J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1999-2005 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package sun.misc; |
| 27 | |
| 28 | import java.io.ByteArrayOutputStream; |
| 29 | import java.io.DataOutputStream; |
| 30 | import java.io.FileOutputStream; |
| 31 | import java.io.IOException; |
| 32 | import java.io.OutputStream; |
| 33 | import java.lang.reflect.Array; |
| 34 | import java.lang.reflect.Method; |
| 35 | import java.util.ArrayList; |
| 36 | import java.util.HashMap; |
| 37 | import java.util.LinkedList; |
| 38 | import java.util.List; |
| 39 | import java.util.ListIterator; |
| 40 | import java.util.Map; |
| 41 | import sun.security.action.GetBooleanAction; |
| 42 | |
| 43 | /** |
| 44 | * ProxyGenerator contains the code to generate a dynamic proxy class |
| 45 | * for the java.lang.reflect.Proxy API. |
| 46 | * |
| 47 | * The external interfaces to ProxyGenerator is the static |
| 48 | * "generateProxyClass" method. |
| 49 | * |
| 50 | * @author Peter Jones |
| 51 | * @since 1.3 |
| 52 | */ |
| 53 | public class ProxyGenerator { |
| 54 | /* |
| 55 | * In the comments below, "JVMS" refers to The Java Virtual Machine |
| 56 | * Specification Second Edition and "JLS" refers to the original |
| 57 | * version of The Java Language Specification, unless otherwise |
| 58 | * specified. |
| 59 | */ |
| 60 | |
| 61 | /* generate 1.5-era class file version */ |
| 62 | private static final int CLASSFILE_MAJOR_VERSION = 49; |
| 63 | private static final int CLASSFILE_MINOR_VERSION = 0; |
| 64 | |
| 65 | /* |
| 66 | * beginning of constants copied from |
| 67 | * sun.tools.java.RuntimeConstants (which no longer exists): |
| 68 | */ |
| 69 | |
| 70 | /* constant pool tags */ |
| 71 | private static final int CONSTANT_UTF8 = 1; |
| 72 | private static final int CONSTANT_UNICODE = 2; |
| 73 | private static final int CONSTANT_INTEGER = 3; |
| 74 | private static final int CONSTANT_FLOAT = 4; |
| 75 | private static final int CONSTANT_LONG = 5; |
| 76 | private static final int CONSTANT_DOUBLE = 6; |
| 77 | private static final int CONSTANT_CLASS = 7; |
| 78 | private static final int CONSTANT_STRING = 8; |
| 79 | private static final int CONSTANT_FIELD = 9; |
| 80 | private static final int CONSTANT_METHOD = 10; |
| 81 | private static final int CONSTANT_INTERFACEMETHOD = 11; |
| 82 | private static final int CONSTANT_NAMEANDTYPE = 12; |
| 83 | |
| 84 | /* access and modifier flags */ |
| 85 | private static final int ACC_PUBLIC = 0x00000001; |
| 86 | private static final int ACC_PRIVATE = 0x00000002; |
| 87 | // private static final int ACC_PROTECTED = 0x00000004; |
| 88 | private static final int ACC_STATIC = 0x00000008; |
| 89 | private static final int ACC_FINAL = 0x00000010; |
| 90 | // private static final int ACC_SYNCHRONIZED = 0x00000020; |
| 91 | // private static final int ACC_VOLATILE = 0x00000040; |
| 92 | // private static final int ACC_TRANSIENT = 0x00000080; |
| 93 | // private static final int ACC_NATIVE = 0x00000100; |
| 94 | // private static final int ACC_INTERFACE = 0x00000200; |
| 95 | // private static final int ACC_ABSTRACT = 0x00000400; |
| 96 | private static final int ACC_SUPER = 0x00000020; |
| 97 | // private static final int ACC_STRICT = 0x00000800; |
| 98 | |
| 99 | /* opcodes */ |
| 100 | // private static final int opc_nop = 0; |
| 101 | private static final int opc_aconst_null = 1; |
| 102 | // private static final int opc_iconst_m1 = 2; |
| 103 | private static final int opc_iconst_0 = 3; |
| 104 | // private static final int opc_iconst_1 = 4; |
| 105 | // private static final int opc_iconst_2 = 5; |
| 106 | // private static final int opc_iconst_3 = 6; |
| 107 | // private static final int opc_iconst_4 = 7; |
| 108 | // private static final int opc_iconst_5 = 8; |
| 109 | // private static final int opc_lconst_0 = 9; |
| 110 | // private static final int opc_lconst_1 = 10; |
| 111 | // private static final int opc_fconst_0 = 11; |
| 112 | // private static final int opc_fconst_1 = 12; |
| 113 | // private static final int opc_fconst_2 = 13; |
| 114 | // private static final int opc_dconst_0 = 14; |
| 115 | // private static final int opc_dconst_1 = 15; |
| 116 | private static final int opc_bipush = 16; |
| 117 | private static final int opc_sipush = 17; |
| 118 | private static final int opc_ldc = 18; |
| 119 | private static final int opc_ldc_w = 19; |
| 120 | // private static final int opc_ldc2_w = 20; |
| 121 | private static final int opc_iload = 21; |
| 122 | private static final int opc_lload = 22; |
| 123 | private static final int opc_fload = 23; |
| 124 | private static final int opc_dload = 24; |
| 125 | private static final int opc_aload = 25; |
| 126 | private static final int opc_iload_0 = 26; |
| 127 | // private static final int opc_iload_1 = 27; |
| 128 | // private static final int opc_iload_2 = 28; |
| 129 | // private static final int opc_iload_3 = 29; |
| 130 | private static final int opc_lload_0 = 30; |
| 131 | // private static final int opc_lload_1 = 31; |
| 132 | // private static final int opc_lload_2 = 32; |
| 133 | // private static final int opc_lload_3 = 33; |
| 134 | private static final int opc_fload_0 = 34; |
| 135 | // private static final int opc_fload_1 = 35; |
| 136 | // private static final int opc_fload_2 = 36; |
| 137 | // private static final int opc_fload_3 = 37; |
| 138 | private static final int opc_dload_0 = 38; |
| 139 | // private static final int opc_dload_1 = 39; |
| 140 | // private static final int opc_dload_2 = 40; |
| 141 | // private static final int opc_dload_3 = 41; |
| 142 | private static final int opc_aload_0 = 42; |
| 143 | // private static final int opc_aload_1 = 43; |
| 144 | // private static final int opc_aload_2 = 44; |
| 145 | // private static final int opc_aload_3 = 45; |
| 146 | // private static final int opc_iaload = 46; |
| 147 | // private static final int opc_laload = 47; |
| 148 | // private static final int opc_faload = 48; |
| 149 | // private static final int opc_daload = 49; |
| 150 | // private static final int opc_aaload = 50; |
| 151 | // private static final int opc_baload = 51; |
| 152 | // private static final int opc_caload = 52; |
| 153 | // private static final int opc_saload = 53; |
| 154 | // private static final int opc_istore = 54; |
| 155 | // private static final int opc_lstore = 55; |
| 156 | // private static final int opc_fstore = 56; |
| 157 | // private static final int opc_dstore = 57; |
| 158 | private static final int opc_astore = 58; |
| 159 | // private static final int opc_istore_0 = 59; |
| 160 | // private static final int opc_istore_1 = 60; |
| 161 | // private static final int opc_istore_2 = 61; |
| 162 | // private static final int opc_istore_3 = 62; |
| 163 | // private static final int opc_lstore_0 = 63; |
| 164 | // private static final int opc_lstore_1 = 64; |
| 165 | // private static final int opc_lstore_2 = 65; |
| 166 | // private static final int opc_lstore_3 = 66; |
| 167 | // private static final int opc_fstore_0 = 67; |
| 168 | // private static final int opc_fstore_1 = 68; |
| 169 | // private static final int opc_fstore_2 = 69; |
| 170 | // private static final int opc_fstore_3 = 70; |
| 171 | // private static final int opc_dstore_0 = 71; |
| 172 | // private static final int opc_dstore_1 = 72; |
| 173 | // private static final int opc_dstore_2 = 73; |
| 174 | // private static final int opc_dstore_3 = 74; |
| 175 | private static final int opc_astore_0 = 75; |
| 176 | // private static final int opc_astore_1 = 76; |
| 177 | // private static final int opc_astore_2 = 77; |
| 178 | // private static final int opc_astore_3 = 78; |
| 179 | // private static final int opc_iastore = 79; |
| 180 | // private static final int opc_lastore = 80; |
| 181 | // private static final int opc_fastore = 81; |
| 182 | // private static final int opc_dastore = 82; |
| 183 | private static final int opc_aastore = 83; |
| 184 | // private static final int opc_bastore = 84; |
| 185 | // private static final int opc_castore = 85; |
| 186 | // private static final int opc_sastore = 86; |
| 187 | private static final int opc_pop = 87; |
| 188 | // private static final int opc_pop2 = 88; |
| 189 | private static final int opc_dup = 89; |
| 190 | // private static final int opc_dup_x1 = 90; |
| 191 | // private static final int opc_dup_x2 = 91; |
| 192 | // private static final int opc_dup2 = 92; |
| 193 | // private static final int opc_dup2_x1 = 93; |
| 194 | // private static final int opc_dup2_x2 = 94; |
| 195 | // private static final int opc_swap = 95; |
| 196 | // private static final int opc_iadd = 96; |
| 197 | // private static final int opc_ladd = 97; |
| 198 | // private static final int opc_fadd = 98; |
| 199 | // private static final int opc_dadd = 99; |
| 200 | // private static final int opc_isub = 100; |
| 201 | // private static final int opc_lsub = 101; |
| 202 | // private static final int opc_fsub = 102; |
| 203 | // private static final int opc_dsub = 103; |
| 204 | // private static final int opc_imul = 104; |
| 205 | // private static final int opc_lmul = 105; |
| 206 | // private static final int opc_fmul = 106; |
| 207 | // private static final int opc_dmul = 107; |
| 208 | // private static final int opc_idiv = 108; |
| 209 | // private static final int opc_ldiv = 109; |
| 210 | // private static final int opc_fdiv = 110; |
| 211 | // private static final int opc_ddiv = 111; |
| 212 | // private static final int opc_irem = 112; |
| 213 | // private static final int opc_lrem = 113; |
| 214 | // private static final int opc_frem = 114; |
| 215 | // private static final int opc_drem = 115; |
| 216 | // private static final int opc_ineg = 116; |
