Пример #1
0
  /**
   * Casting an enclosing instance will considered as useful if removing it would actually bind to a
   * different type
   */
  public static void checkNeedForEnclosingInstanceCast(
      BlockScope scope,
      Expression enclosingInstance,
      TypeBinding enclosingInstanceType,
      TypeBinding memberType) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    TypeBinding castedExpressionType = ((CastExpression) enclosingInstance).expression.resolvedType;
    if (castedExpressionType == null) return; // cannot do better
    // obvious identity cast
    if (castedExpressionType == enclosingInstanceType) {
      scope.problemReporter().unnecessaryCast((CastExpression) enclosingInstance);
    } else if (castedExpressionType == TypeBinding.NULL) {
      return; // tolerate null enclosing instance cast
    } else {
      TypeBinding alternateEnclosingInstanceType = castedExpressionType;
      if (castedExpressionType.isBaseType() || castedExpressionType.isArrayType())
        return; // error case
      if (memberType
          == scope.getMemberType(
              memberType.sourceName(), (ReferenceBinding) alternateEnclosingInstanceType)) {
        scope.problemReporter().unnecessaryCast((CastExpression) enclosingInstance);
      }
    }
  }
Пример #2
0
  /**
   * Cast expressions will considered as useful if removing them all would actually bind to a
   * different method (no fine grain analysis on per casted argument basis, simply separate widening
   * cast from narrowing ones)
   */
  public static void checkNeedForArgumentCasts(
      BlockScope scope,
      Expression receiver,
      TypeBinding receiverType,
      MethodBinding binding,
      Expression[] arguments,
      TypeBinding[] argumentTypes,
      final InvocationSite invocationSite) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    int length = argumentTypes.length;

