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1 package com.thoughtworks.xstream.converters.extended;
2
3 import com.thoughtworks.xstream.alias.ClassMapper;
4 import com.thoughtworks.xstream.converters.ConversionException;
5 import com.thoughtworks.xstream.converters.Converter;
6 import com.thoughtworks.xstream.converters.MarshallingContext;
7 import com.thoughtworks.xstream.converters.UnmarshallingContext;
8 import com.thoughtworks.xstream.io.HierarchicalStreamReader;
9 import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
10
11 import java.lang.reflect.InvocationHandler  ;
12 import java.lang.reflect.Proxy ;
13 import java.util.ArrayList ;
14 import java.util.List ;
15
16
22 public class DynamicProxyConverter implements Converter {
23
24 private ClassLoader classLoader;
25 private ClassMapper classMapper;
26
27 public DynamicProxyConverter(ClassMapper classMapper) {
28 this(classMapper, DynamicProxyConverter.class.getClassLoader());
29 }
30
31 public DynamicProxyConverter(ClassMapper classMapper, ClassLoader classLoader) {
32 this.classLoader = classLoader;
33 this.classMapper = classMapper;
34 }
35
36 public boolean canConvert(Class type) {
37 return type.equals(ClassMapper.DynamicProxy.class) || Proxy.isProxyClass(type);
38 }
39
40 public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
41 InvocationHandler invocationHandler = Proxy.getInvocationHandler(source);
42 addInterfacesToXml(source, writer);
43 writer.startNode("handler");
44 writer.addAttribute("class", classMapper.lookupName(invocationHandler.getClass()));
45 context.convertAnother(invocationHandler);
46 writer.endNode();
47 }
48
49 private void addInterfacesToXml(Object source, HierarchicalStreamWriter writer) {
50 Class [] interfaces = source.getClass().getInterfaces();
51 for (int i = 0; i < interfaces.length; i++) {
52 Class currentInterface = interfaces[i];
53 writer.startNode("interface");
54 writer.setValue(classMapper.lookupName(currentInterface));
55 writer.endNode();
56 }
57 }
58
59 public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
60 List interfaces = new ArrayList ();
61 InvocationHandler handler = null;
62 while (reader.hasMoreChildren()) {
63 reader.moveDown();
64 String elementName = reader.getNodeName();
65 if (elementName.equals("interface")) {
66 interfaces.add(classMapper.lookupType(reader.getValue()));
67 } else if (elementName.equals("handler")) {
68 Class handlerType = classMapper.lookupType(reader.getAttribute("class"));
69 handler = (InvocationHandler ) context.convertAnother(null, handlerType);
70 }
71 reader.moveUp();
72 }
73 if (handler == null) {
74 throw new ConversionException("No InvocationHandler specified for dynamic proxy");
75 }
76 Class [] interfacesAsArray = new Class [interfaces.size()];
77 interfaces.toArray(interfacesAsArray);
78 return Proxy.newProxyInstance(classLoader, interfacesAsArray, handler);
79 }
80 }
81 |
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