J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1994-2003 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.tools.java; |
| 27 | |
| 28 | import java.util.Hashtable; |
| 29 | |
| 30 | /** |
| 31 | * This class represents an Java Type.<p> |
| 32 | * |
| 33 | * It encapsulates an Java type signature and it provides |
| 34 | * quick access to the components of the type. Note that |
| 35 | * all types are hashed into a hashtable (typeHash), that |
| 36 | * means that each distinct type is only allocated once, |
| 37 | * saving space and making equality checks cheap.<p> |
| 38 | * |
| 39 | * For simple types use the constants defined in this class. |
| 40 | * (Type.tInt, Type.tShort, ...). To create complex types use |
| 41 | * the static methods Type.tArray, Type.tMethod or Type.tClass. |
| 42 | * |
| 43 | * For classes, arrays and method types a sub class of class |
| 44 | * type is created which defines the extra type components. |
| 45 | * |
| 46 | * WARNING: The contents of this source file are not part of any |
| 47 | * supported API. Code that depends on them does so at its own risk: |
| 48 | * they are subject to change or removal without notice. |
| 49 | * |
| 50 | * @see ArrayType |
| 51 | * @see ClassType |
| 52 | * @see MethodType |
| 53 | * @author Arthur van Hoff |
| 54 | */ |
| 55 | public |
| 56 | class Type implements Constants { |
| 57 | /** |
| 58 | * This hashtable is used to cache types |
| 59 | */ |
| 60 | private static final Hashtable typeHash = new Hashtable(231); |
| 61 | |
| 62 | /** |
| 63 | * The TypeCode of this type. The value of this field is one |
| 64 | * of the TC_* contant values defined in Constants. |
| 65 | * @see Constants |
| 66 | */ |
| 67 | protected int typeCode; |
| 68 | |
| 69 | /** |
| 70 | * The TypeSignature of this type. This type signature is |
| 71 | * equivalent to the runtime type signatures used by the |
| 72 | * interpreter. |
| 73 | */ |
| 74 | protected String typeSig; |
| 75 | |
| 76 | /* |
| 77 | * Predefined types. |
| 78 | */ |
| 79 | public static final Type noArgs[] = new Type[0]; |
| 80 | public static final Type tError = new Type(TC_ERROR, "?"); |
| 81 | public static final Type tPackage = new Type(TC_ERROR, "."); |
| 82 | public static final Type tNull = new Type(TC_NULL, "*"); |
| 83 | public static final Type tVoid = new Type(TC_VOID, SIG_VOID); |
| 84 | public static final Type tBoolean = new Type(TC_BOOLEAN, SIG_BOOLEAN); |
| 85 | public static final Type tByte = new Type(TC_BYTE, SIG_BYTE); |
| 86 | public static final Type tChar = new Type(TC_CHAR, SIG_CHAR); |
| 87 | public static final Type tShort = new Type(TC_SHORT, SIG_SHORT); |
| 88 | public static final Type tInt = new Type(TC_INT, SIG_INT); |
| 89 | public static final Type tFloat = new Type(TC_FLOAT, SIG_FLOAT); |
| 90 | public static final Type tLong = new Type(TC_LONG, SIG_LONG); |
| 91 | public static final Type tDouble = new Type(TC_DOUBLE, SIG_DOUBLE); |
| 92 | public static final Type tObject = Type.tClass(idJavaLangObject); |
| 93 | public static final Type tClassDesc = Type.tClass(idJavaLangClass); |
| 94 | public static final Type tString = Type.tClass(idJavaLangString); |
| 95 | public static final Type tCloneable = Type.tClass(idJavaLangCloneable); |
| 96 | public static final Type tSerializable = Type.tClass(idJavaIoSerializable); |
| 97 | |
| 98 | /** |
| 99 | * Create a type given a typecode and a type signature. |
| 100 | */ |
| 101 | protected Type(int typeCode, String typeSig) { |
| 102 | this.typeCode = typeCode; |
| 103 | this.typeSig = typeSig; |
| 104 | typeHash.put(typeSig, this); |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * Return the Java type signature. |
| 109 | */ |
| 110 | public final String getTypeSignature() { |
| 111 | return typeSig; |
| 112 | } |
| 113 | |