    // iterate over arguments, and retrieve original argument types (before cast)
    TypeBinding[] rawArgumentTypes = argumentTypes;
    for (int i = 0; i < length; i++) {
      Expression argument = arguments[i];
      if (argument instanceof CastExpression) {
        // narrowing conversion on base type may change value, thus necessary
        if ((argument.bits & ASTNode.UnnecessaryCast) == 0 && argument.resolvedType.isBaseType()) {
          continue;
        }
        TypeBinding castedExpressionType = ((CastExpression) argument).expression.resolvedType;
        if (castedExpressionType == null) return; // cannot do better
        // obvious identity cast
        if (castedExpressionType == argumentTypes[i]) {
          scope.problemReporter().unnecessaryCast((CastExpression) argument);
        } else if (castedExpressionType == TypeBinding.NULL) {
          continue; // tolerate null argument cast
        } else if ((argument.implicitConversion & TypeIds.BOXING) != 0) {
          continue; // boxing has a side effect: (int) char   is not boxed as simple char
        } else {
          if (rawArgumentTypes == argumentTypes) {
            System.arraycopy(
                rawArgumentTypes, 0, rawArgumentTypes = new TypeBinding[length], 0, length);
          }
          // retain original argument type
          rawArgumentTypes[i] = castedExpressionType;
        }
      }
    }
    // perform alternate lookup with original types
    if (rawArgumentTypes != argumentTypes) {
      checkAlternateBinding(
          scope,
          receiver,
          receiverType,
          binding,
          arguments,
          argumentTypes,
          rawArgumentTypes,
          invocationSite);
    }
  }
Пример #3
0
  /**
   * Complain if assigned expression is cast, but not actually used as such, e.g. Object o = (List)
   * object;
   */
  public static void checkNeedForAssignedCast(
      BlockScope scope, TypeBinding expectedType, CastExpression rhs) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    TypeBinding castedExpressionType = rhs.expression.resolvedType;
    //	int i = (byte) n; // cast still had side effect
    // double d = (float) n; // cast to float is unnecessary
    if (castedExpressionType == null || rhs.resolvedType.isBaseType()) return;
    // if (castedExpressionType.id == T_null) return; // tolerate null expression cast
    if (castedExpressionType.isCompatibleWith(expectedType)) {
      scope.problemReporter().unnecessaryCast(rhs);
    }
  }
Пример #4
0
  /**
   * Complain if cast expression is cast, but not actually needed, int i = (int)(Integer) 12; Note
   * that this (int) cast is however needed: Integer i = 0; char c = (char)((int) i);
   */
  public static void checkNeedForCastCast(BlockScope scope, CastExpression enclosingCast) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    CastExpression nestedCast = (CastExpression) enclosingCast.expression;
    if ((nestedCast.bits & ASTNode.UnnecessaryCast) == 0) return;
    // check if could cast directly to enclosing cast type, without intermediate type cast
    CastExpression alternateCast = new CastExpression(null, enclosingCast.type);
    alternateCast.resolvedType = enclosingCast.resolvedType;
    if (!alternateCast.checkCastTypesCompatibility(
        scope,
        enclosingCast.resolvedType,
        nestedCast.expression.resolvedType,
        null /* no expr to avoid side-effects*/)) return;
    scope.problemReporter().unnecessaryCast(nestedCast);
  }
Пример #5
0
 void checkAssignment(BlockScope scope, TypeBinding lhsType, TypeBinding rhsType) {
   FieldBinding leftField = getLastField(this.lhs);
   if (leftField != null
       && rhsType != TypeBinding.NULL
       && (lhsType.kind() == Binding.WILDCARD_TYPE)
       && ((WildcardBinding) lhsType).boundKind != Wildcard.SUPER) {
     scope.problemReporter().wildcardAssignment(lhsType, rhsType, this.expression);
   } else if (leftField != null
       && !leftField.isStatic()
       && leftField.declaringClass != null /*length pseudo field*/
       && leftField.declaringClass.isRawType()) {
     scope.problemReporter().unsafeRawFieldAssignment(leftField, rhsType, this.lhs);
   } else if (rhsType.needsUncheckedConversion(lhsType)) {
     scope.problemReporter().unsafeTypeConversion(this.expression, rhsType, lhsType);
   }
 }
Пример #6
0
  public TypeBinding resolveType(BlockScope scope) {
    // due to syntax lhs may be only a NameReference, a FieldReference or an ArrayReference
    this.constant = Constant.NotAConstant;
    if (!(this.lhs instanceof Reference) || this.lhs.isThis()) {
      scope.problemReporter().expressionShouldBeAVariable(this.lhs);
      return null;
    }
    TypeBinding lhsType = lhs.resolveType(scope);
    this.expression.setExpectedType(lhsType); // needed in case of generic method invocation
    if (lhsType != null) {
      this.resolvedType = lhsType.capture(scope, this.sourceEnd);
    }
    TypeBinding rhsType = this.expression.resolveType(scope);
    if (lhsType == null || rhsType == null) {
      return null;
    }
    // check for assignment with no effect
    Binding left = getDirectBinding(this.lhs);
    if (left != null && left == getDirectBinding(this.expression)) {
      scope.problemReporter().assignmentHasNoEffect(this, left.shortReadableName());
    }