| 217 | // private static final int opc_lneg = 117; |
| 218 | // private static final int opc_fneg = 118; |
| 219 | // private static final int opc_dneg = 119; |
| 220 | // private static final int opc_ishl = 120; |
| 221 | // private static final int opc_lshl = 121; |
| 222 | // private static final int opc_ishr = 122; |
| 223 | // private static final int opc_lshr = 123; |
| 224 | // private static final int opc_iushr = 124; |
| 225 | // private static final int opc_lushr = 125; |
| 226 | // private static final int opc_iand = 126; |
| 227 | // private static final int opc_land = 127; |
| 228 | // private static final int opc_ior = 128; |
| 229 | // private static final int opc_lor = 129; |
| 230 | // private static final int opc_ixor = 130; |
| 231 | // private static final int opc_lxor = 131; |
| 232 | // private static final int opc_iinc = 132; |
| 233 | // private static final int opc_i2l = 133; |
| 234 | // private static final int opc_i2f = 134; |
| 235 | // private static final int opc_i2d = 135; |
| 236 | // private static final int opc_l2i = 136; |
| 237 | // private static final int opc_l2f = 137; |
| 238 | // private static final int opc_l2d = 138; |
| 239 | // private static final int opc_f2i = 139; |
| 240 | // private static final int opc_f2l = 140; |
| 241 | // private static final int opc_f2d = 141; |
| 242 | // private static final int opc_d2i = 142; |
| 243 | // private static final int opc_d2l = 143; |
| 244 | // private static final int opc_d2f = 144; |
| 245 | // private static final int opc_i2b = 145; |
| 246 | // private static final int opc_i2c = 146; |
| 247 | // private static final int opc_i2s = 147; |
| 248 | // private static final int opc_lcmp = 148; |
| 249 | // private static final int opc_fcmpl = 149; |
| 250 | // private static final int opc_fcmpg = 150; |
| 251 | // private static final int opc_dcmpl = 151; |
| 252 | // private static final int opc_dcmpg = 152; |
| 253 | // private static final int opc_ifeq = 153; |
| 254 | // private static final int opc_ifne = 154; |
| 255 | // private static final int opc_iflt = 155; |
| 256 | // private static final int opc_ifge = 156; |
| 257 | // private static final int opc_ifgt = 157; |
| 258 | // private static final int opc_ifle = 158; |
| 259 | // private static final int opc_if_icmpeq = 159; |
| 260 | // private static final int opc_if_icmpne = 160; |
| 261 | // private static final int opc_if_icmplt = 161; |
| 262 | // private static final int opc_if_icmpge = 162; |
| 263 | // private static final int opc_if_icmpgt = 163; |
| 264 | // private static final int opc_if_icmple = 164; |
| 265 | // private static final int opc_if_acmpeq = 165; |
| 266 | // private static final int opc_if_acmpne = 166; |
| 267 | // private static final int opc_goto = 167; |
| 268 | // private static final int opc_jsr = 168; |
| 269 | // private static final int opc_ret = 169; |
| 270 | // private static final int opc_tableswitch = 170; |
| 271 | // private static final int opc_lookupswitch = 171; |
| 272 | private static final int opc_ireturn = 172; |
| 273 | private static final int opc_lreturn = 173; |
| 274 | private static final int opc_freturn = 174; |
| 275 | private static final int opc_dreturn = 175; |
| 276 | private static final int opc_areturn = 176; |
| 277 | private static final int opc_return = 177; |
| 278 | private static final int opc_getstatic = 178; |
| 279 | private static final int opc_putstatic = 179; |
| 280 | private static final int opc_getfield = 180; |
| 281 | // private static final int opc_putfield = 181; |
| 282 | private static final int opc_invokevirtual = 182; |
| 283 | private static final int opc_invokespecial = 183; |
| 284 | private static final int opc_invokestatic = 184; |
| 285 | private static final int opc_invokeinterface = 185; |
| 286 | private static final int opc_new = 187; |
| 287 | // private static final int opc_newarray = 188; |
| 288 | private static final int opc_anewarray = 189; |
| 289 | // private static final int opc_arraylength = 190; |
| 290 | private static final int opc_athrow = 191; |
| 291 | private static final int opc_checkcast = 192; |
| 292 | // private static final int opc_instanceof = 193; |
| 293 | // private static final int opc_monitorenter = 194; |
| 294 | // private static final int opc_monitorexit = 195; |
| 295 | private static final int opc_wide = 196; |
| 296 | // private static final int opc_multianewarray = 197; |
| 297 | // private static final int opc_ifnull = 198; |
| 298 | // private static final int opc_ifnonnull = 199; |
| 299 | // private static final int opc_goto_w = 200; |
| 300 | // private static final int opc_jsr_w = 201; |
| 301 | |
| 302 | // end of constants copied from sun.tools.java.RuntimeConstants |
| 303 | |
| 304 | /** name of the superclass of proxy classes */ |
| 305 | private final static String superclassName = "java/lang/reflect/Proxy"; |
| 306 | |
| 307 | /** name of field for storing a proxy instance's invocation handler */ |
| 308 | private final static String handlerFieldName = "h"; |
| 309 | |
| 310 | /** debugging flag for saving generated class files */ |
| 311 | private final static boolean saveGeneratedFiles = |
| 312 | java.security.AccessController.doPrivileged( |
| 313 | new GetBooleanAction( |
| 314 | "sun.misc.ProxyGenerator.saveGeneratedFiles")).booleanValue(); |
| 315 | |
| 316 | /** |
| 317 | * Generate a proxy class given a name and a list of proxy interfaces. |
| 318 | */ |
| 319 | public static byte[] generateProxyClass(final String name, |
| 320 | Class[] interfaces) |
| 321 | { |
| 322 | ProxyGenerator gen = new ProxyGenerator(name, interfaces); |
| 323 | final byte[] classFile = gen.generateClassFile(); |
| 324 | |
| 325 | if (saveGeneratedFiles) { |
| 326 | java.security.AccessController.doPrivileged( |
| 327 | new java.security.PrivilegedAction() { |
| 328 | public Object run() { |
| 329 | try { |
| 330 | FileOutputStream file = |
| 331 | new FileOutputStream(dotToSlash(name) + ".class"); |
| 332 | file.write(classFile); |
| 333 | file.close(); |
| 334 | return null; |
| 335 | } catch (IOException e) { |
| 336 | throw new InternalError( |
| 337 | "I/O exception saving generated file: " + e); |
| 338 | } |
| 339 | } |
| 340 | }); |
| 341 | } |
| 342 | |
| 343 | return classFile; |
| 344 | } |
| 345 | |
| 346 | /* preloaded Method objects for methods in java.lang.Object */ |
| 347 | private static Method hashCodeMethod; |
| 348 | private static Method equalsMethod; |
| 349 | private static Method toStringMethod; |
| 350 | static { |
| 351 | try { |
| 352 | hashCodeMethod = Object.class.getMethod("hashCode"); |
| 353 | equalsMethod = |
| 354 | Object.class.getMethod("equals", new Class[] { Object.class }); |
| 355 | toStringMethod = Object.class.getMethod("toString"); |
| 356 | } catch (NoSuchMethodException e) { |
| 357 | throw new NoSuchMethodError(e.getMessage()); |
| 358 | } |
| 359 | } |
| 360 | |
| 361 | /** name of proxy class */ |
| 362 | private String className; |
| 363 | |
| 364 | /** proxy interfaces */ |
| 365 | private Class[] interfaces; |
| 366 | |
| 367 | /** constant pool of class being generated */ |
| 368 | private ConstantPool cp = new ConstantPool(); |
| 369 | |
| 370 | /** FieldInfo struct for each field of generated class */ |
| 371 | private List<FieldInfo> fields = new ArrayList<FieldInfo>(); |
| 372 | |
| 373 | /** MethodInfo struct for each method of generated class */ |
| 374 | private List<MethodInfo> methods = new ArrayList<MethodInfo>(); |
| 375 | |
| 376 | /** |
| 377 | * maps method signature string to list of ProxyMethod objects for |
| 378 | * proxy methods with that signature |
| 379 | */ |
| 380 | private Map<String, List<ProxyMethod>> proxyMethods = |
| 381 | new HashMap<String,List<ProxyMethod>>(); |
| 382 | |
| 383 | /** count of ProxyMethod objects added to proxyMethods */ |
| 384 | private int proxyMethodCount = 0; |
| 385 | |
| 386 | /** |
| 387 | * Construct a ProxyGenerator to generate a proxy class with the |
| 388 | * specified name and for the given interfaces. |
| 389 | * |
| 390 | * A ProxyGenerator object contains the state for the ongoing |
| 391 | * generation of a particular proxy class. |
| 392 | */ |
| 393 | private ProxyGenerator(String className, Class[] interfaces) { |
| 394 | this.className = className; |
| 395 | this.interfaces = interfaces; |
| 396 | } |
| 397 | |
| 398 | /** |
| 399 | * Generate a class file for the proxy class. This method drives the |
| 400 | * class file generation process. |
| 401 | */ |
| 402 | private byte[] generateClassFile() { |
| 403 | |
| 404 | /* ============================================================ |
| 405 | * Step 1: Assemble ProxyMethod objects for all methods to |
| 406 | * generate proxy dispatching code for. |
| 407 | */ |
| 408 | |
| 409 | /* |
| 410 | * Record that proxy methods are needed for the hashCode, equals, |
| 411 | * and toString methods of java.lang.Object. This is done before |
| 412 | * the methods from the proxy interfaces so that the methods from |
| 413 | * java.lang.Object take precedence over duplicate methods in the |
| 414 | * proxy interfaces. |
| 415 | */ |
| 416 | addProxyMethod(hashCodeMethod, Object.class); |
| 417 | addProxyMethod(equalsMethod, Object.class); |
| 418 | addProxyMethod(toStringMethod, Object.class); |
| 419 | |
| 420 | /* |
| 421 | * Now record all of the methods from the proxy interfaces, giving |
| 422 | * earlier interfaces precedence over later ones with duplicate |
| 423 | * methods. |
| 424 | */ |
| 425 | for (int i = 0; i < interfaces.length; i++) { |
| 426 | Method[] methods = interfaces[i].getMethods(); |
| 427 | for (int j = 0; j < methods.length; j++) { |
| 428 | addProxyMethod(methods[j], interfaces[i]); |
