net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/lookup/MethodScope.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.compiler.lookup;
  12
  13 import net.sourceforge.phpdt.internal.compiler.flow.FlowInfo;
  14 import net.sourceforge.phpdt.internal.compiler.flow.UnconditionalFlowInfo;
  15 import net.sourceforge.phpdt.internal.compiler.impl.ReferenceContext;
  16 import net.sourceforge.phpdt.internal.compiler.problem.ProblemReporter;
  17 import net.sourceforge.phpeclipse.internal.compiler.ast.AbstractMethodDeclaration;
  18 import net.sourceforge.phpeclipse.internal.compiler.ast.ConstructorDeclaration;
  19 import net.sourceforge.phpeclipse.internal.compiler.ast.QualifiedNameReference;
  20 import net.sourceforge.phpeclipse.internal.compiler.ast.SingleNameReference;
  21 import net.sourceforge.phpeclipse.internal.compiler.ast.TypeDeclaration;
  22
  23 /**
  24  * Particular block scope used for methods, constructors or clinits, representing
  25  * its outermost blockscope. Note also that such a scope will be provided to enclose
  26  * field initializers subscopes as well.
  27  */
  28 public class MethodScope extends BlockScope {
  29
  30         public ReferenceContext referenceContext;
  31         public boolean isStatic; // method modifier or initializer one
  32
  33         //fields used during name resolution
  34         public static final int NotInFieldDecl = -1; //must be a negative value
  35         public boolean isConstructorCall = false;
  36         public FieldBinding initializedField; // the field being initialized
  37         public int fieldDeclarationIndex = NotInFieldDecl;
  38
  39         // flow analysis
  40         public int analysisIndex; // for setting flow-analysis id
  41         public boolean isPropagatingInnerClassEmulation;
  42
  43         // for local variables table attributes
  44         public int lastIndex = 0;
  45         public long[] definiteInits = new long[4];
  46         public long[][] extraDefiniteInits = new long[4][];
  47
  48         // inner-emulation
  49         public SyntheticArgumentBinding[] extraSyntheticArguments;
  50
  51         public MethodScope(ClassScope parent, ReferenceContext context, boolean isStatic) {
  52
  53                 super(METHOD_SCOPE, parent);
  54                 locals = new LocalVariableBinding[5];
  55                 this.referenceContext = context;
  56                 this.isStatic = isStatic;
  57                 this.startIndex = 0;
  58         }
  59
  60         /* Spec : 8.4.3 & 9.4
  61          */
  62         private void checkAndSetModifiersForConstructor(MethodBinding methodBinding) {
  63
  64                 int modifiers = methodBinding.modifiers;
  65                 if ((modifiers & AccAlternateModifierProblem) != 0)
  66                         problemReporter().duplicateModifierForMethod(
  67                                 methodBinding.declaringClass,
  68                                 (AbstractMethodDeclaration) referenceContext);
  69
  70                 if (((ConstructorDeclaration) referenceContext).isDefaultConstructor) {
  71                         if (methodBinding.declaringClass.isPublic())
  72                                 modifiers |= AccPublic;
  73                         else if (methodBinding.declaringClass.isProtected())
  74                                 modifiers |= AccProtected;
  75                 }
  76
  77                 // after this point, tests on the 16 bits reserved.
