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1
16
17 package net.sf.cglib.core;
18
19 import java.lang.reflect.Method  ;
20 import org.objectweb.asm.ClassVisitor;
21 import org.objectweb.asm.Label;
22 import org.objectweb.asm.Type;
23
24
53 abstract public class KeyFactory {
54 private static final Signature GET_NAME =
55 TypeUtils.parseSignature("String getName()");
56 private static final Signature GET_CLASS =
57 TypeUtils.parseSignature("Class getClass()");
58 private static final Signature HASH_CODE =
59 TypeUtils.parseSignature("int hashCode()");
60 private static final Signature EQUALS =
61 TypeUtils.parseSignature("boolean equals(Object)");
62 private static final Signature TO_STRING =
63 TypeUtils.parseSignature("String toString()");
64 private static final Signature APPEND_STRING =
65 TypeUtils.parseSignature("StringBuffer append(String)");
66 private static final Type KEY_FACTORY =
67 TypeUtils.parseType("net.sf.cglib.core.KeyFactory");
68
69 private final static int PRIMES[] = {
71 11, 73, 179, 331,
72 521, 787, 1213, 1823,
73 2609, 3691, 5189, 7247,
74 10037, 13931, 19289, 26627,
75 36683, 50441, 69403, 95401,
76 131129, 180179, 247501, 340057,
77 467063, 641371, 880603, 1209107,
78 1660097, 2279161, 3129011, 4295723,
79 5897291, 8095873, 11114263, 15257791,
80 20946017, 28754629, 39474179, 54189869,
81 74391461, 102123817, 140194277, 192456917,
82 264202273, 362693231, 497900099, 683510293,
83 938313161, 1288102441, 1768288259 };
84
85
86 public static final Customizer CLASS_BY_NAME = new Customizer() {
87 public void customize(CodeEmitter e, Type type) {
88 if (type.equals(Constants.TYPE_CLASS)) {
89 e.invoke_virtual(Constants.TYPE_CLASS, GET_NAME);
90 }
91 }
92 };
93
94 public static final Customizer OBJECT_BY_CLASS = new Customizer() {
95 public void customize(CodeEmitter e, Type type) {
96 e.invoke_virtual(Constants.TYPE_OBJECT, GET_CLASS);
97 }
98 };
99
100 protected KeyFactory() {
101 }
102
103 public static KeyFactory create(Class keyInterface) {
104 return create(keyInterface, null);
105 }
106
107 public static KeyFactory create(Class keyInterface, Customizer customizer) {
108 return create(keyInterface.getClassLoader(), keyInterface, customizer);
109 }
110
111 public static KeyFactory create(ClassLoader loader, Class keyInterface, Customizer customizer) {
112 Generator gen = new Generator();
113 gen.setInterface(keyInterface);
114 gen.setCustomizer(customizer);
115 gen.setClassLoader(loader);
116 return gen.create();
117 }
118
119 public static class Generator extends AbstractClassGenerator {
120 private static final Source SOURCE = new Source(KeyFactory.class.getName());
121 private Class keyInterface;
122 private Customizer customizer;
123 private int constant;
124 private int multiplier;
125
126 public Generator() {
127 super(SOURCE);
128 }
129
130 protected ClassLoader getDefaultClassLoader() {
131 return keyInterface.getClassLoader();
132 }
133
134 public void setCustomizer(Customizer customizer) {
135 this.customizer = customizer;
136 }
137
138 public void setInterface(Class keyInterface) {
139 this.keyInterface = keyInterface;
140 }
141
142 public KeyFactory create() {
143 setNamePrefix(keyInterface.getName());
144 return (KeyFactory)super.create(keyInterface.getName());
145 }
146
147 public void setHashConstant(int constant) {