    // Compile-time conversion of base-types : implicit narrowing integer into byte/short/character
    // may require to widen the rhs expression at runtime
    if (lhsType != rhsType) { // must call before computeConversion() and typeMismatchError()
      scope.compilationUnitScope().recordTypeConversion(lhsType, rhsType);
    }
    if ((this.expression.isConstantValueOfTypeAssignableToType(rhsType, lhsType)
            || (lhsType.isBaseType() && BaseTypeBinding.isWidening(lhsType.id, rhsType.id)))
        || rhsType.isCompatibleWith(lhsType)) {
      this.expression.computeConversion(scope, lhsType, rhsType);
      checkAssignment(scope, lhsType, rhsType);
      if (this.expression instanceof CastExpression
          && (this.expression.bits & ASTNode.UnnecessaryCast) == 0) {
        CastExpression.checkNeedForAssignedCast(scope, lhsType, (CastExpression) this.expression);
      }
      return this.resolvedType;
    } else if (scope.isBoxingCompatibleWith(rhsType, lhsType)
        || (rhsType.isBaseType() // narrowing then boxing ?
            && scope.compilerOptions().sourceLevel >= ClassFileConstants.JDK1_5 // autoboxing
            && !lhsType.isBaseType()
            && this.expression.isConstantValueOfTypeAssignableToType(
                rhsType, scope.environment().computeBoxingType(lhsType)))) {
      this.expression.computeConversion(scope, lhsType, rhsType);
      if (this.expression instanceof CastExpression
          && (this.expression.bits & ASTNode.UnnecessaryCast) == 0) {
        CastExpression.checkNeedForAssignedCast(scope, lhsType, (CastExpression) this.expression);
      }
      return this.resolvedType;
    }
    scope.problemReporter().typeMismatchError(rhsType, lhsType, this.expression, this.lhs);
    return lhsType;
  }
Пример #7
0
  /**
   * Only complain for identity cast, since other type of casts may be useful: e.g. ~((~(long) 0) <<
   * 32) is different from: ~((~0) << 32)
   */
  public static void checkNeedForArgumentCast(
      BlockScope scope,
      int operator,
      int operatorSignature,
      Expression expression,
      int expressionTypeId) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    // check need for left operand cast
    int alternateLeftTypeId = expressionTypeId;
    if ((expression.bits & ASTNode.UnnecessaryCast) == 0 && expression.resolvedType.isBaseType()) {
      // narrowing conversion on base type may change value, thus necessary
      return;
    } else {
      TypeBinding alternateLeftType = ((CastExpression) expression).expression.resolvedType;
      if (alternateLeftType == null) return; // cannot do better
      if ((alternateLeftTypeId = alternateLeftType.id)
          == expressionTypeId) { // obvious identity cast
        scope.problemReporter().unnecessaryCast((CastExpression) expression);
        return;
      } else if (alternateLeftTypeId == TypeIds.T_null) {
        alternateLeftTypeId = expressionTypeId; // tolerate null argument cast
        return;
      }
    }
    /*		tolerate widening cast in unary expressions, as may be used when combined in binary expressions (41680)
    		int alternateOperatorSignature = OperatorExpression.OperatorSignatures[operator][(alternateLeftTypeId << 4) + alternateLeftTypeId];
    		// (cast)  left   Op (cast)  right --> result
    		//  1111   0000       1111   0000     1111
    		//  <<16   <<12       <<8    <<4       <<0
    		final int CompareMASK = (0xF<<16) + (0xF<<8) + 0xF; // mask hiding compile-time types
    		if ((operatorSignature & CompareMASK) == (alternateOperatorSignature & CompareMASK)) { // same promotions and result
    			scope.problemReporter().unnecessaryCastForArgument((CastExpression)expression,  TypeBinding.wellKnownType(scope, expression.implicitConversion >> 4));
    		}
    */
  }
Пример #8
0
  /**
   * @see
   *     xap.lui.compile.ca.jdt.internal.compiler.ast.Expression#resolveTypeExpecting(xap.lui.compile.ca.jdt.internal.compiler.lookup.BlockScope,
   *     xap.lui.compile.ca.jdt.internal.compiler.lookup.TypeBinding)
   */
  public TypeBinding resolveTypeExpecting(BlockScope scope, TypeBinding expectedType) {

    TypeBinding type = super.resolveTypeExpecting(scope, expectedType);
    if (type == null) return null;
    TypeBinding lhsType = this.resolvedType;
    TypeBinding rhsType = this.expression.resolvedType;
    // signal possible accidental boolean assignment (instead of using '==' operator)
    if (expectedType == TypeBinding.BOOLEAN
        && lhsType == TypeBinding.BOOLEAN
        && (this.lhs.bits & IsStrictlyAssigned) != 0) {
      scope.problemReporter().possibleAccidentalBooleanAssignment(this);
    }
    checkAssignment(scope, lhsType, rhsType);
    return type;
  }
Пример #9
0
  public TypeBinding resolveType(BlockScope scope) {
    // compute a new constant if the cast is effective

    // due to the fact an expression may start with ( and that a cast can also start with (
    // the field is an expression....it can be a TypeReference OR a NameReference Or
    // any kind of Expression <-- this last one is invalid.......

    this.constant = Constant.NotAConstant;
    this.implicitConversion = TypeIds.T_undefined;

    if ((this.type instanceof TypeReference)
        || (this.type instanceof NameReference)
            && ((this.type.bits & ASTNode.ParenthesizedMASK) >> ASTNode.ParenthesizedSHIFT)
                == 0) { // no extra parenthesis around type: ((A))exp

      boolean exprContainCast = false;

