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16 package net.sf.cglib.transform.impl;
17
18 import net.sf.cglib.transform.*;
19 import java.util.*;
20 import net.sf.cglib.core.*;
21 import org.objectweb.asm.Attribute;
22 import org.objectweb.asm.Label;
23 import org.objectweb.asm.Type;
24
25 public class FieldProviderTransformer extends ClassEmitterTransformer {
26
27 private static final String  FIELD_NAMES = "CGLIB$FIELD_NAMES";
28 private static final String FIELD_TYPES = "CGLIB$FIELD_TYPES";
29
30 private static final Type FIELD_PROVIDER =
31 TypeUtils.parseType("net.sf.cglib.transform.impl.FieldProvider");
32 private static final Type ILLEGAL_ARGUMENT_EXCEPTION =
33 TypeUtils.parseType("IllegalArgumentException");
34 private static final Signature PROVIDER_GET =
35 TypeUtils.parseSignature("Object getField(String)");
36 private static final Signature PROVIDER_SET =
37 TypeUtils.parseSignature("void setField(String, Object)");
38 private static final Signature PROVIDER_SET_BY_INDEX =
39 TypeUtils.parseSignature("void setField(int, Object)");
40 private static final Signature PROVIDER_GET_BY_INDEX =
41 TypeUtils.parseSignature("Object getField(int)");
42 private static final Signature PROVIDER_GET_TYPES =
43 TypeUtils.parseSignature("Class[] getFieldTypes()");
44 private static final Signature PROVIDER_GET_NAMES =
45 TypeUtils.parseSignature("String[] getFieldNames()");
46
47 private int access;
48 private Map fields;
49
50 public void begin_class(int version, int access, String className, Type superType, Type[] interfaces, String sourceFile) {
51 if (!TypeUtils.isAbstract(access)) {
52 interfaces = TypeUtils.add(interfaces, FIELD_PROVIDER);
53 }
54 this.access = access;
55 fields = new HashMap();
56 super.begin_class(version, access, className, superType, interfaces, sourceFile);
57 }
58
59 public void declare_field(int access, String name, Type type, Object value) {
60 super.declare_field(access, name, type, value);
61
62 if (!TypeUtils.isStatic(access)) {
63 fields.put(name, type);
64 }
65 }
66
67 public void end_class() {
68 if (!TypeUtils.isInterface(access)) {
69 try {
70 generate();
71 } catch (RuntimeException e) {
72 throw e;
73 } catch (Exception e) {
74 throw new CodeGenerationException(e);
75 }
76 }
77 super.end_class();
78 }
79
80 private void generate() throws Exception {
81 final String [] names = (String [])fields.keySet().toArray(new String [fields.size()]);
82
83 int indexes[] = new int[names.length];
84 for (int i = 0; i < indexes.length; i++) {
85 indexes[i] = i;
86 }
87
88 super.declare_field(Constants.PRIVATE_FINAL_STATIC, FIELD_NAMES, Constants.TYPE_STRING_ARRAY, null);
89 super.declare_field(Constants.PRIVATE_FINAL_STATIC, FIELD_TYPES, Constants.TYPE_CLASS_ARRAY, null);
90
91 initFieldProvider(names);
93 getNames();
94 getTypes();
95 getField(names);
96 setField(names);
97 setByIndex(names, indexes);
98 getByIndex(names, indexes);
99 }
100
101 private void initFieldProvider(String [] names) {
102 CodeEmitter e = getStaticHook();
103 EmitUtils.push_object(e, names);
104 e.putstatic(getClassType(), FIELD_NAMES, Constants.TYPE_STRING_ARRAY);
105
106 e.push(names.length);
107 e.newarray(Constants.TYPE_CLASS);
108 e.dup();
109 for(int i = 0; i < names.length; i++ ){
110 e.dup();