| 429 | } |
| 430 | } |
| 431 | |
| 432 | /* |
| 433 | * For each set of proxy methods with the same signature, |
| 434 | * verify that the methods' return types are compatible. |
| 435 | */ |
| 436 | for (List<ProxyMethod> sigmethods : proxyMethods.values()) { |
| 437 | checkReturnTypes(sigmethods); |
| 438 | } |
| 439 | |
| 440 | /* ============================================================ |
| 441 | * Step 2: Assemble FieldInfo and MethodInfo structs for all of |
| 442 | * fields and methods in the class we are generating. |
| 443 | */ |
| 444 | try { |
| 445 | methods.add(generateConstructor()); |
| 446 | |
| 447 | for (List<ProxyMethod> sigmethods : proxyMethods.values()) { |
| 448 | for (ProxyMethod pm : sigmethods) { |
| 449 | |
| 450 | // add static field for method's Method object |
| 451 | fields.add(new FieldInfo(pm.methodFieldName, |
| 452 | "Ljava/lang/reflect/Method;", |
| 453 | ACC_PRIVATE | ACC_STATIC)); |
| 454 | |
| 455 | // generate code for proxy method and add it |
| 456 | methods.add(pm.generateMethod()); |
| 457 | } |
| 458 | } |
| 459 | |
| 460 | methods.add(generateStaticInitializer()); |
| 461 | |
| 462 | } catch (IOException e) { |
| 463 | throw new InternalError("unexpected I/O Exception"); |
| 464 | } |
| 465 | |
| 466 | if (methods.size() > 65535) { |
| 467 | throw new IllegalArgumentException("method limit exceeded"); |
| 468 | } |
| 469 | if (fields.size() > 65535) { |
| 470 | throw new IllegalArgumentException("field limit exceeded"); |
| 471 | } |
| 472 | |
| 473 | /* ============================================================ |
| 474 | * Step 3: Write the final class file. |
| 475 | */ |
| 476 | |
| 477 | /* |
| 478 | * Make sure that constant pool indexes are reserved for the |
| 479 | * following items before starting to write the final class file. |
| 480 | */ |
| 481 | cp.getClass(dotToSlash(className)); |
| 482 | cp.getClass(superclassName); |
| 483 | for (int i = 0; i < interfaces.length; i++) { |
| 484 | cp.getClass(dotToSlash(interfaces[i].getName())); |
| 485 | } |
| 486 | |
| 487 | /* |
| 488 | * Disallow new constant pool additions beyond this point, since |
| 489 | * we are about to write the final constant pool table. |
| 490 | */ |
| 491 | cp.setReadOnly(); |
| 492 | |
| 493 | ByteArrayOutputStream bout = new ByteArrayOutputStream(); |
| 494 | DataOutputStream dout = new DataOutputStream(bout); |
| 495 | |
| 496 | try { |
| 497 | /* |
| 498 | * Write all the items of the "ClassFile" structure. |
| 499 | * See JVMS section 4.1. |
| 500 | */ |
| 501 | // u4 magic; |
| 502 | dout.writeInt(0xCAFEBABE); |
| 503 | // u2 minor_version; |
| 504 | dout.writeShort(CLASSFILE_MINOR_VERSION); |
| 505 | // u2 major_version; |
| 506 | dout.writeShort(CLASSFILE_MAJOR_VERSION); |
| 507 | |
| 508 | cp.write(dout); // (write constant pool) |
| 509 | |
| 510 | // u2 access_flags; |
| 511 | dout.writeShort(ACC_PUBLIC | ACC_FINAL | ACC_SUPER); |
| 512 | // u2 this_class; |
| 513 | dout.writeShort(cp.getClass(dotToSlash(className))); |
| 514 | // u2 super_class; |
| 515 | dout.writeShort(cp.getClass(superclassName)); |
| 516 | |
| 517 | // u2 interfaces_count; |
| 518 | dout.writeShort(interfaces.length); |
| 519 | // u2 interfaces[interfaces_count]; |
| 520 | for (int i = 0; i < interfaces.length; i++) { |
| 521 | dout.writeShort(cp.getClass( |
| 522 | dotToSlash(interfaces[i].getName()))); |
| 523 | } |
| 524 | |
| 525 | // u2 fields_count; |
| 526 | dout.writeShort(fields.size()); |
| 527 | // field_info fields[fields_count]; |
| 528 | for (FieldInfo f : fields) { |
| 529 | f.write(dout); |
| 530 | } |
| 531 | |
| 532 | // u2 methods_count; |
| 533 | dout.writeShort(methods.size()); |
| 534 | // method_info methods[methods_count]; |
| 535 | for (MethodInfo m : methods) { |
| 536 | m.write(dout); |
| 537 | } |
| 538 | |
| 539 | // u2 attributes_count; |
| 540 | dout.writeShort(0); // (no ClassFile attributes for proxy classes) |
| 541 | |
| 542 | } catch (IOException e) { |
| 543 | throw new InternalError("unexpected I/O Exception"); |
| 544 | } |
| 545 | |
| 546 | return bout.toByteArray(); |
| 547 | } |
| 548 | |
| 549 | /** |
| 550 | * Add another method to be proxied, either by creating a new |
| 551 | * ProxyMethod object or augmenting an old one for a duplicate |
| 552 | * method. |
| 553 | * |
| 554 | * "fromClass" indicates the proxy interface that the method was |
| 555 | * found through, which may be different from (a subinterface of) |
| 556 | * the method's "declaring class". Note that the first Method |
| 557 | * object passed for a given name and descriptor identifies the |
| 558 | * Method object (and thus the declaring class) that will be |
| 559 | * passed to the invocation handler's "invoke" method for a given |
| 560 | * set of duplicate methods. |
| 561 | */ |
| 562 | private void addProxyMethod(Method m, Class fromClass) { |
| 563 | String name = m.getName(); |
| 564 | Class[] parameterTypes = m.getParameterTypes(); |
| 565 | Class returnType = m.getReturnType(); |
| 566 | Class[] exceptionTypes = m.getExceptionTypes(); |
| 567 | |
| 568 | String sig = name + getParameterDescriptors(parameterTypes); |
| 569 | List<ProxyMethod> sigmethods = proxyMethods.get(sig); |
| 570 | if (sigmethods != null) { |
| 571 | for (ProxyMethod pm : sigmethods) { |
| 572 | if (returnType == pm.returnType) { |
| 573 | /* |
| 574 | * Found a match: reduce exception types to the |
| 575 | * greatest set of exceptions that can thrown |
| 576 | * compatibly with the throws clauses of both |
| 577 | * overridden methods. |
| 578 | */ |
| 579 | List<Class> legalExceptions = new ArrayList<Class>(); |
| 580 | collectCompatibleTypes( |
| 581 | exceptionTypes, pm.exceptionTypes, legalExceptions); |
| 582 | collectCompatibleTypes( |
| 583 | pm.exceptionTypes, exceptionTypes, legalExceptions); |
| 584 | pm.exceptionTypes = new Class[legalExceptions.size()]; |
| 585 | pm.exceptionTypes = |
| 586 | legalExceptions.toArray(pm.exceptionTypes); |
| 587 | return; |
| 588 | } |
| 589 | } |
| 590 | } else { |
| 591 | sigmethods = new ArrayList<ProxyMethod>(3); |
| 592 | proxyMethods.put(sig, sigmethods); |
| 593 | } |
| 594 | sigmethods.add(new ProxyMethod(name, parameterTypes, returnType, |
| 595 | exceptionTypes, fromClass)); |
| 596 | } |
| 597 | |
| 598 | /** |
| 599 | * For a given set of proxy methods with the same signature, check |
| 600 | * that their return types are compatible according to the Proxy |
| 601 | * specification. |
| 602 | * |
| 603 | * Specifically, if there is more than one such method, then all |
| 604 | * of the return types must be reference types, and there must be |
| 605 | * one return type that is assignable to each of the rest of them. |
| 606 | */ |
| 607 | private static void checkReturnTypes(List<ProxyMethod> methods) { |
| 608 | /* |
| 609 | * If there is only one method with a given signature, there |
| 610 | * cannot be a conflict. This is the only case in which a |
| 611 | * primitive (or void) return type is allowed. |
| 612 | */ |
| 613 | if (methods.size() < 2) { |
| 614 | return; |
| 615 | } |
| 616 | |
| 617 | /* |
| 618 | * List of return types that are not yet known to be |
| 619 | * assignable from ("covered" by) any of the others. |
| 620 | */ |
| 621 | LinkedList<Class> uncoveredReturnTypes = new LinkedList<Class>(); |
| 622 | |
| 623 | nextNewReturnType: |
| 624 | for (ProxyMethod pm : methods) { |
| 625 | Class newReturnType = pm.returnType; |
| 626 | if (newReturnType.isPrimitive()) { |
| 627 | throw new IllegalArgumentException( |
| 628 | "methods with same signature " + |
| 629 | getFriendlyMethodSignature(pm.methodName, |
| 630 | pm.parameterTypes) + |
| 631 | " but incompatible return types: " + |
| 632 | newReturnType.getName() + " and others"); |
| 633 | } |
| 634 | boolean added = false; |
| 635 | |
| 636 | /* |
| 637 | * Compare the new return type to the existing uncovered |
| 638 | * return types. |
| 639 | */ |
| 640 | ListIterator<Class> liter = uncoveredReturnTypes.listIterator(); |
| 641 | while (liter.hasNext()) { |
| 642 | Class uncoveredReturnType = liter.next(); |
| 643 | |
| 644 | /* |
| 645 | * If an existing uncovered return type is assignable |
| 646 | * to this new one, then we can forget the new one. |
| 647 | */ |
| 648 | if (newReturnType.isAssignableFrom(uncoveredReturnType)) { |
| 649 | assert !added; |
| 650 | continue nextNewReturnType; |
| 651 | } |
| 652 | |
| 653 | /* |
| 654 | * If the new return type is assignable to an existing |
| 655 | * uncovered one, then should replace the existing one |
| 656 | * with the new one (or just forget the existing one, |
| 657 | * if the new one has already be put in the list). |
| 658 | */ |
| 659 | if (uncoveredReturnType.isAssignableFrom(newReturnType)) { |
| 660 | // (we can assume that each return type is unique) |
| 661 | if (!added) { |
| 662 | liter.set(newReturnType); |
| 663 | added = true; |
| 664 | } else { |
| 665 | liter.remove(); |
| 666 | } |
| 667 | } |
| 668 | } |
| 669 | |
| 670 | /* |
| 671 | * If we got through the list of existing uncovered return |
| 672 | * types without an assignability relationship, then add |
| 673 | * the new return type to the list of uncovered ones. |
| 674 | */ |
| 675 | if (!added) { |
| 676 | uncoveredReturnTypes.add(newReturnType); |
| 677 | } |
| 678 | } |
| 679 | |
| 680 | /* |
| 681 | * We shouldn't end up with more than one return type that is |
| 682 | * not assignable from any of the others. |
| 683 | */ |
| 684 | if (uncoveredReturnTypes.size() > 1) { |
| 685 | ProxyMethod pm = methods.get(0); |
| 686 | throw new IllegalArgumentException( |
| 687 | "methods with same signature " + |