      TypeBinding castType = this.resolvedType = this.type.resolveType(scope);
      // expression.setExpectedType(this.resolvedType); // needed in case of generic method
      // invocation
      if (this.expression instanceof CastExpression) {
        this.expression.bits |= ASTNode.DisableUnnecessaryCastCheck;
        exprContainCast = true;
      }
      TypeBinding expressionType = this.expression.resolveType(scope);
      if (castType != null) {
        if (expressionType != null) {
          boolean isLegal =
              checkCastTypesCompatibility(scope, castType, expressionType, this.expression);
          if (isLegal) {
            this.expression.computeConversion(scope, castType, expressionType);
            if ((this.bits & ASTNode.UnsafeCast) != 0) { // unsafe cast
              scope.problemReporter().unsafeCast(this, scope);
            } else {
              if (castType.isRawType()
                  && scope.compilerOptions().getSeverity(CompilerOptions.RawTypeReference)
                      != ProblemSeverities.Ignore) {
                scope.problemReporter().rawTypeReference(this.type, castType);
              }
              if ((this.bits & (ASTNode.UnnecessaryCast | ASTNode.DisableUnnecessaryCastCheck))
                  == ASTNode.UnnecessaryCast) { // unnecessary cast
                if (!isIndirectlyUsed()) // used for generic type inference or boxing ?
                scope.problemReporter().unnecessaryCast(this);
              }
            }
          } else { // illegal cast
            if ((castType.tagBits & TagBits.HasMissingType)
                == 0) { // no complaint if secondary error
              scope.problemReporter().typeCastError(this, castType, expressionType);
            }
            this.bits |= ASTNode.DisableUnnecessaryCastCheck; // disable further secondary diagnosis
          }
        }
        this.resolvedType = castType.capture(scope, this.sourceEnd);
        if (exprContainCast) {
          checkNeedForCastCast(scope, this);
        }
      }
      return this.resolvedType;
    } else { // expression as a cast
      TypeBinding expressionType = this.expression.resolveType(scope);
      if (expressionType == null) return null;
      scope.problemReporter().invalidTypeReference(this.type);
      return null;
    }
  }
Пример #10
0
  private static void checkAlternateBinding(
      BlockScope scope,
      Expression receiver,
      TypeBinding receiverType,
      MethodBinding binding,
      Expression[] arguments,
      TypeBinding[] originalArgumentTypes,
      TypeBinding[] alternateArgumentTypes,
      final InvocationSite invocationSite) {
    InvocationSite fakeInvocationSite =
        new InvocationSite() {
          public TypeBinding[] genericTypeArguments() {
            return null;
          }

          public boolean isSuperAccess() {
            return invocationSite.isSuperAccess();
          }

          public boolean isTypeAccess() {
            return invocationSite.isTypeAccess();
          }

          public void setActualReceiverType(ReferenceBinding actualReceiverType) {
            /* ignore */
          }