| 114 | /** |
| 115 | * Return the type code. |
| 116 | */ |
| 117 | public final int getTypeCode() { |
| 118 | return typeCode; |
| 119 | } |
| 120 | |
| 121 | /** |
| 122 | * Return the type mask. The bits in this mask correspond |
| 123 | * to the TM_* constants defined in Constants. Only one bit |
| 124 | * is set at a type. |
| 125 | * @see Constants |
| 126 | */ |
| 127 | public final int getTypeMask() { |
| 128 | return 1 << typeCode; |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Check for a certain type. |
| 133 | */ |
| 134 | public final boolean isType(int tc) { |
| 135 | return typeCode == tc; |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * Check to see if this is the bogus type "array of void" |
| 140 | * |
| 141 | * Although this highly degenerate "type" is not constructable from |
| 142 | * the grammar, the Parser accepts it. Rather than monkey with the |
| 143 | * Parser, we check for the bogus type at specific points and give |
| 144 | * a nice error. |
| 145 | */ |
| 146 | public boolean isVoidArray() { |
| 147 | // a void type is not a void array. |
| 148 | if (!isType(TC_ARRAY)) { |
| 149 | return false; |
| 150 | } |
| 151 | // If this is an array, find out what its element type is. |
| 152 | Type type = this; |
| 153 | while (type.isType(TC_ARRAY)) |
| 154 | type = type.getElementType(); |
| 155 | |
| 156 | return type.isType(TC_VOID); |
| 157 | } |
| 158 | |
| 159 | |
| 160 | /** |
| 161 | * Check for a certain set of types. |
| 162 | */ |
| 163 | public final boolean inMask(int tm) { |
| 164 | return ((1 << typeCode) & tm) != 0; |
| 165 | } |
| 166 | |
| 167 | /** |
| 168 | * Create an array type. |
| 169 | */ |
| 170 | public static synchronized Type tArray(Type elem) { |
| 171 | String sig = new String(SIG_ARRAY + elem.getTypeSignature()); |
| 172 | Type t = (Type)typeHash.get(sig); |
| 173 | if (t == null) { |
| 174 | t = new ArrayType(sig, elem); |
| 175 | } |
| 176 | return t; |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * Return the element type of an array type. Only works |
| 181 | * for array types. |
| 182 | */ |
| 183 | public Type getElementType() { |
| 184 | throw new CompilerError("getElementType"); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * Return the array dimension. Only works for |
| 189 | * array types. |
| 190 | */ |
| 191 | public int getArrayDimension() { |
| 192 | return 0; |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * Create a class type. |
| 197 | * @arg className the fully qualified class name |
| 198 | */ |
| 199 | public static synchronized Type tClass(Identifier className) { |
| 200 | if (className.isInner()) { |
| 201 | Type t = tClass(mangleInnerType(className)); |
| 202 | if (t.getClassName() != className) |
| 203 | // Somebody got here first with a mangled name. |
| 204 | // (Perhaps it came from a binary.) |
| 205 | changeClassName(t.getClassName(), className); |
| 206 | return t; |
| 207 | } |
| 208 | // see if we've cached the object in the Identifier |
| 209 | if (className.typeObject != null) { |
| 210 | return className.typeObject; |
| 211 | } |
| 212 | String sig = |
| 213 | new String(SIG_CLASS + |
| 214 | className.toString().replace('.', SIGC_PACKAGE) + |
| 215 | SIG_ENDCLASS); |
| 216 | Type t = (Type)typeHash.get(sig); |
| 217 | if (t == null) { |
| 218 | t = new ClassType(sig, className); |
| 219 | } |
| 220 | |
| 221 | className.typeObject = t; // cache the Type object in the Identifier |
| 222 | return t; |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * Return the ClassName. Only works on class types. |
| 227 | */ |
| 228 | public Identifier getClassName() { |
| 229 | throw new CompilerError("getClassName:" + this); |
| 230 | } |
| 231 | |
| 232 | /** |
| 233 | * Given an inner identifier, return the non-inner, mangled |