| 688 | getFriendlyMethodSignature(pm.methodName, pm.parameterTypes) + |
| 689 | " but incompatible return types: " + uncoveredReturnTypes); |
| 690 | } |
| 691 | } |
| 692 | |
| 693 | /** |
| 694 | * A FieldInfo object contains information about a particular field |
| 695 | * in the class being generated. The class mirrors the data items of |
| 696 | * the "field_info" structure of the class file format (see JVMS 4.5). |
| 697 | */ |
| 698 | private class FieldInfo { |
| 699 | public int accessFlags; |
| 700 | public String name; |
| 701 | public String descriptor; |
| 702 | |
| 703 | public FieldInfo(String name, String descriptor, int accessFlags) { |
| 704 | this.name = name; |
| 705 | this.descriptor = descriptor; |
| 706 | this.accessFlags = accessFlags; |
| 707 | |
| 708 | /* |
| 709 | * Make sure that constant pool indexes are reserved for the |
| 710 | * following items before starting to write the final class file. |
| 711 | */ |
| 712 | cp.getUtf8(name); |
| 713 | cp.getUtf8(descriptor); |
| 714 | } |
| 715 | |
| 716 | public void write(DataOutputStream out) throws IOException { |
| 717 | /* |
| 718 | * Write all the items of the "field_info" structure. |
| 719 | * See JVMS section 4.5. |
| 720 | */ |
| 721 | // u2 access_flags; |
| 722 | out.writeShort(accessFlags); |
| 723 | // u2 name_index; |
| 724 | out.writeShort(cp.getUtf8(name)); |
| 725 | // u2 descriptor_index; |
| 726 | out.writeShort(cp.getUtf8(descriptor)); |
| 727 | // u2 attributes_count; |
| 728 | out.writeShort(0); // (no field_info attributes for proxy classes) |
| 729 | } |
| 730 | } |
| 731 | |
| 732 | /** |
| 733 | * An ExceptionTableEntry object holds values for the data items of |
| 734 | * an entry in the "exception_table" item of the "Code" attribute of |
| 735 | * "method_info" structures (see JVMS 4.7.3). |
| 736 | */ |
| 737 | private static class ExceptionTableEntry { |
| 738 | public short startPc; |
| 739 | public short endPc; |
| 740 | public short handlerPc; |
| 741 | public short catchType; |
| 742 | |
| 743 | public ExceptionTableEntry(short startPc, short endPc, |
| 744 | short handlerPc, short catchType) |
| 745 | { |
| 746 | this.startPc = startPc; |
| 747 | this.endPc = endPc; |
| 748 | this.handlerPc = handlerPc; |
| 749 | this.catchType = catchType; |
| 750 | } |
| 751 | }; |
| 752 | |
| 753 | /** |
| 754 | * A MethodInfo object contains information about a particular method |
| 755 | * in the class being generated. This class mirrors the data items of |
| 756 | * the "method_info" structure of the class file format (see JVMS 4.6). |
| 757 | */ |
| 758 | private class MethodInfo { |
| 759 | public int accessFlags; |
| 760 | public String name; |
| 761 | public String descriptor; |
| 762 | public short maxStack; |
| 763 | public short maxLocals; |
| 764 | public ByteArrayOutputStream code = new ByteArrayOutputStream(); |
| 765 | public List<ExceptionTableEntry> exceptionTable = |
| 766 | new ArrayList<ExceptionTableEntry>(); |
| 767 | public short[] declaredExceptions; |
| 768 | |
| 769 | public MethodInfo(String name, String descriptor, int accessFlags) { |
| 770 | this.name = name; |
| 771 | this.descriptor = descriptor; |
| 772 | this.accessFlags = accessFlags; |
| 773 | |
| 774 | /* |
| 775 | * Make sure that constant pool indexes are reserved for the |
| 776 | * following items before starting to write the final class file. |
| 777 | */ |
| 778 | cp.getUtf8(name); |
| 779 | cp.getUtf8(descriptor); |
| 780 | cp.getUtf8("Code"); |
| 781 | cp.getUtf8("Exceptions"); |
| 782 | } |
| 783 | |
| 784 | public void write(DataOutputStream out) throws IOException { |
| 785 | /* |
| 786 | * Write all the items of the "method_info" structure. |
| 787 | * See JVMS section 4.6. |
| 788 | */ |
| 789 | // u2 access_flags; |
| 790 | out.writeShort(accessFlags); |
| 791 | // u2 name_index; |
| 792 | out.writeShort(cp.getUtf8(name)); |
| 793 | // u2 descriptor_index; |
| 794 | out.writeShort(cp.getUtf8(descriptor)); |
| 795 | // u2 attributes_count; |
| 796 | out.writeShort(2); // (two method_info attributes:) |
| 797 | |
| 798 | // Write "Code" attribute. See JVMS section 4.7.3. |
| 799 | |
| 800 | // u2 attribute_name_index; |
| 801 | out.writeShort(cp.getUtf8("Code")); |
| 802 | // u4 attribute_length; |
| 803 | out.writeInt(12 + code.size() + 8 * exceptionTable.size()); |
| 804 | // u2 max_stack; |
| 805 | out.writeShort(maxStack); |
| 806 | // u2 max_locals; |
| 807 | out.writeShort(maxLocals); |
| 808 | // u2 code_length; |
| 809 | out.writeInt(code.size()); |
| 810 | // u1 code[code_length]; |
| 811 | code.writeTo(out); |
| 812 | // u2 exception_table_length; |
| 813 | out.writeShort(exceptionTable.size()); |
| 814 | for (ExceptionTableEntry e : exceptionTable) { |
| 815 | // u2 start_pc; |
| 816 | out.writeShort(e.startPc); |
| 817 | // u2 end_pc; |
| 818 | out.writeShort(e.endPc); |
| 819 | // u2 handler_pc; |
| 820 | out.writeShort(e.handlerPc); |
| 821 | // u2 catch_type; |
| 822 | out.writeShort(e.catchType); |
| 823 | } |
| 824 | // u2 attributes_count; |
| 825 | out.writeShort(0); |
| 826 | |
| 827 | // write "Exceptions" attribute. See JVMS section 4.7.4. |
| 828 | |
| 829 | // u2 attribute_name_index; |
| 830 | out.writeShort(cp.getUtf8("Exceptions")); |
| 831 | // u4 attributes_length; |
| 832 | out.writeInt(2 + 2 * declaredExceptions.length); |
| 833 | // u2 number_of_exceptions; |
| 834 | out.writeShort(declaredExceptions.length); |
| 835 | // u2 exception_index_table[number_of_exceptions]; |
| 836 | for (int i = 0; i < declaredExceptions.length; i++) { |
| 837 | out.writeShort(declaredExceptions[i]); |
| 838 | } |
| 839 | } |
| 840 | |
| 841 | } |
| 842 | |
| 843 | /** |
| 844 | * A ProxyMethod object represents a proxy method in the proxy class |
| 845 | * being generated: a method whose implementation will encode and |
| 846 | * dispatch invocations to the proxy instance's invocation handler. |
| 847 | */ |
| 848 | private class ProxyMethod { |
| 849 | |
| 850 | public String methodName; |
| 851 | public Class[] parameterTypes; |
| 852 | public Class returnType; |
| 853 | public Class[] exceptionTypes; |
| 854 | public Class fromClass; |
| 855 | public String methodFieldName; |
| 856 | |
| 857 | private ProxyMethod(String methodName, Class[] parameterTypes, |
| 858 | Class returnType, Class[] exceptionTypes, |
| 859 | Class fromClass) |
| 860 | { |
| 861 | this.methodName = methodName; |
| 862 | this.parameterTypes = parameterTypes; |
| 863 | this.returnType = returnType; |
| 864 | this.exceptionTypes = exceptionTypes; |
| 865 | this.fromClass = fromClass; |
| 866 | this.methodFieldName = "m" + proxyMethodCount++; |
| 867 | } |
| 868 | |
| 869 | /** |
| 870 | * Return a MethodInfo object for this method, including generating |
| 871 | * the code and exception table entry. |
| 872 | */ |
| 873 | private MethodInfo generateMethod() throws IOException { |
| 874 | String desc = getMethodDescriptor(parameterTypes, returnType); |
| 875 | MethodInfo minfo = new MethodInfo(methodName, desc, |
| 876 | ACC_PUBLIC | ACC_FINAL); |
| 877 | |
| 878 | int[] parameterSlot = new int[parameterTypes.length]; |
| 879 | int nextSlot = 1; |
| 880 | for (int i = 0; i < parameterSlot.length; i++) { |
| 881 | parameterSlot[i] = nextSlot; |
| 882 | nextSlot += getWordsPerType(parameterTypes[i]); |
| 883 | } |
| 884 | int localSlot0 = nextSlot; |
| 885 | short pc, tryBegin = 0, tryEnd; |
| 886 | |
| 887 | DataOutputStream out = new DataOutputStream(minfo.code); |
| 888 | |
| 889 | code_aload(0, out); |
| 890 | |
| 891 | out.writeByte(opc_getfield); |
| 892 | out.writeShort(cp.getFieldRef( |
| 893 | superclassName, |
| 894 | handlerFieldName, "Ljava/lang/reflect/InvocationHandler;")); |
| 895 | |
| 896 | code_aload(0, out); |
| 897 | |
| 898 | out.writeByte(opc_getstatic); |
| 899 | out.writeShort(cp.getFieldRef( |
| 900 | dotToSlash(className), |
| 901 | methodFieldName, "Ljava/lang/reflect/Method;")); |
| 902 | |
| 903 | if (parameterTypes.length > 0) { |
| 904 | |
| 905 | code_ipush(parameterTypes.length, out); |
| 906 | |
| 907 | out.writeByte(opc_anewarray); |
| 908 | out.writeShort(cp.getClass("java/lang/Object")); |
| 909 | |
| 910 | for (int i = 0; i < parameterTypes.length; i++) { |
| 911 | |
| 912 | out.writeByte(opc_dup); |
| 913 | |
| 914 | code_ipush(i, out); |
| 915 | |
| 916 | codeWrapArgument(parameterTypes[i], parameterSlot[i], out); |
| 917 | |
| 918 | out.writeByte(opc_aastore); |
| 919 | } |
| 920 | } else { |
| 921 | |
| 922 | out.writeByte(opc_aconst_null); |
| 923 | } |
| 924 | |
| 925 | out.writeByte(opc_invokeinterface); |
| 926 | out.writeShort(cp.getInterfaceMethodRef( |
| 927 | "java/lang/reflect/InvocationHandler", |
| 928 | "invoke", |
| 929 | "(Ljava/lang/Object;Ljava/lang/reflect/Method;" + |
| 930 | "[Ljava/lang/Object;)Ljava/lang/Object;")); |
| 931 | out.writeByte(4); |
| 932 | out.writeByte(0); |
| 933 | |
| 934 | if (returnType == void.class) { |
| 935 | |
| 936 | out.writeByte(opc_pop); |
| 937 | |
| 938 | out.writeByte(opc_return); |
| 939 | |
| 940 | } else { |
| 941 | |
| 942 | codeUnwrapReturnValue(returnType, out); |
| 943 | } |
| 944 | |
| 945 | tryEnd = pc = (short) minfo.code.size(); |
| 946 | |
| 947 | List<Class> catchList = computeUniqueCatchList(exceptionTypes); |
| 948 | if (catchList.size() > 0) { |
| 949 | |
| 950 | for (Class ex : catchList) { |
| 951 | minfo.exceptionTable.add(new ExceptionTableEntry( |
| 952 | tryBegin, tryEnd, pc, |
| 953 | cp.getClass(dotToSlash(ex.getName())))); |
| 954 | } |
| 955 | |
| 956 | out.writeByte(opc_athrow); |
| 957 | |
| 958 | pc = (short) minfo.code.size(); |
| 959 | |
| 960 | minfo.exceptionTable.add(new ExceptionTableEntry( |
| 961 | tryBegin, tryEnd, pc, cp.getClass("java/lang/Throwable"))); |