  78                 int realModifiers = modifiers & AccJustFlag;
  79
  80                 // check for abnormal modifiers
  81                 int unexpectedModifiers =
  82                         ~(AccPublic | AccPrivate | AccProtected);// | AccStrictfp);
  83                 if ((realModifiers & unexpectedModifiers) != 0)
  84                         problemReporter().illegalModifierForMethod(
  85                                 methodBinding.declaringClass,
  86                                 (AbstractMethodDeclaration) referenceContext);
  87 //              else if (
  88 //                      (((AbstractMethodDeclaration) referenceContext).modifiers & AccStrictfp) != 0)
  89 //                      // must check the parse node explicitly
  90 //                      problemReporter().illegalModifierForMethod(
  91 //                              methodBinding.declaringClass,
  92 //                              (AbstractMethodDeclaration) referenceContext);
  93
  94                 // check for incompatible modifiers in the visibility bits, isolate the visibility bits
  95                 int accessorBits = realModifiers & (AccPublic | AccProtected | AccPrivate);
  96                 if ((accessorBits & (accessorBits - 1)) != 0) {
  97                         problemReporter().illegalVisibilityModifierCombinationForMethod(
  98                                 methodBinding.declaringClass,
  99                                 (AbstractMethodDeclaration) referenceContext);
 100
 101                         // need to keep the less restrictive
 102                         if ((accessorBits & AccPublic) != 0) {
 103                                 if ((accessorBits & AccProtected) != 0)
 104                                         modifiers ^= AccProtected;
 105                                 if ((accessorBits & AccPrivate) != 0)
 106                                         modifiers ^= AccPrivate;
 107                         }
 108                         if ((accessorBits & AccProtected) != 0)
 109                                 if ((accessorBits & AccPrivate) != 0)
 110                                         modifiers ^= AccPrivate;
 111                 }
 112
 113                 // if the receiver's declaring class is a private nested type, then make sure the receiver is not private (causes problems for inner type emulation)
 114                 if (methodBinding.declaringClass.isPrivate())
 115                         if ((modifiers & AccPrivate) != 0)
 116                                 modifiers ^= AccPrivate;
 117
 118                 methodBinding.modifiers = modifiers;
 119         }
 120
 121         /* Spec : 8.4.3 & 9.4
 122          */
 123         private void checkAndSetModifiersForMethod(MethodBinding methodBinding) {
 124
 125                 int modifiers = methodBinding.modifiers;
 126                 if ((modifiers & AccAlternateModifierProblem) != 0)
 127                         problemReporter().duplicateModifierForMethod(
 128                                 methodBinding.declaringClass,
 129                                 (AbstractMethodDeclaration) referenceContext);
 130
 131                 // after this point, tests on the 16 bits reserved.
 132                 int realModifiers = modifiers & AccJustFlag;
 133
 134                 // set the requested modifiers for a method in an interface
 135                 if (methodBinding.declaringClass.isInterface()) {
 136                         if ((realModifiers & ~(AccPublic | AccAbstract)) != 0)
 137                                 problemReporter().illegalModifierForInterfaceMethod(
 138                                         methodBinding.declaringClass,
 139                                         (AbstractMethodDeclaration) referenceContext);
 140                         return;
 141                 }
 142
 143                 // check for abnormal modifiers
 144                 int unexpectedModifiers =
 145                         ~(
 146                                 AccPublic
 147                                         | AccPrivate
 148                                         | AccProtected
 149                                         | AccAbstract
 150                                         | AccStatic
 151                                         | AccFinal);
 152 //                                      | AccSynchronized
 153 //                                      | AccNative
 154 //                                      | AccStrictfp);
 155                 if ((realModifiers & unexpectedModifiers) != 0)
 156                         problemReporter().illegalModifierForMethod(
 157                                 methodBinding.declaringClass,
 158                                 (AbstractMethodDeclaration) referenceContext);
 159
 160                 // check for incompatible modifiers in the visibility bits, isolate the visibility bits
 161                 int accessorBits = realModifiers & (AccPublic | AccProtected | AccPrivate);
 162                 if ((accessorBits & (accessorBits - 1)) != 0) {
 163                         problemReporter().illegalVisibilityModifierCombinationForMethod(
 164                                 methodBinding.declaringClass,
 165                                 (AbstractMethodDeclaration) referenceContext);
 166
 167                         // need to keep the less restrictive
 168                         if ((accessorBits & AccPublic) != 0) {
 169                                 if ((accessorBits & AccProtected) != 0)
 170                                         modifiers ^= AccProtected;
 171                                 if ((accessorBits & AccPrivate) != 0)