| 234 | * representation used to manage signatures. |
| 235 | * |
| 236 | * Note: It is changed to 'public' for Jcov file generation. |
| 237 | * (see Assembler.java) |
| 238 | */ |
| 239 | |
| 240 | public static Identifier mangleInnerType(Identifier className) { |
| 241 | // Map "pkg.Foo. Bar" to "pkg.Foo$Bar". |
| 242 | if (!className.isInner()) return className; |
| 243 | Identifier mname = Identifier.lookup( |
| 244 | className.getFlatName().toString(). |
| 245 | replace('.', SIGC_INNERCLASS) ); |
| 246 | if (mname.isInner()) throw new CompilerError("mangle "+mname); |
| 247 | return Identifier.lookup(className.getQualifier(), mname); |
| 248 | } |
| 249 | |
| 250 | /** |
| 251 | * We have learned that a signature means something other |
| 252 | * that what we thought it meant. Live with it: Change all |
| 253 | * affected data structures to reflect the new name of the old type. |
| 254 | * <p> |
| 255 | * (This is necessary because of an ambiguity between the |
| 256 | * low-level signatures of inner types and their manglings. |
| 257 | * Note that the latter are also valid class names.) |
| 258 | */ |
| 259 | static void changeClassName(Identifier oldName, Identifier newName) { |
| 260 | // Note: If we are upgrading "pkg.Foo$Bar" to "pkg.Foo. Bar", |
| 261 | // we assume someone else will come along and deal with any types |
| 262 | // inner within Bar. So, there's only one change to make. |
| 263 | ((ClassType)Type.tClass(oldName)).className = newName; |
| 264 | } |
| 265 | |
| 266 | /** |
| 267 | * Create a method type with no arguments. |
| 268 | */ |
| 269 | public static synchronized Type tMethod(Type ret) { |
| 270 | return tMethod(ret, noArgs); |
| 271 | } |
| 272 | |
| 273 | /** |
| 274 | * Create a method type with arguments. |
| 275 | */ |
| 276 | public static synchronized Type tMethod(Type returnType, Type argTypes[]) { |
| 277 | StringBuffer buf = new StringBuffer(); |
| 278 | buf.append(SIG_METHOD); |
| 279 | for (int i = 0 ; i < argTypes.length ; i++) { |
| 280 | buf.append(argTypes[i].getTypeSignature()); |
| 281 | } |
| 282 | buf.append(SIG_ENDMETHOD); |
| 283 | buf.append(returnType.getTypeSignature()); |
| 284 | |
| 285 | String sig = buf.toString(); |
| 286 | Type t = (Type)typeHash.get(sig); |
| 287 | if (t == null) { |
| 288 | t = new MethodType(sig, returnType, argTypes); |
| 289 | } |
| 290 | return t; |
| 291 | } |
| 292 | |
| 293 | /** |
| 294 | * Return the return type. Only works for method types. |
| 295 | */ |
| 296 | public Type getReturnType() { |
| 297 | throw new CompilerError("getReturnType"); |
| 298 | } |
| 299 | |
| 300 | /** |
| 301 | * Return the argument types. Only works for method types. |
| 302 | */ |
| 303 | public Type getArgumentTypes()[] { |
| 304 | throw new CompilerError("getArgumentTypes"); |
| 305 | } |
| 306 | |
| 307 | /** |
| 308 | * Create a Type from an Java type signature. |
| 309 | * @exception CompilerError invalid type signature. |
| 310 | */ |
| 311 | public static synchronized Type tType(String sig) { |
| 312 | Type t = (Type)typeHash.get(sig); |
| 313 | if (t != null) { |
| 314 | return t; |
| 315 | } |
| 316 | |
| 317 | switch (sig.charAt(0)) { |
| 318 | case SIGC_ARRAY: |
| 319 | return Type.tArray(tType(sig.substring(1))); |
| 320 | |
| 321 | case SIGC_CLASS: |
| 322 | return Type.tClass(Identifier.lookup(sig.substring(1, sig.length() - 1).replace(SIGC_PACKAGE, '.'))); |
| 323 | |
| 324 | case SIGC_METHOD: { |
| 325 | Type argv[] = new Type[8]; |
| 326 | int argc = 0; |
| 327 | int i, j; |
| 328 | |
| 329 | for (i = 1 ; sig.charAt(i) != SIGC_ENDMETHOD ; i = j) { |
| 330 | for (j = i ; sig.charAt(j) == SIGC_ARRAY ; j++); |
| 331 | if (sig.charAt(j++) == SIGC_CLASS) { |
| 332 | while (sig.charAt(j++) != SIGC_ENDCLASS); |
| 333 | } |