| 962 | |
| 963 | code_astore(localSlot0, out); |
| 964 | |
| 965 | out.writeByte(opc_new); |
| 966 | out.writeShort(cp.getClass( |
| 967 | "java/lang/reflect/UndeclaredThrowableException")); |
| 968 | |
| 969 | out.writeByte(opc_dup); |
| 970 | |
| 971 | code_aload(localSlot0, out); |
| 972 | |
| 973 | out.writeByte(opc_invokespecial); |
| 974 | |
| 975 | out.writeShort(cp.getMethodRef( |
| 976 | "java/lang/reflect/UndeclaredThrowableException", |
| 977 | "<init>", "(Ljava/lang/Throwable;)V")); |
| 978 | |
| 979 | out.writeByte(opc_athrow); |
| 980 | } |
| 981 | |
| 982 | if (minfo.code.size() > 65535) { |
| 983 | throw new IllegalArgumentException("code size limit exceeded"); |
| 984 | } |
| 985 | |
| 986 | minfo.maxStack = 10; |
| 987 | minfo.maxLocals = (short) (localSlot0 + 1); |
| 988 | minfo.declaredExceptions = new short[exceptionTypes.length]; |
| 989 | for (int i = 0; i < exceptionTypes.length; i++) { |
| 990 | minfo.declaredExceptions[i] = cp.getClass( |
| 991 | dotToSlash(exceptionTypes[i].getName())); |
| 992 | } |
| 993 | |
| 994 | return minfo; |
| 995 | } |
| 996 | |
| 997 | /** |
| 998 | * Generate code for wrapping an argument of the given type |
| 999 | * whose value can be found at the specified local variable |
| 1000 | * index, in order for it to be passed (as an Object) to the |
| 1001 | * invocation handler's "invoke" method. The code is written |
| 1002 | * to the supplied stream. |
| 1003 | */ |
| 1004 | private void codeWrapArgument(Class type, int slot, |
| 1005 | DataOutputStream out) |
| 1006 | throws IOException |
| 1007 | { |
| 1008 | if (type.isPrimitive()) { |
| 1009 | PrimitiveTypeInfo prim = PrimitiveTypeInfo.get(type); |
| 1010 | |
| 1011 | if (type == int.class || |
| 1012 | type == boolean.class || |
| 1013 | type == byte.class || |
| 1014 | type == char.class || |
| 1015 | type == short.class) |
| 1016 | { |
| 1017 | code_iload(slot, out); |
| 1018 | } else if (type == long.class) { |
| 1019 | code_lload(slot, out); |
| 1020 | } else if (type == float.class) { |
| 1021 | code_fload(slot, out); |
| 1022 | } else if (type == double.class) { |
| 1023 | code_dload(slot, out); |
| 1024 | } else { |
| 1025 | throw new AssertionError(); |
| 1026 | } |
| 1027 | |
| 1028 | out.writeByte(opc_invokestatic); |
| 1029 | out.writeShort(cp.getMethodRef( |
| 1030 | prim.wrapperClassName, |
| 1031 | "valueOf", prim.wrapperValueOfDesc)); |
| 1032 | |
| 1033 | } else { |
| 1034 | |
| 1035 | code_aload(slot, out); |
| 1036 | } |
| 1037 | } |
| 1038 | |
| 1039 | /** |
| 1040 | * Generate code for unwrapping a return value of the given |
| 1041 | * type from the invocation handler's "invoke" method (as type |
| 1042 | * Object) to its correct type. The code is written to the |
| 1043 | * supplied stream. |
| 1044 | */ |
| 1045 | private void codeUnwrapReturnValue(Class type, DataOutputStream out) |
| 1046 | throws IOException |
| 1047 | { |
| 1048 | if (type.isPrimitive()) { |
| 1049 | PrimitiveTypeInfo prim = PrimitiveTypeInfo.get(type); |
| 1050 | |
| 1051 | out.writeByte(opc_checkcast); |
| 1052 | out.writeShort(cp.getClass(prim.wrapperClassName)); |
| 1053 | |
| 1054 | out.writeByte(opc_invokevirtual); |
| 1055 | out.writeShort(cp.getMethodRef( |
| 1056 | prim.wrapperClassName, |
| 1057 | prim.unwrapMethodName, prim.unwrapMethodDesc)); |
| 1058 | |
| 1059 | if (type == int.class || |
| 1060 | type == boolean.class || |
| 1061 | type == byte.class || |
| 1062 | type == char.class || |
| 1063 | type == short.class) |
| 1064 | { |
| 1065 | out.writeByte(opc_ireturn); |
| 1066 | } else if (type == long.class) { |
| 1067 | out.writeByte(opc_lreturn); |
| 1068 | } else if (type == float.class) { |
| 1069 | out.writeByte(opc_freturn); |
| 1070 | } else if (type == double.class) { |
| 1071 | out.writeByte(opc_dreturn); |
| 1072 | } else { |
| 1073 | throw new AssertionError(); |
| 1074 | } |
| 1075 | |
| 1076 | } else { |
| 1077 | |
| 1078 | out.writeByte(opc_checkcast); |
| 1079 | out.writeShort(cp.getClass(dotToSlash(type.getName()))); |
| 1080 | |
| 1081 | out.writeByte(opc_areturn); |
| 1082 | } |
| 1083 | } |
| 1084 | |
| 1085 | /** |
| 1086 | * Generate code for initializing the static field that stores |
| 1087 | * the Method object for this proxy method. The code is written |
| 1088 | * to the supplied stream. |
| 1089 | */ |
| 1090 | private void codeFieldInitialization(DataOutputStream out) |
| 1091 | throws IOException |
| 1092 | { |
| 1093 | codeClassForName(fromClass, out); |
| 1094 | |
| 1095 | code_ldc(cp.getString(methodName), out); |
| 1096 | |
| 1097 | code_ipush(parameterTypes.length, out); |
| 1098 | |
| 1099 | out.writeByte(opc_anewarray); |
| 1100 | out.writeShort(cp.getClass("java/lang/Class")); |
| 1101 | |
| 1102 | for (int i = 0; i < parameterTypes.length; i++) { |
| 1103 | |
| 1104 | out.writeByte(opc_dup); |
| 1105 | |
| 1106 | code_ipush(i, out); |
| 1107 | |
| 1108 | if (parameterTypes[i].isPrimitive()) { |
| 1109 | PrimitiveTypeInfo prim = |
| 1110 | PrimitiveTypeInfo.get(parameterTypes[i]); |
| 1111 | |
| 1112 | out.writeByte(opc_getstatic); |
| 1113 | out.writeShort(cp.getFieldRef( |
| 1114 | prim.wrapperClassName, "TYPE", "Ljava/lang/Class;")); |
| 1115 | |
| 1116 | } else { |
| 1117 | codeClassForName(parameterTypes[i], out); |
| 1118 | } |
| 1119 | |
| 1120 | out.writeByte(opc_aastore); |
| 1121 | } |
| 1122 | |
| 1123 | out.writeByte(opc_invokevirtual); |
| 1124 | out.writeShort(cp.getMethodRef( |
| 1125 | "java/lang/Class", |
| 1126 | "getMethod", |
| 1127 | "(Ljava/lang/String;[Ljava/lang/Class;)" + |
| 1128 | "Ljava/lang/reflect/Method;")); |
| 1129 | |
| 1130 | out.writeByte(opc_putstatic); |
| 1131 | out.writeShort(cp.getFieldRef( |
| 1132 | dotToSlash(className), |
| 1133 | methodFieldName, "Ljava/lang/reflect/Method;")); |
| 1134 | } |
| 1135 | } |
| 1136 | |
| 1137 | /** |
| 1138 | * Generate the constructor method for the proxy class. |
| 1139 | */ |
| 1140 | private MethodInfo generateConstructor() throws IOException { |
| 1141 | MethodInfo minfo = new MethodInfo( |
| 1142 | "<init>", "(Ljava/lang/reflect/InvocationHandler;)V", |
| 1143 | ACC_PUBLIC); |
| 1144 | |
| 1145 | DataOutputStream out = new DataOutputStream(minfo.code); |
| 1146 | |
| 1147 | code_aload(0, out); |
| 1148 | |
| 1149 | code_aload(1, out); |
| 1150 | |
| 1151 | out.writeByte(opc_invokespecial); |
| 1152 | out.writeShort(cp.getMethodRef( |
| 1153 | superclassName, |
| 1154 | "<init>", "(Ljava/lang/reflect/InvocationHandler;)V")); |
| 1155 | |
| 1156 | out.writeByte(opc_return); |
| 1157 | |
| 1158 | minfo.maxStack = 10; |
| 1159 | minfo.maxLocals = 2; |
| 1160 | minfo.declaredExceptions = new short[0]; |
| 1161 | |
| 1162 | return minfo; |
| 1163 | } |
| 1164 | |
| 1165 | /** |
| 1166 | * Generate the static initializer method for the proxy class. |
| 1167 | */ |
| 1168 | private MethodInfo generateStaticInitializer() throws IOException { |
| 1169 | MethodInfo minfo = new MethodInfo( |
| 1170 | "<clinit>", "()V", ACC_STATIC); |
| 1171 | |
| 1172 | int localSlot0 = 1; |
| 1173 | short pc, tryBegin = 0, tryEnd; |
| 1174 | |
| 1175 | DataOutputStream out = new DataOutputStream(minfo.code); |
| 1176 | |
| 1177 | for (List<ProxyMethod> sigmethods : proxyMethods.values()) { |
| 1178 | for (ProxyMethod pm : sigmethods) { |
| 1179 | pm.codeFieldInitialization(out); |
| 1180 | } |
| 1181 | } |
| 1182 | |
| 1183 | out.writeByte(opc_return); |
| 1184 | |
| 1185 | tryEnd = pc = (short) minfo.code.size(); |
| 1186 | |
| 1187 | minfo.exceptionTable.add(new ExceptionTableEntry( |
| 1188 | tryBegin, tryEnd, pc, |
| 1189 | cp.getClass("java/lang/NoSuchMethodException"))); |
| 1190 | |
| 1191 | code_astore(localSlot0, out); |
| 1192 | |
| 1193 | out.writeByte(opc_new); |
| 1194 | out.writeShort(cp.getClass("java/lang/NoSuchMethodError")); |
| 1195 | |
| 1196 | out.writeByte(opc_dup); |
| 1197 | |
| 1198 | code_aload(localSlot0, out); |
| 1199 | |
| 1200 | out.writeByte(opc_invokevirtual); |
| 1201 | out.writeShort(cp.getMethodRef( |
| 1202 | "java/lang/Throwable", "getMessage", "()Ljava/lang/String;")); |
| 1203 | |
| 1204 | out.writeByte(opc_invokespecial); |
| 1205 | out.writeShort(cp.getMethodRef( |
| 1206 | "java/lang/NoSuchMethodError", "<init>", "(Ljava/lang/String;)V")); |
| 1207 | |
| 1208 | out.writeByte(opc_athrow); |
| 1209 | |
| 1210 | pc = (short) minfo.code.size(); |
| 1211 | |
| 1212 | minfo.exceptionTable.add(new ExceptionTableEntry( |
| 1213 | tryBegin, tryEnd, pc, |
| 1214 | cp.getClass("java/lang/ClassNotFoundException"))); |
| 1215 | |
| 1216 | code_astore(localSlot0, out); |
| 1217 | |
| 1218 | out.writeByte(opc_new); |
| 1219 | out.writeShort(cp.getClass("java/lang/NoClassDefFoundError")); |
| 1220 | |
| 1221 | out.writeByte(opc_dup); |
| 1222 | |
| 1223 | code_aload(localSlot0, out); |
| 1224 | |
| 1225 | out.writeByte(opc_invokevirtual); |
| 1226 | out.writeShort(cp.getMethodRef( |
| 1227 | "java/lang/Throwable", "getMessage", "()Ljava/lang/String;")); |
| 1228 | |
| 1229 | out.writeByte(opc_invokespecial); |
| 1230 | out.writeShort(cp.getMethodRef( |
| 1231 | "java/lang/NoClassDefFoundError", |
| 1232 | "<init>", "(Ljava/lang/String;)V")); |
| 1233 | |
| 1234 | out.writeByte(opc_athrow); |
| 1235 | |
| 1236 | if (minfo.code.size() > 65535) { |
| 1237 | throw new IllegalArgumentException("code size limit exceeded"); |
| 1238 | } |
| 1239 | |
| 1240 | minfo.maxStack = 10; |
| 1241 | minfo.maxLocals = (short) (localSlot0 + 1); |
| 1242 | minfo.declaredExceptions = new short[0]; |
| 1243 | |
| 1244 | return minfo; |
| 1245 | } |
| 1246 | |
| 1247 | |
| 1248 | /* |
| 1249 | * =============== Code Generation Utility Methods =============== |
| 1250 | */ |
| 1251 | |
| 1252 | /* |