 172                                         modifiers ^= AccPrivate;
 173                         }
 174                         if ((accessorBits & AccProtected) != 0)
 175                                 if ((accessorBits & AccPrivate) != 0)
 176                                         modifiers ^= AccPrivate;
 177                 }
 178
 179                 // check for modifiers incompatible with abstract modifier
 180                 if ((modifiers & AccAbstract) != 0) {
 181                         int incompatibleWithAbstract =
 182                                 AccPrivate | AccStatic | AccFinal;// | AccSynchronized | AccNative | AccStrictfp;
 183                         if ((modifiers & incompatibleWithAbstract) != 0)
 184                                 problemReporter().illegalAbstractModifierCombinationForMethod(
 185                                         methodBinding.declaringClass,
 186                                         (AbstractMethodDeclaration) referenceContext);
 187                         if (!methodBinding.declaringClass.isAbstract())
 188                                 problemReporter().abstractMethodInAbstractClass(
 189                                         (SourceTypeBinding) methodBinding.declaringClass,
 190                                         (AbstractMethodDeclaration) referenceContext);
 191                 }
 192
 193                 /* DISABLED for backward compatibility with javac (if enabled should also mark private methods as final)
 194                 // methods from a final class are final : 8.4.3.3
 195                 if (methodBinding.declaringClass.isFinal())
 196                         modifiers |= AccFinal;
 197                 */
 198                 // native methods cannot also be tagged as strictfp
 199 //              if ((modifiers & AccNative) != 0 && (modifiers & AccStrictfp) != 0)
 200 //                      problemReporter().nativeMethodsCannotBeStrictfp(
 201 //                              methodBinding.declaringClass,
 202 //                              (AbstractMethodDeclaration) referenceContext);
 203
 204                 // static members are only authorized in a static member or top level type
 205                 if (((realModifiers & AccStatic) != 0)
 206                         && methodBinding.declaringClass.isNestedType()
 207                         && !methodBinding.declaringClass.isStatic())
 208                         problemReporter().unexpectedStaticModifierForMethod(
 209                                 methodBinding.declaringClass,
 210                                 (AbstractMethodDeclaration) referenceContext);
 211
 212                 methodBinding.modifiers = modifiers;
 213         }
 214
 215         /* Compute variable positions in scopes given an initial position offset
 216          * ignoring unused local variables.
 217          *
 218          * Deal with arguments here, locals and subscopes are processed in BlockScope method
 219          */
 220 //      public void computeLocalVariablePositions(int initOffset, CodeStream codeStream) {
 221 //
 222 //              boolean isReportingUnusedArgument = false;
 223 //
 224 //              if (referenceContext instanceof AbstractMethodDeclaration) {
 225 //                      AbstractMethodDeclaration methodDecl = (AbstractMethodDeclaration)referenceContext;
 226 //                      MethodBinding method = methodDecl.binding;
 227 //                      CompilerOptions options = compilationUnitScope().environment.options;
 228 //                      if (!(method.isAbstract()
 229 //                                      || (method.isImplementing() && !options.reportUnusedParameterWhenImplementingAbstract)
 230 //                                      || (method.isOverriding() && !method.isImplementing() && !options.reportUnusedParameterWhenOverridingConcrete)
 231 //                                      || method.isMain())) {
 232 //                              isReportingUnusedArgument = true;
 233 //                      }
 234 //              }
 235 //              this.offset = initOffset;
 236 //              this.maxOffset = initOffset;
 237 //
 238 //              // manage arguments
 239 //              int ilocal = 0, maxLocals = this.localIndex;
 240 //              while (ilocal < maxLocals) {
 241 //                      LocalVariableBinding local = locals[ilocal];
 242 //                      if (local == null || !local.isArgument) break; // done with arguments
 243 //
 244 //                      // do not report fake used variable
 245 //                      if (isReportingUnusedArgument
 246 //                                      && local.useFlag == LocalVariableBinding.UNUSED
 247 //                                      && ((local.declaration.bits & ASTNode.IsLocalDeclarationReachableMASK) != 0)) { // declaration is reachable
 248 //                              this.problemReporter().unusedArgument(local.declaration);
 249 //                      }
 250 //
 251 //                      // record user-defined argument for attribute generation
 252 //                      codeStream.record(local);
 253 //
 254 //                      // assign variable position
 255 //                      local.resolvedPosition = this.offset;
 256 //
 257 //                      if ((local.type == LongBinding) || (local.type == DoubleBinding)) {
 258 //                              this.offset += 2;
 259 //                      } else {
 260 //                              this.offset++;
 261 //                      }
 262 //                      // check for too many arguments/local variables
 263 //                      if (this.offset > 0xFF) { // no more than 255 words of arguments