111 e.push(i);
112 Type type = (Type)fields.get(names[i]);
113 EmitUtils.load_class(e, type);
114 e.aastore();
115 }
116 e.putstatic(getClassType(), FIELD_TYPES, Constants.TYPE_CLASS_ARRAY);
117 }
118
119 private void getNames() {
120 CodeEmitter e = super.begin_method(Constants.ACC_PUBLIC, PROVIDER_GET_NAMES, null);
121 e.getstatic(getClassType(), FIELD_NAMES, Constants.TYPE_STRING_ARRAY);
122 e.return_value();
123 e.end_method();
124 }
125
126 private void getTypes() {
127 CodeEmitter e = super.begin_method(Constants.ACC_PUBLIC, PROVIDER_GET_TYPES, null);
128 e.getstatic(getClassType(), FIELD_TYPES, Constants.TYPE_CLASS_ARRAY);
129 e.return_value();
130 e.end_method();
131 }
132
133 private void setByIndex(final String [] names, final int[] indexes) throws Exception {
134 final CodeEmitter e = super.begin_method(Constants.ACC_PUBLIC, PROVIDER_SET_BY_INDEX, null);
135 e.load_this();
136 e.load_arg(1);
137 e.load_arg(0);
138 e.process_switch(indexes, new ProcessSwitchCallback() {
139 public void processCase(int key, Label end) throws Exception {
140 Type type = (Type)fields.get(names[key]);
141 e.unbox(type);
142 e.putfield(names[key]);
143 e.return_value();
144 }
145 public void processDefault() throws Exception {
146 e.throw_exception(ILLEGAL_ARGUMENT_EXCEPTION, "Unknown field index");
147 }
148 });
149 e.end_method();
150 }
151
152 private void getByIndex(final String [] names, final int[] indexes) throws Exception {
153 final CodeEmitter e = super.begin_method(Constants.ACC_PUBLIC, PROVIDER_GET_BY_INDEX, null);
154 e.load_this();
155 e.load_arg(0);
156 e.process_switch(indexes, new ProcessSwitchCallback() {
157 public void processCase(int key, Label end) throws Exception {
158 Type type = (Type)fields.get(names[key]);
159 e.getfield(names[key]);
160 e.box(type);
161 e.return_value();
162 }
163 public void processDefault() throws Exception {
164 e.throw_exception(ILLEGAL_ARGUMENT_EXCEPTION, "Unknown field index");
165 }
166 });
167 e.end_method();
168 }
169
170 private void getField(String [] names) throws Exception {
173 final CodeEmitter e = begin_method(Constants.ACC_PUBLIC, PROVIDER_GET, null);
174 e.load_this();
175 e.load_arg(0);
176 EmitUtils.string_switch(e, names, Constants.SWITCH_STYLE_HASH, new ObjectSwitchCallback() {
177 public void processCase(Object key, Label end) {
178 Type type = (Type)fields.get(key);
179 e.getfield((String )key);
180 e.box(type);
181 e.return_value();
182 }
183 public void processDefault() {
184 e.throw_exception(ILLEGAL_ARGUMENT_EXCEPTION, "Unknown field name");
185 }
186 });
187 e.end_method();
188 }
189
190 private void setField(String [] names) throws Exception {
191 final CodeEmitter e = begin_method(Constants.ACC_PUBLIC, PROVIDER_SET, null);
192 e.load_this();
193 e.load_arg(1);
194 e.load_arg(0);
195 EmitUtils.string_switch(e, names, Constants.SWITCH_STYLE_HASH, new ObjectSwitchCallback() {
196 public void processCase(Object key, Label end) {
197 Type type = (Type)fields.get(key);
198 e.unbox(type);
199 e.putfield((String )key);
200 e.return_value();
201 }
202 public void processDefault() {
203 e.throw_exception(ILLEGAL_ARGUMENT_EXCEPTION, "Unknown field name");
204 }
205 });
206 e.end_method();
207 }
208 }
209 |
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