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1 package com.thoughtworks.xstream.converters.reflection;
2
3 import com.thoughtworks.xstream.alias.ClassMapper;
4 import com.thoughtworks.xstream.converters.Converter;
5 import com.thoughtworks.xstream.converters.MarshallingContext;
6 import com.thoughtworks.xstream.converters.UnmarshallingContext;
7 import com.thoughtworks.xstream.io.HierarchicalStreamReader;
8 import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
9
10 import java.util.HashSet  ;
11 import java.util.Set ;
12
13 public class ReflectionConverter implements Converter {
14
15 private ClassMapper classMapper;
16 private String classAttributeIdentifier;
17 private String definedInAttributeIdentifier = "defined-in";
18 private ReflectionProvider reflectionProvider;
19
20 public ReflectionConverter(ClassMapper classMapper, String classAttributeIdentifier, String definedInAttributeIdentifier, ReflectionProvider reflectionProvider) {
21 this.classMapper = classMapper;
22 this.classAttributeIdentifier = classAttributeIdentifier;
23 this.definedInAttributeIdentifier = definedInAttributeIdentifier;
24 this.reflectionProvider = reflectionProvider;
25 }
26
27 public boolean canConvert(Class type) {
28 return true;
29 }
30
31 public void marshal(final Object source, final HierarchicalStreamWriter writer, final MarshallingContext context) {
32 final Set seenFields = new HashSet ();
33 reflectionProvider.visitSerializableFields(source, new ReflectionProvider.Visitor() {
34 public void visit(String fieldName, Class fieldType, Class definedIn, Object newObj) {
35 if (newObj != null) {
36 writer.startNode(classMapper.mapNameToXML(fieldName));
37
38 Class actualType = newObj.getClass();
39
40 Class defaultType = classMapper.lookupDefaultType(fieldType);
41 if (!actualType.equals(defaultType)) {
42 writer.addAttribute(classAttributeIdentifier, classMapper.lookupName(actualType));
43 }
44
45 if (seenFields.contains(fieldName)) {
46 writer.addAttribute(definedInAttributeIdentifier, classMapper.lookupName(definedIn));
47 }
48 context.convertAnother(newObj);
49
50 writer.endNode();
51 seenFields.add(fieldName);
52 }
53 }
54 });
55 }
56
57 public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
58 Object result = context.currentObject();
59
60 if (result == null) {
61 result = reflectionProvider.newInstance(context.getRequiredType());
62 }
63
64 while (reader.hasMoreChildren()) {
65 reader.moveDown();
66
67 String fieldName = classMapper.mapNameFromXML(reader.getNodeName());
68
69 String definedIn = reader.getAttribute(definedInAttributeIdentifier);
70 Class definedInCls = definedIn == null ? null : classMapper.lookupType(definedIn);
71
72 Class type;
73 String classAttribute = reader.getAttribute(classAttributeIdentifier);
74 if (classAttribute == null) {
75 type = classMapper.lookupDefaultType(reflectionProvider.getFieldType(result, fieldName, definedInCls));
76 } else {
77 type = classMapper.lookupType(classAttribute);
78 }
79
80 Object fieldValue = context.convertAnother(result, type);
81
82 reflectionProvider.writeField(result, fieldName, fieldValue, definedInCls);
83
84 reader.moveUp();
85 }
86 return result;
87 }
88
89 }
90 |
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