org.springframework.remoting.rmi.CodebaseAwareObjectInputStream Maven / Gradle / Ivy
/*
* Copyright 2002-2007 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
*
* 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 org.springframework.remoting.rmi;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectStreamClass;
import java.lang.reflect.Proxy;
import java.rmi.server.RMIClassLoader;
import org.springframework.util.ClassUtils;
/**
* Special ObjectInputStream subclass that falls back to a specified codebase
* to load classes from if not found locally. In contrast to standard RMI
* conventions for dynamic class download, it is the client that determines
* the codebase URL here, rather than the "java.rmi.server.codebase" system
* property on the server.
*
* Uses the JDK's RMIClassLoader to load classes from the specified codebase.
* The codebase can consist of multiple URLs, separated by spaces.
* Note that RMIClassLoader requires a SecurityManager to be set, like when
* using dynamic class download with standard RMI! (See the RMI documentation
* for details.)
*
*
Despite residing in the RMI package, this class is not used for
* RmiClientInterceptor, which uses the standard RMI infrastructure instead
* and thus is only able to rely on RMI's standard dynamic class download via
* "java.rmi.server.codebase". CodebaseAwareObjectInputStream is used by
* HttpInvokerClientInterceptor (see the "codebaseUrl" property there).
*
*
Thanks to Lionel Mestre for suggesting the option and providing
* a prototype!
*
* @author Juergen Hoeller
* @since 1.1.3
* @see java.rmi.server.RMIClassLoader
* @see org.springframework.remoting.httpinvoker.HttpInvokerClientInterceptor#setCodebaseUrl
*/
public class CodebaseAwareObjectInputStream extends ObjectInputStream {
private final ClassLoader classLoader;
private final String codebaseUrl;
/**
* Create a new CodebaseAwareObjectInputStream for the given InputStream and codebase.
* @param in the InputStream to read from
* @param codebaseUrl the codebase URL to load classes from if not found locally
* (can consist of multiple URLs, separated by spaces)
* @see java.io.ObjectInputStream#ObjectInputStream(java.io.InputStream)
*/
public CodebaseAwareObjectInputStream(InputStream in, String codebaseUrl) throws IOException {
this(in, null, codebaseUrl);
}
/**
* Create a new CodebaseAwareObjectInputStream for the given InputStream and codebase.
* @param in the InputStream to read from
* @param classLoader the ClassLoader to use for loading local classes
* (may be null to indicate RMI's default ClassLoader)
* @param codebaseUrl the codebase URL to load classes from if not found locally
* (can consist of multiple URLs, separated by spaces)
* @see java.io.ObjectInputStream#ObjectInputStream(java.io.InputStream)
*/
public CodebaseAwareObjectInputStream(
InputStream in, ClassLoader classLoader, String codebaseUrl) throws IOException {
super(in);
this.classLoader = classLoader;
this.codebaseUrl = codebaseUrl;
}
/**
* Overridden version delegates to super class first,
* falling back to the specified codebase if not found locally.
*/
protected Class resolveClass(ObjectStreamClass classDesc) throws IOException, ClassNotFoundException {
try {
if (this.classLoader != null) {
// Use the specified ClassLoader to resolve local classes.
return Class.forName(classDesc.getName(), false, this.classLoader);
}
else {
// Let RMI use it's default ClassLoader...
return super.resolveClass(classDesc);
}
}
catch (ClassNotFoundException ex) {
// Explicitly resolve primitive class name.
// This will be done by the standard ObjectInputStream on JDK 1.4+,
// but needs to be done explicitly on JDK 1.3.
Class clazz = ClassUtils.resolvePrimitiveClassName(classDesc.getName());
if (clazz != null) {
return clazz;
}
// If codebaseUrl is set, try to load the class with the RMIClassLoader.
// Else, propagate the ClassNotFoundException.
if (this.codebaseUrl == null) {
throw ex;
}
return RMIClassLoader.loadClass(this.codebaseUrl, classDesc.getName());
}
}
/**
* Overridden version delegates to super class first,
* falling back to the specified codebase if not found locally.
*/
protected Class resolveProxyClass(String[] interfaces) throws IOException, ClassNotFoundException {
if (this.classLoader != null) {
// Use the specified ClassLoader to resolve local proxy classes.
Class[] resolvedInterfaces = new Class[interfaces.length];
for (int i = 0; i < interfaces.length; i++) {
try {
resolvedInterfaces[i] = Class.forName(interfaces[i], false, this.classLoader);
}
catch (ClassNotFoundException ex) {
if (this.codebaseUrl == null) {
throw ex;
}
resolvedInterfaces[i] = RMIClassLoader.loadClass(this.codebaseUrl, interfaces[i]);
}
}
try {
return Proxy.getProxyClass(this.classLoader, resolvedInterfaces);
}
catch (IllegalArgumentException ex) {
throw new ClassNotFoundException(null, ex);
}
}
else {
// Let RMI use it's default ClassLoader...
try {
return super.resolveProxyClass(interfaces);
}
catch (ClassNotFoundException ex) {
if (this.codebaseUrl == null) {
throw ex;
}
ClassLoader loader = RMIClassLoader.getClassLoader(this.codebaseUrl);
Class[] resolvedInterfaces = new Class[interfaces.length];
for (int i = 0; i < interfaces.length; i++) {
resolvedInterfaces[i] = loader.loadClass(interfaces[i]);
}
return Proxy.getProxyClass(loader, resolvedInterfaces);
}
}
}
}