          public void setDepth(int depth) {
            /* ignore */
          }

          public void setFieldIndex(int depth) {
            /* ignore */
          }

          public int sourceStart() {
            return 0;
          }

          public int sourceEnd() {
            return 0;
          }
        };
    MethodBinding bindingIfNoCast;
    if (binding.isConstructor()) {
      bindingIfNoCast =
          scope.getConstructor(
              (ReferenceBinding) receiverType, alternateArgumentTypes, fakeInvocationSite);
    } else {
      bindingIfNoCast =
          receiver.isImplicitThis()
              ? scope.getImplicitMethod(
                  binding.selector, alternateArgumentTypes, fakeInvocationSite)
              : scope.getMethod(
                  receiverType, binding.selector, alternateArgumentTypes, fakeInvocationSite);
    }
    if (bindingIfNoCast == binding) {
      int argumentLength = originalArgumentTypes.length;
      if (binding.isVarargs()) {
        int paramLength = binding.parameters.length;
        if (paramLength == argumentLength) {
          int varargsIndex = paramLength - 1;
          ArrayBinding varargsType = (ArrayBinding) binding.parameters[varargsIndex];
          TypeBinding lastArgType = alternateArgumentTypes[varargsIndex];
          // originalType may be compatible already, but cast mandated
          // to clarify between varargs/non-varargs call
          if (varargsType.dimensions != lastArgType.dimensions()) {
            return;
          }
          if (lastArgType.isCompatibleWith(varargsType.elementsType())
              && lastArgType.isCompatibleWith(varargsType)) {
            return;
          }
        }
      }
      for (int i = 0; i < argumentLength; i++) {
        if (originalArgumentTypes[i] != alternateArgumentTypes[i]) {
          scope.problemReporter().unnecessaryCast((CastExpression) arguments[i]);
        }
      }
    }
  }
Пример #11
0
  /** Check binary operator casted arguments */
  public static void checkNeedForArgumentCasts(
      BlockScope scope,
      int operator,
      int operatorSignature,
      Expression left,
      int leftTypeId,
      boolean leftIsCast,
      Expression right,
      int rightTypeId,
      boolean rightIsCast) {
    if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
        == ProblemSeverities.Ignore) return;

    // check need for left operand cast
    int alternateLeftTypeId = leftTypeId;
    if (leftIsCast) {
      if ((left.bits & ASTNode.UnnecessaryCast) == 0 && left.resolvedType.isBaseType()) {
        // narrowing conversion on base type may change value, thus necessary
        leftIsCast = false;
      } else {
        TypeBinding alternateLeftType = ((CastExpression) left).expression.resolvedType;
        if (alternateLeftType == null) return; // cannot do better
        if ((alternateLeftTypeId = alternateLeftType.id) == leftTypeId) { // obvious identity cast
          scope.problemReporter().unnecessaryCast((CastExpression) left);
          leftIsCast = false;
        } else if (alternateLeftTypeId == TypeIds.T_null) {
          alternateLeftTypeId = leftTypeId; // tolerate null argument cast
          leftIsCast = false;
        }
      }
    }
    // check need for right operand cast
    int alternateRightTypeId = rightTypeId;
    if (rightIsCast) {
      if ((right.bits & ASTNode.UnnecessaryCast) == 0 && right.resolvedType.isBaseType()) {
        // narrowing conversion on base type may change value, thus necessary
        rightIsCast = false;
      } else {
        TypeBinding alternateRightType = ((CastExpression) right).expression.resolvedType;
        if (alternateRightType == null) return; // cannot do better
        if ((alternateRightTypeId = alternateRightType.id)
            == rightTypeId) { // obvious identity cast
          scope.problemReporter().unnecessaryCast((CastExpression) right);
          rightIsCast = false;
        } else if (alternateRightTypeId == TypeIds.T_null) {
          alternateRightTypeId = rightTypeId; // tolerate null argument cast
          rightIsCast = false;
        }
      }
    }
    if (leftIsCast || rightIsCast) {
      if (alternateLeftTypeId > 15
          || alternateRightTypeId > 15) { // must convert String + Object || Object + String
        if (alternateLeftTypeId == TypeIds.T_JavaLangString) {
          alternateRightTypeId = TypeIds.T_JavaLangObject;
        } else if (alternateRightTypeId == TypeIds.T_JavaLangString) {
          alternateLeftTypeId = TypeIds.T_JavaLangObject;
        } else {
          return; // invalid operator
        }
      }
      int alternateOperatorSignature =
          OperatorExpression.OperatorSignatures[operator][
              (alternateLeftTypeId << 4) + alternateRightTypeId];
      // (cast)  left   Op (cast)  right --> result
      //  1111   0000       1111   0000     1111
      //  <<16   <<12       <<8    <<4       <<0
      final int CompareMASK = (0xF << 16) + (0xF << 8) + 0xF; // mask hiding compile-time types
      if ((operatorSignature & CompareMASK)
          == (alternateOperatorSignature & CompareMASK)) { // same promotions and result
        if (leftIsCast) scope.problemReporter().unnecessaryCast((CastExpression) left);
        if (rightIsCast) scope.problemReporter().unnecessaryCast((CastExpression) right);
      }
    }
  }