Java tutorial
/* * Copyright 2002-2018 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.httpinvoker; import java.io.IOException; import java.io.InputStream; import java.io.ObjectInputStream; import java.io.ObjectOutputStream; import java.io.OutputStream; import com.sun.net.httpserver.HttpExchange; import com.sun.net.httpserver.HttpHandler; import org.springframework.remoting.rmi.RemoteInvocationSerializingExporter; import org.springframework.remoting.support.RemoteInvocation; import org.springframework.remoting.support.RemoteInvocationResult; /** * HTTP request handler that exports the specified service bean as * HTTP invoker service endpoint, accessible via an HTTP invoker proxy. * Designed for Sun's JRE 1.6 HTTP server, implementing the * {@link com.sun.net.httpserver.HttpHandler} interface. * * <p>Deserializes remote invocation objects and serializes remote invocation * result objects. Uses Java serialization just like RMI, but provides the * same ease of setup as Caucho's HTTP-based Hessian protocol. * * <p><b>HTTP invoker is the recommended protocol for Java-to-Java remoting.</b> * It is more powerful and more extensible than Hessian, at the expense of * being tied to Java. Nevertheless, it is as easy to set up as Hessian, * which is its main advantage compared to RMI. * * <p><b>WARNING: Be aware of vulnerabilities due to unsafe Java deserialization: * Manipulated input streams could lead to unwanted code execution on the server * during the deserialization step. As a consequence, do not expose HTTP invoker * endpoints to untrusted clients but rather just between your own services.</b> * In general, we strongly recommend any other message format (e.g. JSON) instead. * * @author Juergen Hoeller * @since 2.5.1 * @see org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor * @see org.springframework.remoting.httpinvoker.HttpInvokerProxyFactoryBean * @deprecated as of Spring Framework 5.1, in favor of {@link HttpInvokerServiceExporter} */ @Deprecated @org.springframework.lang.UsesSunHttpServer public class SimpleHttpInvokerServiceExporter extends RemoteInvocationSerializingExporter implements HttpHandler { /** * Reads a remote invocation from the request, executes it, * and writes the remote invocation result to the response. * @see #readRemoteInvocation(HttpExchange) * @see #invokeAndCreateResult(RemoteInvocation, Object) * @see #writeRemoteInvocationResult(HttpExchange, RemoteInvocationResult) */ @Override public void handle(HttpExchange exchange) throws IOException { try { RemoteInvocation invocation = readRemoteInvocation(exchange); RemoteInvocationResult result = invokeAndCreateResult(invocation, getProxy()); writeRemoteInvocationResult(exchange, result); exchange.close(); } catch (ClassNotFoundException ex) { exchange.sendResponseHeaders(500, -1); logger.error("Class not found during deserialization", ex); } } /** * Read a RemoteInvocation from the given HTTP request. * <p>Delegates to {@link #readRemoteInvocation(HttpExchange, InputStream)} * with the {@link HttpExchange#getRequestBody()} request's input stream}. * @param exchange current HTTP request/response * @return the RemoteInvocation object * @throws java.io.IOException in case of I/O failure * @throws ClassNotFoundException if thrown by deserialization */ protected RemoteInvocation readRemoteInvocation(HttpExchange exchange) throws IOException, ClassNotFoundException { return readRemoteInvocation(exchange, exchange.getRequestBody()); } /** * Deserialize a RemoteInvocation object from the given InputStream. * <p>Gives {@link #decorateInputStream} a chance to decorate the stream * first (for example, for custom encryption or compression). Creates a * {@link org.springframework.remoting.rmi.CodebaseAwareObjectInputStream} * and calls {@link #doReadRemoteInvocation} to actually read the object. * <p>Can be overridden for custom serialization of the invocation. * @param exchange current HTTP request/response * @param is the InputStream to read from * @return the RemoteInvocation object * @throws java.io.IOException in case of I/O failure * @throws ClassNotFoundException if thrown during deserialization */ protected RemoteInvocation readRemoteInvocation(HttpExchange exchange, InputStream is) throws IOException, ClassNotFoundException { ObjectInputStream ois = createObjectInputStream(decorateInputStream(exchange, is)); return doReadRemoteInvocation(ois); } /** * Return the InputStream to use for reading remote invocations, * potentially decorating the given original InputStream. * <p>The default implementation returns the given stream as-is. * Can be overridden, for example, for custom encryption or compression. * @param exchange current HTTP request/response * @param is the original InputStream * @return the potentially decorated InputStream * @throws java.io.IOException in case of I/O failure */ protected InputStream decorateInputStream(HttpExchange exchange, InputStream is) throws IOException { return is; } /** * Write the given RemoteInvocationResult to the given HTTP response. * @param exchange current HTTP request/response * @param result the RemoteInvocationResult object * @throws java.io.IOException in case of I/O failure */ protected void writeRemoteInvocationResult(HttpExchange exchange, RemoteInvocationResult result) throws IOException { exchange.getResponseHeaders().set("Content-Type", getContentType()); exchange.sendResponseHeaders(200, 0); writeRemoteInvocationResult(exchange, result, exchange.getResponseBody()); } /** * Serialize the given RemoteInvocation to the given OutputStream. * <p>The default implementation gives {@link #decorateOutputStream} a chance * to decorate the stream first (for example, for custom encryption or compression). * Creates an {@link java.io.ObjectOutputStream} for the final stream and calls * {@link #doWriteRemoteInvocationResult} to actually write the object. * <p>Can be overridden for custom serialization of the invocation. * @param exchange current HTTP request/response * @param result the RemoteInvocationResult object * @param os the OutputStream to write to * @throws java.io.IOException in case of I/O failure * @see #decorateOutputStream * @see #doWriteRemoteInvocationResult */ protected void writeRemoteInvocationResult(HttpExchange exchange, RemoteInvocationResult result, OutputStream os) throws IOException { ObjectOutputStream oos = createObjectOutputStream(decorateOutputStream(exchange, os)); doWriteRemoteInvocationResult(result, oos); oos.flush(); } /** * Return the OutputStream to use for writing remote invocation results, * potentially decorating the given original OutputStream. * <p>The default implementation returns the given stream as-is. * Can be overridden, for example, for custom encryption or compression. * @param exchange current HTTP request/response * @param os the original OutputStream * @return the potentially decorated OutputStream * @throws java.io.IOException in case of I/O failure */ protected OutputStream decorateOutputStream(HttpExchange exchange, OutputStream os) throws IOException { return os; } }