 264 //                              this.problemReporter().noMoreAvailableSpaceForArgument(local, local.declaration);
 265 //                      }
 266 //                      ilocal++;
 267 //              }
 268 //
 269 //              // sneak in extra argument before other local variables
 270 //              if (extraSyntheticArguments != null) {
 271 //                      for (int iarg = 0, maxArguments = extraSyntheticArguments.length; iarg < maxArguments; iarg++){
 272 //                              SyntheticArgumentBinding argument = extraSyntheticArguments[iarg];
 273 //                              argument.resolvedPosition = this.offset;
 274 //                              if ((argument.type == LongBinding) || (argument.type == DoubleBinding)){
 275 //                                      this.offset += 2;
 276 //                              } else {
 277 //                                      this.offset++;
 278 //                              }
 279 //                              if (this.offset > 0xFF) { // no more than 255 words of arguments
 280 //                                      this.problemReporter().noMoreAvailableSpaceForArgument(argument, (ASTNode)this.referenceContext);
 281 //                              }
 282 //                      }
 283 //              }
 284 //              this.computeLocalVariablePositions(ilocal, this.offset, codeStream);
 285 //      }
 286
 287         /* Error management:
 288          *              keep null for all the errors that prevent the method to be created
 289          *              otherwise return a correct method binding (but without the element
 290          *              that caused the problem) : ie : Incorrect thrown exception
 291          */
 292         MethodBinding createMethod(AbstractMethodDeclaration method) {
 293
 294                 // is necessary to ensure error reporting
 295                 this.referenceContext = method;
 296                 method.scope = this;
 297                 SourceTypeBinding declaringClass = referenceType().binding;
 298                 int modifiers = method.modifiers | AccUnresolved;
 299                 if (method.isConstructor()) {
 300                         method.binding = new MethodBinding(modifiers, null, null, declaringClass);
 301                         checkAndSetModifiersForConstructor(method.binding);
 302                 } else {
 303                         if (declaringClass.isInterface())
 304                                 modifiers |= AccPublic | AccAbstract;
 305                         method.binding =
 306                                 new MethodBinding(modifiers, method.selector, null, null, null, declaringClass);
 307                         checkAndSetModifiersForMethod(method.binding);
 308                 }
 309
 310                 this.isStatic = method.binding.isStatic();
 311                 return method.binding;
 312         }
 313
 314         /* Overridden to detect the error case inside an explicit constructor call:
 315
 316         class X {
 317                 int i;
 318                 X myX;
 319                 X(X x) {
 320                         this(i, myX.i, x.i); // same for super calls... only the first 2 field accesses are errors
 321                 }
 322         }
 323         */
 324         public FieldBinding findField(
 325                 TypeBinding receiverType,
 326                 char[] fieldName,
 327                 InvocationSite invocationSite) {
 328
 329                 FieldBinding field = super.findField(receiverType, fieldName, invocationSite);
 330                 if (field == null)
 331                         return null;
 332                 if (!field.isValidBinding())
 333                         return field; // answer the error field
 334                 if (field.isStatic())
 335                         return field; // static fields are always accessible
 336
 337                 if (!isConstructorCall || receiverType != enclosingSourceType())
 338                         return field;
 339
 340                 if (invocationSite instanceof SingleNameReference)
 341                         return new ProblemFieldBinding(
 342                                 field.declaringClass,
 343                                 fieldName,
 344                                 NonStaticReferenceInConstructorInvocation);
 345                 if (invocationSite instanceof QualifiedNameReference) {
 346                         // look to see if the field is the first binding
 347                         QualifiedNameReference name = (QualifiedNameReference) invocationSite;
 348                         if (name.binding == null)
 349                                 // only true when the field is the fieldbinding at the beginning of name's tokens
 350                                 return new ProblemFieldBinding(
 351                                         field.declaringClass,
 352                                         fieldName,
 353                                         NonStaticReferenceInConstructorInvocation);
 354                 }
 355                 return field;
 356         }
 357
 358         public boolean isInsideInitializer() {
 359
 360                 return (referenceContext instanceof TypeDeclaration);
 361         }
 362
 363         public boolean isInsideInitializerOrConstructor() {
 364
 365                 return (referenceContext instanceof TypeDeclaration)
 366                         || (referenceContext instanceof ConstructorDeclaration);
 367         }
 368
 369         /* Answer the problem reporter to use for raising new problems.