| 1253 | * The following methods generate code for the load or store operation |
| 1254 | * indicated by their name for the given local variable. The code is |
| 1255 | * written to the supplied stream. |
| 1256 | */ |
| 1257 | |
| 1258 | private void code_iload(int lvar, DataOutputStream out) |
| 1259 | throws IOException |
| 1260 | { |
| 1261 | codeLocalLoadStore(lvar, opc_iload, opc_iload_0, out); |
| 1262 | } |
| 1263 | |
| 1264 | private void code_lload(int lvar, DataOutputStream out) |
| 1265 | throws IOException |
| 1266 | { |
| 1267 | codeLocalLoadStore(lvar, opc_lload, opc_lload_0, out); |
| 1268 | } |
| 1269 | |
| 1270 | private void code_fload(int lvar, DataOutputStream out) |
| 1271 | throws IOException |
| 1272 | { |
| 1273 | codeLocalLoadStore(lvar, opc_fload, opc_fload_0, out); |
| 1274 | } |
| 1275 | |
| 1276 | private void code_dload(int lvar, DataOutputStream out) |
| 1277 | throws IOException |
| 1278 | { |
| 1279 | codeLocalLoadStore(lvar, opc_dload, opc_dload_0, out); |
| 1280 | } |
| 1281 | |
| 1282 | private void code_aload(int lvar, DataOutputStream out) |
| 1283 | throws IOException |
| 1284 | { |
| 1285 | codeLocalLoadStore(lvar, opc_aload, opc_aload_0, out); |
| 1286 | } |
| 1287 | |
| 1288 | // private void code_istore(int lvar, DataOutputStream out) |
| 1289 | // throws IOException |
| 1290 | // { |
| 1291 | // codeLocalLoadStore(lvar, opc_istore, opc_istore_0, out); |
| 1292 | // } |
| 1293 | |
| 1294 | // private void code_lstore(int lvar, DataOutputStream out) |
| 1295 | // throws IOException |
| 1296 | // { |
| 1297 | // codeLocalLoadStore(lvar, opc_lstore, opc_lstore_0, out); |
| 1298 | // } |
| 1299 | |
| 1300 | // private void code_fstore(int lvar, DataOutputStream out) |
| 1301 | // throws IOException |
| 1302 | // { |
| 1303 | // codeLocalLoadStore(lvar, opc_fstore, opc_fstore_0, out); |
| 1304 | // } |
| 1305 | |
| 1306 | // private void code_dstore(int lvar, DataOutputStream out) |
| 1307 | // throws IOException |
| 1308 | // { |
| 1309 | // codeLocalLoadStore(lvar, opc_dstore, opc_dstore_0, out); |
| 1310 | // } |
| 1311 | |
| 1312 | private void code_astore(int lvar, DataOutputStream out) |
| 1313 | throws IOException |
| 1314 | { |
| 1315 | codeLocalLoadStore(lvar, opc_astore, opc_astore_0, out); |
| 1316 | } |
| 1317 | |
| 1318 | /** |
| 1319 | * Generate code for a load or store instruction for the given local |
| 1320 | * variable. The code is written to the supplied stream. |
| 1321 | * |
| 1322 | * "opcode" indicates the opcode form of the desired load or store |
| 1323 | * instruction that takes an explicit local variable index, and |
| 1324 | * "opcode_0" indicates the corresponding form of the instruction |
| 1325 | * with the implicit index 0. |
| 1326 | */ |
| 1327 | private void codeLocalLoadStore(int lvar, int opcode, int opcode_0, |
| 1328 | DataOutputStream out) |
| 1329 | throws IOException |
| 1330 | { |
| 1331 | assert lvar >= 0 && lvar <= 0xFFFF; |
| 1332 | if (lvar <= 3) { |
| 1333 | out.writeByte(opcode_0 + lvar); |
| 1334 | } else if (lvar <= 0xFF) { |
| 1335 | out.writeByte(opcode); |
| 1336 | out.writeByte(lvar & 0xFF); |
| 1337 | } else { |
| 1338 | /* |
| 1339 | * Use the "wide" instruction modifier for local variable |
| 1340 | * indexes that do not fit into an unsigned byte. |
| 1341 | */ |
| 1342 | out.writeByte(opc_wide); |
| 1343 | out.writeByte(opcode); |
| 1344 | out.writeShort(lvar & 0xFFFF); |
| 1345 | } |
| 1346 | } |
| 1347 | |
| 1348 | /** |
| 1349 | * Generate code for an "ldc" instruction for the given constant pool |
| 1350 | * index (the "ldc_w" instruction is used if the index does not fit |
| 1351 | * into an unsigned byte). The code is written to the supplied stream. |
| 1352 | */ |
| 1353 | private void code_ldc(int index, DataOutputStream out) |
| 1354 | throws IOException |
| 1355 | { |
| 1356 | assert index >= 0 && index <= 0xFFFF; |
| 1357 | if (index <= 0xFF) { |
| 1358 | out.writeByte(opc_ldc); |
| 1359 | out.writeByte(index & 0xFF); |
| 1360 | } else { |
| 1361 | out.writeByte(opc_ldc_w); |
| 1362 | out.writeShort(index & 0xFFFF); |
| 1363 | } |
| 1364 | } |
| 1365 | |
| 1366 | /** |
| 1367 | * Generate code to push a constant integer value on to the operand |
| 1368 | * stack, using the "iconst_<i>", "bipush", or "sipush" instructions |
| 1369 | * depending on the size of the value. The code is written to the |
| 1370 | * supplied stream. |
| 1371 | */ |
| 1372 | private void code_ipush(int value, DataOutputStream out) |
| 1373 | throws IOException |
| 1374 | { |
| 1375 | if (value >= -1 && value <= 5) { |
| 1376 | out.writeByte(opc_iconst_0 + value); |
| 1377 | } else if (value >= Byte.MIN_VALUE && value <= Byte.MAX_VALUE) { |
| 1378 | out.writeByte(opc_bipush); |
| 1379 | out.writeByte(value & 0xFF); |
| 1380 | } else if (value >= Short.MIN_VALUE && value <= Short.MAX_VALUE) { |
| 1381 | out.writeByte(opc_sipush); |
| 1382 | out.writeShort(value & 0xFFFF); |
| 1383 | } else { |
| 1384 | throw new AssertionError(); |
| 1385 | } |
| 1386 | } |
| 1387 | |
| 1388 | /** |
| 1389 | * Generate code to invoke the Class.forName with the name of the given |
| 1390 | * class to get its Class object at runtime. The code is written to |
| 1391 | * the supplied stream. Note that the code generated by this method |
| 1392 | * may caused the checked ClassNotFoundException to be thrown. |
| 1393 | */ |
| 1394 | private void codeClassForName(Class cl, DataOutputStream out) |
| 1395 | throws IOException |
| 1396 | { |
| 1397 | code_ldc(cp.getString(cl.getName()), out); |
| 1398 | |
| 1399 | out.writeByte(opc_invokestatic); |
| 1400 | out.writeShort(cp.getMethodRef( |
| 1401 | "java/lang/Class", |
| 1402 | "forName", "(Ljava/lang/String;)Ljava/lang/Class;")); |
| 1403 | } |
| 1404 | |
| 1405 | |
| 1406 | /* |
| 1407 | * ==================== General Utility Methods ==================== |
| 1408 | */ |
| 1409 | |
| 1410 | /** |
| 1411 | * Convert a fully qualified class name that uses '.' as the package |
| 1412 | * separator, the external representation used by the Java language |
| 1413 | * and APIs, to a fully qualified class name that uses '/' as the |
| 1414 | * package separator, the representation used in the class file |
| 1415 | * format (see JVMS section 4.2). |
| 1416 | */ |
| 1417 | private static String dotToSlash(String name) { |
| 1418 | return name.replace('.', '/'); |
| 1419 | } |
| 1420 | |
| 1421 | /** |
| 1422 | * Return the "method descriptor" string for a method with the given |
| 1423 | * parameter types and return type. See JVMS section 4.3.3. |
| 1424 | */ |
| 1425 | private static String getMethodDescriptor(Class[] parameterTypes, |
| 1426 | Class returnType) |
| 1427 | { |
| 1428 | return getParameterDescriptors(parameterTypes) + |
| 1429 | ((returnType == void.class) ? "V" : getFieldType(returnType)); |
| 1430 | } |
| 1431 | |
| 1432 | /** |
| 1433 | * Return the list of "parameter descriptor" strings enclosed in |
| 1434 | * parentheses corresponding to the given parameter types (in other |
| 1435 | * words, a method descriptor without a return descriptor). This |
| 1436 | * string is useful for constructing string keys for methods without |
| 1437 | * regard to their return type. |
| 1438 | */ |
| 1439 | private static String getParameterDescriptors(Class[] parameterTypes) { |
| 1440 | StringBuilder desc = new StringBuilder("("); |
| 1441 | for (int i = 0; i < parameterTypes.length; i++) { |
| 1442 | desc.append(getFieldType(parameterTypes[i])); |
| 1443 | } |
| 1444 | desc.append(')'); |
| 1445 | return desc.toString(); |
| 1446 | } |
| 1447 | |
| 1448 | /** |
| 1449 | * Return the "field type" string for the given type, appropriate for |
| 1450 | * a field descriptor, a parameter descriptor, or a return descriptor |
| 1451 | * other than "void". See JVMS section 4.3.2. |
| 1452 | */ |
| 1453 | private static String getFieldType(Class type) { |
| 1454 | if (type.isPrimitive()) { |
| 1455 | return PrimitiveTypeInfo.get(type).baseTypeString; |
| 1456 | } else if (type.isArray()) { |
| 1457 | /* |
| 1458 | * According to JLS 20.3.2, the getName() method on Class does |
| 1459 | * return the VM type descriptor format for array classes (only); |
| 1460 | * using that should be quicker than the otherwise obvious code: |
| 1461 | * |
| 1462 | * return "[" + getTypeDescriptor(type.getComponentType()); |
| 1463 | */ |
| 1464 | return type.getName().replace('.', '/'); |
| 1465 | } else { |
| 1466 | return "L" + dotToSlash(type.getName()) + ";"; |
| 1467 | } |
| 1468 | } |
| 1469 | |
| 1470 | /** |
| 1471 | * Returns a human-readable string representing the signature of a |
| 1472 | * method with the given name and parameter types. |
| 1473 | */ |
| 1474 | private static String getFriendlyMethodSignature(String name, |
| 1475 | Class[] parameterTypes) |
| 1476 | { |
| 1477 | StringBuilder sig = new StringBuilder(name); |
| 1478 | sig.append('('); |
| 1479 | for (int i = 0; i < parameterTypes.length; i++) { |
| 1480 | if (i > 0) { |
| 1481 | sig.append(','); |
| 1482 | } |
| 1483 | Class parameterType = parameterTypes[i]; |
| 1484 | int dimensions = 0; |
| 1485 | while (parameterType.isArray()) { |
| 1486 | parameterType = parameterType.getComponentType(); |
| 1487 | dimensions++; |
| 1488 | } |
| 1489 | sig.append(parameterType.getName()); |
| 1490 | while (dimensions-- > 0) { |
| 1491 | sig.append("[]"); |
| 1492 | } |
| 1493 | } |
| 1494 | sig.append(')'); |
| 1495 | return sig.toString(); |
| 1496 | } |
| 1497 | |
| 1498 | /** |
| 1499 | * Return the number of abstract "words", or consecutive local variable |
| 1500 | * indexes, required to contain a value of the given type. See JVMS |
| 1501 | * section 3.6.1. |
| 1502 | * |
