import com.caucho.hessian.io.SerializerFactory; import org.aopalliance.intercept.MethodInterceptor; import org.aopalliance.intercept.MethodInvocation; import org.springframework.lang.Nullable; import org.springframework.remoting.RemoteAccessException; import org.springframework.remoting.RemoteConnectFailureException; import org.springframework.remoting.RemoteLookupFailureException; import org.springframework.remoting.RemoteProxyFailureException; import org.springframework.remoting.support.UrlBasedRemoteAccessor; import org.springframework.util.Assert; /** * {@link org.aopalliance.intercept.MethodInterceptor} for accessing a Hessian service. * Supports authentication via username and password. * The service URL must be an HTTP URL exposing a Hessian service. * * <p>Hessian is a slim, binary RPC protocol. * For information on Hessian, see the * <a href="http://hessian.caucho.com">Hessian website</a> * <b>Note: As of Spring 4.0, this client requires Hessian 4.0 or above.</b> * * <p>Note: There is no requirement for services accessed with this proxy factory * to have been exported using Spring's {@link HessianServiceExporter}, as there is * no special handling involved. As a consequence, you can also access services that * have been exported using Caucho's {@link com.caucho.hessian.server.HessianServlet}. * * @author Juergen Hoeller * @since 29.09.2003 * @see #setServiceInterface * @see #setServiceUrl * @see #setUsername * @see #setPassword * @see HessianServiceExporter * @see HessianProxyFactoryBean * @see com.caucho.hessian.client.HessianProxyFactory * @see com.caucho.hessian.server.HessianServlet */ public class HessianClientInterceptor extends UrlBasedRemoteAccessor implements MethodInterceptor { private HessianProxyFactory proxyFactory = new HessianProxyFactory(); @Nullable private Object hessianProxy; /** * Set the HessianProxyFactory instance to use. * If not specified, a default HessianProxyFactory will be created. * <p>Allows to use an externally configured factory instance, * in particular a custom HessianProxyFactory subclass. */ public void setProxyFactory(@Nullable HessianProxyFactory proxyFactory) { this.proxyFactory = (proxyFactory != null ? proxyFactory : new HessianProxyFactory()); } /** * Specify the Hessian SerializerFactory to use. * <p>This will typically be passed in as an inner bean definition * of type {@code com.caucho.hessian.io.SerializerFactory}, * with custom bean property values applied. */ public void setSerializerFactory(SerializerFactory serializerFactory) { this.proxyFactory.setSerializerFactory(serializerFactory); } /** * Set whether to send the Java collection type for each serialized * collection. Default is "true". */ public void setSendCollectionType(boolean sendCollectionType) { this.proxyFactory.getSerializerFactory().setSendCollectionType(sendCollectionType); } /** * Set whether to allow non-serializable types as Hessian arguments * and return values. Default is "true". */ public void setAllowNonSerializable(boolean allowNonSerializable) { this.proxyFactory.getSerializerFactory().setAllowNonSerializable(allowNonSerializable); } /** * Set whether overloaded methods should be enabled for remote invocations. * Default is "false". * @see com.caucho.hessian.client.HessianProxyFactory#setOverloadEnabled */ public void setOverloadEnabled(boolean overloadEnabled) { this.proxyFactory.setOverloadEnabled(overloadEnabled); } /** * Set the username that this factory should use to access the remote service. * Default is none. * <p>The username will be sent by Hessian via HTTP Basic Authentication. * @see com.caucho.hessian.client.HessianProxyFactory#setUser */ public void setUsername(String username) { this.proxyFactory.setUser(username); } /** * Set the password that this factory should use to access the remote service. * Default is none. * <p>The password will be sent by Hessian via HTTP Basic Authentication. * @see com.caucho.hessian.client.HessianProxyFactory#setPassword */ public void setPassword(String password) { this.proxyFactory.setPassword(password); } /** * Set whether Hessian's debug mode should be enabled. * Default is "false". * @see com.caucho.hessian.client.HessianProxyFactory#setDebug */ public void setDebug(boolean debug) { this.proxyFactory.setDebug(debug); } /** * Set whether to use a chunked post for sending a Hessian request. * @see com.caucho.hessian.client.HessianProxyFactory#setChunkedPost */ public void setChunkedPost(boolean chunkedPost) { this.proxyFactory.setChunkedPost(chunkedPost); } /** * Specify a custom HessianConnectionFactory to use for the Hessian