 370          *
 371          * Note that as a side-effect, this updates the current reference context
 372          * (unit, type or method) in case the problem handler decides it is necessary
 373          * to abort.
 374          */
 375         public ProblemReporter problemReporter() {
 376
 377                 MethodScope outerMethodScope;
 378                 if ((outerMethodScope = outerMostMethodScope()) == this) {
 379                         ProblemReporter problemReporter = referenceCompilationUnit().problemReporter;
 380                         problemReporter.referenceContext = referenceContext;
 381                         return problemReporter;
 382                 } else {
 383                         return outerMethodScope.problemReporter();
 384                 }
 385         }
 386
 387         public final int recordInitializationStates(FlowInfo flowInfo) {
 388
 389                 if (!flowInfo.isReachable()) return -1;
 390
 391                 UnconditionalFlowInfo unconditionalFlowInfo = flowInfo.unconditionalInits();
 392                 long[] extraInits = unconditionalFlowInfo.extraDefiniteInits;
 393                 long inits = unconditionalFlowInfo.definiteInits;
 394                 checkNextEntry : for (int i = lastIndex; --i >= 0;) {
 395                         if (definiteInits[i] == inits) {
 396                                 long[] otherInits = extraDefiniteInits[i];
 397                                 if ((extraInits != null) && (otherInits != null)) {
 398                                         if (extraInits.length == otherInits.length) {
 399                                                 int j, max;
 400                                                 for (j = 0, max = extraInits.length; j < max; j++) {
 401                                                         if (extraInits[j] != otherInits[j]) {
 402                                                                 continue checkNextEntry;
 403                                                         }
 404                                                 }
 405                                                 return i;
 406                                         }
 407                                 } else {
 408                                         if ((extraInits == null) && (otherInits == null)) {
 409                                                 return i;
 410                                         }
 411                                 }
 412                         }
 413                 }
 414
 415                 // add a new entry
 416                 if (definiteInits.length == lastIndex) {
 417                         // need a resize
 418                         System.arraycopy(
 419                                 definiteInits,
 420                                 0,
 421                                 (definiteInits = new long[lastIndex + 20]),
 422                                 0,
 423                                 lastIndex);
 424                         System.arraycopy(
 425                                 extraDefiniteInits,
 426                                 0,
 427                                 (extraDefiniteInits = new long[lastIndex + 20][]),
 428                                 0,
 429                                 lastIndex);
 430                 }
 431                 definiteInits[lastIndex] = inits;
 432                 if (extraInits != null) {
 433                         extraDefiniteInits[lastIndex] = new long[extraInits.length];
 434                         System.arraycopy(
 435                                 extraInits,
 436                                 0,
 437                                 extraDefiniteInits[lastIndex],
 438                                 0,
 439                                 extraInits.length);
 440                 }
 441                 return lastIndex++;
 442         }
 443
 444         /* Answer the reference type of this scope.
 445         *
 446         * It is the nearest enclosing type of this scope.
 447         */
 448         public TypeDeclaration referenceType() {
 449
 450                 return (TypeDeclaration) ((ClassScope) parent).referenceContext;
 451         }
 452
 453         String basicToString(int tab) {
 454
 455                 String newLine = "\n"; //$NON-NLS-1$
 456                 for (int i = tab; --i >= 0;)
 457                         newLine += "\t"; //$NON-NLS-1$
 458
 459                 String s = newLine + "--- Method Scope ---"; //$NON-NLS-1$
 460                 newLine += "\t"; //$NON-NLS-1$
 461                 s += newLine + "locals:"; //$NON-NLS-1$
 462                 for (int i = 0; i < localIndex; i++)
 463                         s += newLine + "\t" + locals[i].toString(); //$NON-NLS-1$
 464                 s += newLine + "startIndex = " + startIndex; //$NON-NLS-1$
 465                 s += newLine + "isConstructorCall = " + isConstructorCall; //$NON-NLS-1$
 466                 s += newLine + "initializedField = " + initializedField; //$NON-NLS-1$
 467                 s += newLine + "fieldDeclarationIndex = " + fieldDeclarationIndex; //$NON-NLS-1$
 468                 s += newLine + "referenceContext = " + referenceContext; //$NON-NLS-1$
 469                 return s;
 470         }
 471
 472 }