| 1503 | * Note that the original version of the JVMS contained a definition of |
| 1504 | * this abstract notion of a "word" in section 3.4, but that definition |
| 1505 | * was removed for the second edition. |
| 1506 | */ |
| 1507 | private static int getWordsPerType(Class type) { |
| 1508 | if (type == long.class || type == double.class) { |
| 1509 | return 2; |
| 1510 | } else { |
| 1511 | return 1; |
| 1512 | } |
| 1513 | } |
| 1514 | |
| 1515 | /** |
| 1516 | * Add to the given list all of the types in the "from" array that |
| 1517 | * are not already contained in the list and are assignable to at |
| 1518 | * least one of the types in the "with" array. |
| 1519 | * |
| 1520 | * This method is useful for computing the greatest common set of |
| 1521 | * declared exceptions from duplicate methods inherited from |
| 1522 | * different interfaces. |
| 1523 | */ |
| 1524 | private static void collectCompatibleTypes(Class[] from, Class[] with, |
| 1525 | List<Class> list) |
| 1526 | { |
| 1527 | for (int i = 0; i < from.length; i++) { |
| 1528 | if (!list.contains(from[i])) { |
| 1529 | for (int j = 0; j < with.length; j++) { |
| 1530 | if (with[j].isAssignableFrom(from[i])) { |
| 1531 | list.add(from[i]); |
| 1532 | break; |
| 1533 | } |
| 1534 | } |
| 1535 | } |
| 1536 | } |
| 1537 | } |
| 1538 | |
| 1539 | /** |
| 1540 | * Given the exceptions declared in the throws clause of a proxy method, |
| 1541 | * compute the exceptions that need to be caught from the invocation |
| 1542 | * handler's invoke method and rethrown intact in the method's |
| 1543 | * implementation before catching other Throwables and wrapping them |
| 1544 | * in UndeclaredThrowableExceptions. |
| 1545 | * |
| 1546 | * The exceptions to be caught are returned in a List object. Each |
| 1547 | * exception in the returned list is guaranteed to not be a subclass of |
| 1548 | * any of the other exceptions in the list, so the catch blocks for |
| 1549 | * these exceptions may be generated in any order relative to each other. |
| 1550 | * |
| 1551 | * Error and RuntimeException are each always contained by the returned |
| 1552 | * list (if none of their superclasses are contained), since those |
| 1553 | * unchecked exceptions should always be rethrown intact, and thus their |
| 1554 | * subclasses will never appear in the returned list. |
| 1555 | * |
| 1556 | * The returned List will be empty if java.lang.Throwable is in the |
| 1557 | * given list of declared exceptions, indicating that no exceptions |
| 1558 | * need to be caught. |
| 1559 | */ |
| 1560 | private static List<Class> computeUniqueCatchList(Class[] exceptions) { |
| 1561 | List<Class> uniqueList = new ArrayList<Class>(); |
| 1562 | // unique exceptions to catch |
| 1563 | |
| 1564 | uniqueList.add(Error.class); // always catch/rethrow these |
| 1565 | uniqueList.add(RuntimeException.class); |
| 1566 | |
| 1567 | nextException: |
| 1568 | for (int i = 0; i < exceptions.length; i++) { |
| 1569 | Class ex = exceptions[i]; |
| 1570 | if (ex.isAssignableFrom(Throwable.class)) { |
| 1571 | /* |
| 1572 | * If Throwable is declared to be thrown by the proxy method, |
| 1573 | * then no catch blocks are necessary, because the invoke |
| 1574 | * can, at most, throw Throwable anyway. |
| 1575 | */ |
| 1576 | uniqueList.clear(); |
| 1577 | break; |
| 1578 | } else if (!Throwable.class.isAssignableFrom(ex)) { |
| 1579 | /* |
| 1580 | * Ignore types that cannot be thrown by the invoke method. |
| 1581 | */ |
| 1582 | continue; |
| 1583 | } |
| 1584 | /* |
| 1585 | * Compare this exception against the current list of |
| 1586 | * exceptions that need to be caught: |
| 1587 | */ |
| 1588 | for (int j = 0; j < uniqueList.size();) { |
| 1589 | Class ex2 = uniqueList.get(j); |
| 1590 | if (ex2.isAssignableFrom(ex)) { |
| 1591 | /* |
| 1592 | * if a superclass of this exception is already on |
| 1593 | * the list to catch, then ignore this one and continue; |
| 1594 | */ |
| 1595 | continue nextException; |
| 1596 | } else if (ex.isAssignableFrom(ex2)) { |
| 1597 | /* |
| 1598 | * if a subclass of this exception is on the list |
| 1599 | * to catch, then remove it; |
| 1600 | */ |
| 1601 | uniqueList.remove(j); |
| 1602 | } else { |
| 1603 | j++; // else continue comparing. |
| 1604 | } |
| 1605 | } |
| 1606 | // This exception is unique (so far): add it to the list to catch. |
| 1607 | uniqueList.add(ex); |
| 1608 | } |
| 1609 | return uniqueList; |
| 1610 | } |
| 1611 | |
| 1612 | /** |
| 1613 | * A PrimitiveTypeInfo object contains assorted information about |
| 1614 | * a primitive type in its public fields. The struct for a particular |
| 1615 | * primitive type can be obtained using the static "get" method. |
| 1616 | */ |
| 1617 | private static class PrimitiveTypeInfo { |
| 1618 | |
| 1619 | /** "base type" used in various descriptors (see JVMS section 4.3.2) */ |
| 1620 | public String baseTypeString; |
| 1621 | |
| 1622 | /** name of corresponding wrapper class */ |
| 1623 | public String wrapperClassName; |
| 1624 | |
| 1625 | /** method descriptor for wrapper class "valueOf" factory method */ |
| 1626 | public String wrapperValueOfDesc; |
| 1627 | |
| 1628 | /** name of wrapper class method for retrieving primitive value */ |
| 1629 | public String unwrapMethodName; |
| 1630 | |
| 1631 | /** descriptor of same method */ |
| 1632 | public String unwrapMethodDesc; |
| 1633 | |
| 1634 | private static Map<Class,PrimitiveTypeInfo> table = |
| 1635 | new HashMap<Class,PrimitiveTypeInfo>(); |
| 1636 | static { |
| 1637 | add(byte.class, Byte.class); |
| 1638 | add(char.class, Character.class); |
| 1639 | add(double.class, Double.class); |
| 1640 | add(float.class, Float.class); |
| 1641 | add(int.class, Integer.class); |
| 1642 | add(long.class, Long.class); |
| 1643 | add(short.class, Short.class); |
| 1644 | add(boolean.class, Boolean.class); |
| 1645 | } |
| 1646 | |
| 1647 | private static void add(Class primitiveClass, Class wrapperClass) { |
| 1648 | table.put(primitiveClass, |
| 1649 | new PrimitiveTypeInfo(primitiveClass, wrapperClass)); |
| 1650 | } |
| 1651 | |
| 1652 | private PrimitiveTypeInfo(Class primitiveClass, Class wrapperClass) { |
| 1653 | assert primitiveClass.isPrimitive(); |
| 1654 | |
| 1655 | baseTypeString = |
| 1656 | Array.newInstance(primitiveClass, 0) |
| 1657 | .getClass().getName().substring(1); |
| 1658 | wrapperClassName = dotToSlash(wrapperClass.getName()); |
| 1659 | wrapperValueOfDesc = |
| 1660 | "(" + baseTypeString + ")L" + wrapperClassName + ";"; |
| 1661 | unwrapMethodName = primitiveClass.getName() + "Value"; |
| 1662 | unwrapMethodDesc = "()" + baseTypeString; |
| 1663 | } |
| 1664 | |
| 1665 | public static PrimitiveTypeInfo get(Class cl) { |
| 1666 | return table.get(cl); |
| 1667 | } |
| 1668 | } |
| 1669 | |
| 1670 | |
| 1671 | /** |
| 1672 | * A ConstantPool object represents the constant pool of a class file |
| 1673 | * being generated. This representation of a constant pool is designed |
| 1674 | * specifically for use by ProxyGenerator; in particular, it assumes |
| 1675 | * that constant pool entries will not need to be resorted (for example, |
| 1676 | * by their type, as the Java compiler does), so that the final index |
| 1677 | * value can be assigned and used when an entry is first created. |
| 1678 | * |
| 1679 | * Note that new entries cannot be created after the constant pool has |
| 1680 | * been written to a class file. To prevent such logic errors, a |
| 1681 | * ConstantPool instance can be marked "read only", so that further |
| 1682 | * attempts to add new entries will fail with a runtime exception. |
| 1683 | * |
| 1684 | * See JVMS section 4.4 for more information about the constant pool |
| 1685 | * of a class file. |
| 1686 | */ |
| 1687 | private static class ConstantPool { |
| 1688 | |
| 1689 | /** |
| 1690 | * list of constant pool entries, in constant pool index order. |
| 1691 | * |
| 1692 | * This list is used when writing the constant pool to a stream |
| 1693 | * and for assigning the next index value. Note that element 0 |
| 1694 | * of this list corresponds to constant pool index 1. |
| 1695 | */ |
| 1696 | private List<Entry> pool = new ArrayList<Entry>(32); |
| 1697 | |
| 1698 | /** |
| 1699 | * maps constant pool data of all types to constant pool indexes. |
| 1700 | * |
| 1701 | * This map is used to look up the index of an existing entry for |
| 1702 | * values of all types. |
| 1703 | */ |
| 1704 | private Map<Object,Short> map = new HashMap<Object,Short>(16); |
| 1705 | |
| 1706 | /** true if no new constant pool entries may be added */ |
| 1707 | private boolean readOnly = false; |
| 1708 | |
| 1709 | /** |
| 1710 | * Get or assign the index for a CONSTANT_Utf8 entry. |
| 1711 | */ |
| 1712 | public short getUtf8(String s) { |
| 1713 | if (s == null) { |
| 1714 | throw new NullPointerException(); |
| 1715 | } |
| 1716 | return getValue(s); |
| 1717 | } |
| 1718 | |
| 1719 | /** |
| 1720 | * Get or assign the index for a CONSTANT_Integer entry. |
| 1721 | */ |
| 1722 | public short getInteger(int i) { |
| 1723 | return getValue(new Integer(i)); |
| 1724 | } |
| 1725 | |
| 1726 | /** |
| 1727 | * Get or assign the index for a CONSTANT_Float entry. |
| 1728 | */ |
| 1729 | public short getFloat(float f) { |
| 1730 | return getValue(new Float(f)); |
| 1731 | } |
| 1732 | |
| 1733 | /** |
| 1734 | * Get or assign the index for a CONSTANT_Class entry. |
| 1735 | */ |
| 1736 | public short getClass(String name) { |
| 1737 | short utf8Index = getUtf8(name); |
| 1738 | return getIndirect(new IndirectEntry( |
| 1739 | CONSTANT_CLASS, utf8Index)); |
| 1740 | } |
| 1741 | |
| 1742 | /** |