client. */ public void setConnectionFactory(HessianConnectionFactory connectionFactory) { this.proxyFactory.setConnectionFactory(connectionFactory); } /** * Set the socket connect timeout to use for the Hessian client. * @see com.caucho.hessian.client.HessianProxyFactory#setConnectTimeout */ public void setConnectTimeout(long timeout) { this.proxyFactory.setConnectTimeout(timeout); } /** * Set the timeout to use when waiting for a reply from the Hessian service. * @see com.caucho.hessian.client.HessianProxyFactory#setReadTimeout */ public void setReadTimeout(long timeout) { this.proxyFactory.setReadTimeout(timeout); } /** * Set whether version 2 of the Hessian protocol should be used for * parsing requests and replies. Default is "false". * @see com.caucho.hessian.client.HessianProxyFactory#setHessian2Request */ public void setHessian2(boolean hessian2) { this.proxyFactory.setHessian2Request(hessian2); this.proxyFactory.setHessian2Reply(hessian2); } /** * Set whether version 2 of the Hessian protocol should be used for * parsing requests. Default is "false". * @see com.caucho.hessian.client.HessianProxyFactory#setHessian2Request */ public void setHessian2Request(boolean hessian2) { this.proxyFactory.setHessian2Request(hessian2); } /** * Set whether version 2 of the Hessian protocol should be used for * parsing replies. Default is "false". * @see com.caucho.hessian.client.HessianProxyFactory#setHessian2Reply */ public void setHessian2Reply(boolean hessian2) { this.proxyFactory.setHessian2Reply(hessian2); } @Override public void afterPropertiesSet() { super.afterPropertiesSet(); prepare(); } /** * Initialize the Hessian proxy for this interceptor. * @throws RemoteLookupFailureException if the service URL is invalid */ public void prepare() throws RemoteLookupFailureException { try { this.hessianProxy = createHessianProxy(this.proxyFactory); } catch (MalformedURLException ex) { throw new RemoteLookupFailureException("Service URL [" + getServiceUrl() + "] is invalid", ex); } } /** * Create the Hessian proxy that is wrapped by this interceptor. * @param proxyFactory the proxy factory to use * @return the Hessian proxy * @throws MalformedURLException if thrown by the proxy factory * @see com.caucho.hessian.client.HessianProxyFactory#create */ protected Object createHessianProxy(HessianProxyFactory proxyFactory) throws MalformedURLException { Assert.notNull(getServiceInterface(), "'serviceInterface' is required"); return proxyFactory.create(getServiceInterface(), getServiceUrl(), getBeanClassLoader()); } @Override @Nullable public Object invoke(MethodInvocation invocation) throws Throwable { if (this.hessianProxy == null) { throw new IllegalStateException("HessianClientInterceptor is not properly initialized - " + "invoke 'prepare' before attempting any operations"); } ClassLoader originalClassLoader = overrideThreadContextClassLoader(); try { return invocation.getMethod().invoke(this.hessianProxy, invocation.getArguments()); } catch (InvocationTargetException ex) { Throwable targetEx = ex.getTargetException(); // Hessian 4.0 check: another layer of InvocationTargetException. if (targetEx instanceof InvocationTargetException) { targetEx = ((InvocationTargetException) targetEx).getTargetException(); } if (targetEx instanceof HessianConnectionException) { throw convertHessianAccessException(targetEx); } else if (targetEx instanceof HessianException || targetEx instanceof HessianRuntimeException) { Throwable cause = targetEx.getCause(); throw convertHessianAccessException(cause != null ? cause : targetEx); } else if (targetEx instanceof UndeclaredThrowableException) { UndeclaredThrowableException utex = (UndeclaredThrowableException) targetEx; throw convertHessianAccessException(utex.getUndeclaredThrowable()); } else { throw targetEx; } } catch (Throwable ex) { throw new RemoteProxyFailureException( "Failed to invoke Hessian proxy for remote service [" + getServiceUrl() + "]", ex); } finally { resetThreadContextClassLoader(originalClassLoader); } } /** * Convert the given Hessian access exception to an appropriate * Spring RemoteAccessException. * @param ex the exception to convert * @return the RemoteAccessException to throw */ protected RemoteAccessException convertHessianAccessException(Throwable ex) { if (ex instanceof HessianConnectionException || ex instanceof ConnectException) { return new RemoteConnectFailureException( "Cannot connect to Hessian remote service at [" + getServiceUrl() + "]", ex); } else { return new RemoteAccessException("Cannot access Hessian remote service at [" + getServiceUrl() + "]", ex); } } }