| 334 | if (argc == argv.length) { |
| 335 | Type newargv[] = new Type[argc * 2]; |
| 336 | System.arraycopy(argv, 0, newargv, 0, argc); |
| 337 | argv = newargv; |
| 338 | } |
| 339 | argv[argc++] = tType(sig.substring(i, j)); |
| 340 | } |
| 341 | |
| 342 | Type argtypes[] = new Type[argc]; |
| 343 | System.arraycopy(argv, 0, argtypes, 0, argc); |
| 344 | return Type.tMethod(tType(sig.substring(i + 1)), argtypes); |
| 345 | } |
| 346 | } |
| 347 | |
| 348 | throw new CompilerError("invalid TypeSignature:" + sig); |
| 349 | } |
| 350 | |
| 351 | /** |
| 352 | * Check if the type arguments are the same. |
| 353 | * @return true if both types are method types and the |
| 354 | * argument types are identical. |
| 355 | */ |
| 356 | public boolean equalArguments(Type t) { |
| 357 | return false; |
| 358 | } |
| 359 | |
| 360 | /** |
| 361 | * Return the amount of space this type takes up on the |
| 362 | * Java operand stack. For a method this is equal to the |
| 363 | * total space taken up by the arguments. |
| 364 | */ |
| 365 | public int stackSize() { |
| 366 | switch (typeCode) { |
| 367 | case TC_ERROR: |
| 368 | case TC_VOID: |
| 369 | return 0; |
| 370 | case TC_BOOLEAN: |
| 371 | case TC_BYTE: |
| 372 | case TC_SHORT: |
| 373 | case TC_CHAR: |
| 374 | case TC_INT: |
| 375 | case TC_FLOAT: |
| 376 | case TC_ARRAY: |
| 377 | case TC_CLASS: |
| 378 | return 1; |
| 379 | case TC_LONG: |
| 380 | case TC_DOUBLE: |
| 381 | return 2; |
| 382 | } |
| 383 | throw new CompilerError("stackSize " + toString()); |
| 384 | } |
| 385 | |
| 386 | /** |
| 387 | * Return the type code offset. This offset can be added to |
| 388 | * an opcode to get the right opcode type. Most opcodes |
| 389 | * are ordered: int, long, float, double, array. For |
| 390 | * example: iload, lload fload, dload, aload. So the |
| 391 | * appropriate opcode is iadd + type.getTypeCodeOffset(). |
| 392 | */ |
| 393 | public int getTypeCodeOffset() { |
| 394 | switch (typeCode) { |
| 395 | case TC_BOOLEAN: |
| 396 | case TC_BYTE: |
| 397 | case TC_SHORT: |
| 398 | case TC_CHAR: |
| 399 | case TC_INT: |
| 400 | return 0; |
| 401 | case TC_LONG: |
| 402 | return 1; |
| 403 | case TC_FLOAT: |
| 404 | return 2; |
| 405 | case TC_DOUBLE: |
| 406 | return 3; |
| 407 | case TC_NULL: |
| 408 | case TC_ARRAY: |
| 409 | case TC_CLASS: |
| 410 | return 4; |
| 411 | } |
| 412 | throw new CompilerError("invalid typecode: " + typeCode); |
| 413 | } |
| 414 | |
| 415 | /** |
| 416 | * Convert a Type to a string, if abbrev is true class names are |
| 417 | * not fully qualified, if ret is true the return type is included. |
| 418 | */ |
| 419 | public String typeString(String id, boolean abbrev, boolean ret) { |
| 420 | String s = null; |
| 421 | |
| 422 | switch (typeCode) { |
| 423 | case TC_NULL: s = "null"; break; |
| 424 | case TC_VOID: s = "void"; break; |
| 425 | case TC_BOOLEAN: s = "boolean"; break; |
| 426 | case TC_BYTE: s = "byte"; break; |
| 427 | case TC_CHAR: s = "char"; break; |
| 428 | case TC_SHORT: s = "short"; break; |
| 429 | case TC_INT: s = "int"; break; |
| 430 | case TC_LONG: s = "long"; break; |
| 431 | case TC_FLOAT: s = "float"; break; |
| 432 | case TC_DOUBLE: s = "double"; break; |
| 433 | case TC_ERROR: s = "<error>"; |
| 434 | if (this==tPackage) s = "<package>"; |
| 435 | break; |
| 436 | default: s = "unknown"; |
| 437 | } |
| 438 | |
| 439 | return (id.length() > 0) ? s + " " + id : s; |
| 440 | } |
| 441 | |
| 442 | /** |
| 443 | * Create a type string, given an identifier. |
| 444 | */ |
| 445 | public String typeString(String id) { |
| 446 | return typeString(id, false, true); |
| 447 | } |
| 448 | |
| 449 | /** |
| 450 | * Convert to a String |
| 451 | */ |
| 452 | public String toString() { |
| 453 | return typeString("", false, true); |
| 454 | } |
| 455 | } |