148 this.constant = constant;
149 }
150
151 public void setHashMultiplier(int multiplier) {
152 this.multiplier = multiplier;
153 }
154
155 protected Object firstInstance(Class type) {
156 return ReflectUtils.newInstance(type);
157 }
158
159 protected Object nextInstance(Object instance) {
160 return instance;
161 }
162
163 public void generateClass(ClassVisitor v) {
164 ClassEmitter ce = new ClassEmitter(v);
165
166 Method newInstance = ReflectUtils.findNewInstance(keyInterface);
167 if (!newInstance.getReturnType().equals(Object .class)) {
168 throw new IllegalArgumentException ("newInstance method must return Object");
169 }
170
171 Type[] parameterTypes = TypeUtils.getTypes(newInstance.getParameterTypes());
172 ce.begin_class(Constants.V1_2,
173 Constants.ACC_PUBLIC,
174 getClassName(),
175 KEY_FACTORY,
176 new Type[]{ Type.getType(keyInterface) },
177 Constants.SOURCE_FILE);
178 EmitUtils.null_constructor(ce);
179 EmitUtils.factory_method(ce, ReflectUtils.getSignature(newInstance));
180
181 int seed = 0;
182 CodeEmitter e = ce.begin_method(Constants.ACC_PUBLIC,
183 TypeUtils.parseConstructor(parameterTypes),
184 null);
185 e.load_this();
186 e.super_invoke_constructor();
187 e.load_this();
188 for (int i = 0; i < parameterTypes.length; i++) {
189 seed += parameterTypes[i].hashCode();
190 ce.declare_field(Constants.ACC_PRIVATE | Constants.ACC_FINAL,
191 getFieldName(i),
192 parameterTypes[i],
193 null);
194 e.dup();
195 e.load_arg(i);
196 e.putfield(getFieldName(i));
197 }
198 e.return_value();
199 e.end_method();
200
201 e = ce.begin_method(Constants.ACC_PUBLIC, HASH_CODE, null);
203 int hc = (constant != 0) ? constant : PRIMES[(int)(Math.abs(seed) % PRIMES.length)];
204 int hm = (multiplier != 0) ? multiplier : PRIMES[(int)(Math.abs(seed * 13) % PRIMES.length)];
205 e.push(hc);
206 for (int i = 0; i < parameterTypes.length; i++) {
207 e.load_this();
208 e.getfield(getFieldName(i));
209 EmitUtils.hash_code(e, parameterTypes[i], hm, customizer);
210 }
211 e.return_value();
212 e.end_method();
213
214 e = ce.begin_method(Constants.ACC_PUBLIC, EQUALS, null);
216 Label fail = e.make_label();
217 e.load_arg(0);
218 e.instance_of_this();
219 e.if_jump(e.EQ, fail);
220 for (int i = 0; i < parameterTypes.length; i++) {
221 e.load_this();
222 e.getfield(getFieldName(i));
223 e.load_arg(0);
224 e.checkcast_this();
225 e.getfield(getFieldName(i));
226 EmitUtils.not_equals(e, parameterTypes[i], fail, customizer);
227 }
228 e.push(1);
229 e.return_value();
230 e.mark(fail);
231 e.push(0);
232 e.return_value();
233 e.end_method();
234
235 e = ce.begin_method(Constants.ACC_PUBLIC, TO_STRING, null);
237 e.new_instance(Constants.TYPE_STRING_BUFFER);
238 e.dup();
239 e.invoke_constructor(Constants.TYPE_STRING_BUFFER);
240 for (int i = 0; i < parameterTypes.length; i++) {
241 if (i > 0) {
242 e.push(", ");
243 e.invoke_virtual(Constants.TYPE_STRING_BUFFER, APPEND_STRING);
244 }
245 e.load_this();
246 e.getfield(getFieldName(i));
247 EmitUtils.append_string(e, parameterTypes[i], EmitUtils.DEFAULT_DELIMITERS, customizer);
248 }
249 e.invoke_virtual(Constants.TYPE_STRING_BUFFER, TO_STRING);
250 e.return_value();
251 e.end_method();
252
253 ce.end_class();
254 }
255
256 private String getFieldName(int arg) {
257 return "FIELD_" + arg;
258 }
259 }
260 }
261 |
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