| 1743 | * Get or assign the index for a CONSTANT_String entry. |
| 1744 | */ |
| 1745 | public short getString(String s) { |
| 1746 | short utf8Index = getUtf8(s); |
| 1747 | return getIndirect(new IndirectEntry( |
| 1748 | CONSTANT_STRING, utf8Index)); |
| 1749 | } |
| 1750 | |
| 1751 | /** |
| 1752 | * Get or assign the index for a CONSTANT_FieldRef entry. |
| 1753 | */ |
| 1754 | public short getFieldRef(String className, |
| 1755 | String name, String descriptor) |
| 1756 | { |
| 1757 | short classIndex = getClass(className); |
| 1758 | short nameAndTypeIndex = getNameAndType(name, descriptor); |
| 1759 | return getIndirect(new IndirectEntry( |
| 1760 | CONSTANT_FIELD, classIndex, nameAndTypeIndex)); |
| 1761 | } |
| 1762 | |
| 1763 | /** |
| 1764 | * Get or assign the index for a CONSTANT_MethodRef entry. |
| 1765 | */ |
| 1766 | public short getMethodRef(String className, |
| 1767 | String name, String descriptor) |
| 1768 | { |
| 1769 | short classIndex = getClass(className); |
| 1770 | short nameAndTypeIndex = getNameAndType(name, descriptor); |
| 1771 | return getIndirect(new IndirectEntry( |
| 1772 | CONSTANT_METHOD, classIndex, nameAndTypeIndex)); |
| 1773 | } |
| 1774 | |
| 1775 | /** |
| 1776 | * Get or assign the index for a CONSTANT_InterfaceMethodRef entry. |
| 1777 | */ |
| 1778 | public short getInterfaceMethodRef(String className, String name, |
| 1779 | String descriptor) |
| 1780 | { |
| 1781 | short classIndex = getClass(className); |
| 1782 | short nameAndTypeIndex = getNameAndType(name, descriptor); |
| 1783 | return getIndirect(new IndirectEntry( |
| 1784 | CONSTANT_INTERFACEMETHOD, classIndex, nameAndTypeIndex)); |
| 1785 | } |
| 1786 | |
| 1787 | /** |
| 1788 | * Get or assign the index for a CONSTANT_NameAndType entry. |
| 1789 | */ |
| 1790 | public short getNameAndType(String name, String descriptor) { |
| 1791 | short nameIndex = getUtf8(name); |
| 1792 | short descriptorIndex = getUtf8(descriptor); |
| 1793 | return getIndirect(new IndirectEntry( |
| 1794 | CONSTANT_NAMEANDTYPE, nameIndex, descriptorIndex)); |
| 1795 | } |
| 1796 | |
| 1797 | /** |
| 1798 | * Set this ConstantPool instance to be "read only". |
| 1799 | * |
| 1800 | * After this method has been called, further requests to get |
| 1801 | * an index for a non-existent entry will cause an InternalError |
| 1802 | * to be thrown instead of creating of the entry. |
| 1803 | */ |
| 1804 | public void setReadOnly() { |
| 1805 | readOnly = true; |
| 1806 | } |
| 1807 | |
| 1808 | /** |
| 1809 | * Write this constant pool to a stream as part of |
| 1810 | * the class file format. |
| 1811 | * |
| 1812 | * This consists of writing the "constant_pool_count" and |
| 1813 | * "constant_pool[]" items of the "ClassFile" structure, as |
| 1814 | * described in JVMS section 4.1. |
| 1815 | */ |
| 1816 | public void write(OutputStream out) throws IOException { |
| 1817 | DataOutputStream dataOut = new DataOutputStream(out); |
| 1818 | |
| 1819 | // constant_pool_count: number of entries plus one |
| 1820 | dataOut.writeShort(pool.size() + 1); |
| 1821 | |
| 1822 | for (Entry e : pool) { |
| 1823 | e.write(dataOut); |
| 1824 | } |
| 1825 | } |
| 1826 | |
| 1827 | /** |
| 1828 | * Add a new constant pool entry and return its index. |
| 1829 | */ |
| 1830 | private short addEntry(Entry entry) { |
| 1831 | pool.add(entry); |
| 1832 | /* |
| 1833 | * Note that this way of determining the index of the |
| 1834 | * added entry is wrong if this pool supports |
| 1835 | * CONSTANT_Long or CONSTANT_Double entries. |
| 1836 | */ |
| 1837 | if (pool.size() >= 65535) { |
| 1838 | throw new IllegalArgumentException( |
| 1839 | "constant pool size limit exceeded"); |
| 1840 | } |
| 1841 | return (short) pool.size(); |
| 1842 | } |
| 1843 | |
| 1844 | /** |
| 1845 | * Get or assign the index for an entry of a type that contains |
| 1846 | * a direct value. The type of the given object determines the |
| 1847 | * type of the desired entry as follows: |
| 1848 | * |
| 1849 | * java.lang.String CONSTANT_Utf8 |
| 1850 | * java.lang.Integer CONSTANT_Integer |
| 1851 | * java.lang.Float CONSTANT_Float |
| 1852 | * java.lang.Long CONSTANT_Long |
| 1853 | * java.lang.Double CONSTANT_DOUBLE |
| 1854 | */ |
| 1855 | private short getValue(Object key) { |
| 1856 | Short index = map.get(key); |
| 1857 | if (index != null) { |
| 1858 | return index.shortValue(); |
| 1859 | } else { |
| 1860 | if (readOnly) { |
| 1861 | throw new InternalError( |
| 1862 | "late constant pool addition: " + key); |
| 1863 | } |
| 1864 | short i = addEntry(new ValueEntry(key)); |
| 1865 | map.put(key, new Short(i)); |
| 1866 | return i; |
| 1867 | } |
| 1868 | } |
| 1869 | |
| 1870 | /** |
| 1871 | * Get or assign the index for an entry of a type that contains |
| 1872 | * references to other constant pool entries. |
| 1873 | */ |
| 1874 | private short getIndirect(IndirectEntry e) { |
| 1875 | Short index = map.get(e); |
| 1876 | if (index != null) { |
| 1877 | return index.shortValue(); |
| 1878 | } else { |
| 1879 | if (readOnly) { |
| 1880 | throw new InternalError("late constant pool addition"); |
| 1881 | } |
| 1882 | short i = addEntry(e); |
| 1883 | map.put(e, new Short(i)); |
| 1884 | return i; |
| 1885 | } |
| 1886 | } |
| 1887 | |
| 1888 | /** |
| 1889 | * Entry is the abstact superclass of all constant pool entry types |
| 1890 | * that can be stored in the "pool" list; its purpose is to define a |
| 1891 | * common method for writing constant pool entries to a class file. |
| 1892 | */ |
| 1893 | private static abstract class Entry { |
| 1894 | public abstract void write(DataOutputStream out) |
| 1895 | throws IOException; |
| 1896 | } |
| 1897 | |
| 1898 | /** |
| 1899 | * ValueEntry represents a constant pool entry of a type that |
| 1900 | * contains a direct value (see the comments for the "getValue" |
| 1901 | * method for a list of such types). |
| 1902 | * |
| 1903 | * ValueEntry objects are not used as keys for their entries in the |
| 1904 | * Map "map", so no useful hashCode or equals methods are defined. |
| 1905 | */ |
| 1906 | private static class ValueEntry extends Entry { |
| 1907 | private Object value; |
| 1908 | |
| 1909 | public ValueEntry(Object value) { |
| 1910 | this.value = value; |
| 1911 | } |
| 1912 | |
| 1913 | public void write(DataOutputStream out) throws IOException { |
| 1914 | if (value instanceof String) { |
| 1915 | out.writeByte(CONSTANT_UTF8); |
| 1916 | out.writeUTF((String) value); |
| 1917 | } else if (value instanceof Integer) { |
| 1918 | out.writeByte(CONSTANT_INTEGER); |
| 1919 | out.writeInt(((Integer) value).intValue()); |
| 1920 | } else if (value instanceof Float) { |
| 1921 | out.writeByte(CONSTANT_FLOAT); |
| 1922 | out.writeFloat(((Float) value).floatValue()); |
| 1923 | } else if (value instanceof Long) { |
| 1924 | out.writeByte(CONSTANT_LONG); |
| 1925 | out.writeLong(((Long) value).longValue()); |
| 1926 | } else if (value instanceof Double) { |
| 1927 | out.writeDouble(CONSTANT_DOUBLE); |
| 1928 | out.writeDouble(((Double) value).doubleValue()); |
| 1929 | } else { |
| 1930 | throw new InternalError("bogus value entry: " + value); |
| 1931 | } |
| 1932 | } |
| 1933 | } |
| 1934 | |
| 1935 | /** |
| 1936 | * IndirectEntry represents a constant pool entry of a type that |
| 1937 | * references other constant pool entries, i.e., the following types: |
| 1938 | * |
| 1939 | * CONSTANT_Class, CONSTANT_String, CONSTANT_Fieldref, |
| 1940 | * CONSTANT_Methodref, CONSTANT_InterfaceMethodref, and |
| 1941 | * CONSTANT_NameAndType. |
| 1942 | * |
| 1943 | * Each of these entry types contains either one or two indexes of |
| 1944 | * other constant pool entries. |
| 1945 | * |
| 1946 | * IndirectEntry objects are used as the keys for their entries in |
| 1947 | * the Map "map", so the hashCode and equals methods are overridden |
| 1948 | * to allow matching. |
| 1949 | */ |
| 1950 | private static class IndirectEntry extends Entry { |
| 1951 | private int tag; |
| 1952 | private short index0; |
| 1953 | private short index1; |
| 1954 | |
| 1955 | /** |
| 1956 | * Construct an IndirectEntry for a constant pool entry type |
| 1957 | * that contains one index of another entry. |
| 1958 | */ |
| 1959 | public IndirectEntry(int tag, short index) { |
| 1960 | this.tag = tag; |
| 1961 | this.index0 = index; |
| 1962 | this.index1 = 0; |
| 1963 | } |
| 1964 | |
| 1965 | /** |
| 1966 | * Construct an IndirectEntry for a constant pool entry type |
| 1967 | * that contains two indexes for other entries. |
| 1968 | */ |
| 1969 | public IndirectEntry(int tag, short index0, short index1) { |
| 1970 | this.tag = tag; |
| 1971 | this.index0 = index0; |
| 1972 | this.index1 = index1; |
| 1973 | } |
| 1974 | |
| 1975 | public void write(DataOutputStream out) throws IOException { |
| 1976 | out.writeByte(tag); |
| 1977 | out.writeShort(index0); |
| 1978 | /* |
| 1979 | * If this entry type contains two indexes, write |
| 1980 | * out the second, too. |
| 1981 | */ |
| 1982 | if (tag == CONSTANT_FIELD || |
| 1983 | tag == CONSTANT_METHOD || |
| 1984 | tag == CONSTANT_INTERFACEMETHOD || |
| 1985 | tag == CONSTANT_NAMEANDTYPE) |
| 1986 | { |
| 1987 | out.writeShort(index1); |
| 1988 | } |
| 1989 | } |
| 1990 | |
| 1991 | public int hashCode() { |
| 1992 | return tag + index0 + index1; |
| 1993 | } |
| 1994 | |
| 1995 | public boolean equals(Object obj) { |
| 1996 | if (obj instanceof IndirectEntry) { |
| 1997 | IndirectEntry other = (IndirectEntry) obj; |
| 1998 | if (tag == other.tag && |
| 1999 | index0 == other.index0 && index1 == other.index1) |
| 2000 | { |
| 2001 | return true; |
| 2002 | } |
| 2003 | } |
| 2004 | return false; |
| 2005 | } |
| 2006 | } |
| 2007 | } |
| 2008 | } |