| /* |
| * Copyright 2003-2011 Dave Griffith, Bas Leijdekkers |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.siyeh.ig.bitwise; |
| |
| import com.intellij.psi.*; |
| import com.intellij.psi.tree.IElementType; |
| import com.intellij.psi.util.ConstantExpressionUtil; |
| import com.intellij.psi.util.PsiUtil; |
| import com.siyeh.InspectionGadgetsBundle; |
| import com.siyeh.ig.BaseInspection; |
| import com.siyeh.ig.BaseInspectionVisitor; |
| import com.siyeh.ig.psiutils.ComparisonUtils; |
| import com.siyeh.ig.psiutils.ParenthesesUtils; |
| import org.jetbrains.annotations.NotNull; |
| |
| public class IncompatibleMaskInspection extends BaseInspection { |
| |
| @Override |
| @NotNull |
| public String getID() { |
| return "IncompatibleBitwiseMaskOperation"; |
| } |
| |
| @Override |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message( |
| "incompatible.mask.operation.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| public String buildErrorString(Object... infos) { |
| final PsiBinaryExpression binaryExpression = |
| (PsiBinaryExpression)infos[0]; |
| final IElementType tokenType = binaryExpression.getOperationTokenType(); |
| if (tokenType.equals(JavaTokenType.EQEQ)) { |
| return InspectionGadgetsBundle.message( |
| "incompatible.mask.operation.problem.descriptor.always.false"); |
| } |
| else { |
| return InspectionGadgetsBundle.message( |
| "incompatible.mask.operation.problem.descriptor.always.true"); |
| } |
| } |
| |
| @Override |
| public boolean isEnabledByDefault() { |
| return true; |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new IncompatibleMaskVisitor(); |
| } |
| |
| private static class IncompatibleMaskVisitor extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitBinaryExpression( |
| @NotNull PsiBinaryExpression expression) { |
| super.visitBinaryExpression(expression); |
| final PsiExpression rhs = expression.getROperand(); |
| if (!ComparisonUtils.isEqualityComparison(expression)) { |
| return; |
| } |
| final PsiType expressionType = expression.getType(); |
| if (expressionType == null) { |
| return; |
| } |
| final PsiExpression strippedRhs = |
| ParenthesesUtils.stripParentheses(rhs); |
| if (strippedRhs == null) { |
| return; |
| } |
| final PsiExpression lhs = expression.getLOperand(); |
| final PsiExpression strippedLhs = |
| ParenthesesUtils.stripParentheses(lhs); |
| if (strippedLhs == null) { |
| return; |
| } |
| if (isConstantMask(strippedLhs) && |
| PsiUtil.isConstantExpression(strippedRhs)) { |
| if (isIncompatibleMask((PsiBinaryExpression)strippedLhs, |
| strippedRhs)) { |
| registerError(expression, expression); |
| } |
| } |
| else if (isConstantMask(strippedRhs) && |
| PsiUtil.isConstantExpression(strippedLhs)) { |
| if (isIncompatibleMask((PsiBinaryExpression)strippedRhs, |
| strippedLhs)) { |
| registerError(expression, expression); |
| } |
| } |
| } |
| |
| private static boolean isIncompatibleMask( |
| PsiBinaryExpression maskExpression, |
| PsiExpression constantExpression) { |
| final IElementType tokenType = |
| maskExpression.getOperationTokenType(); |
| final Object constantValue = |
| ConstantExpressionUtil.computeCastTo(constantExpression, |
| PsiType.LONG); |
| if (constantValue == null) { |
| return false; |
| } |
| final long constantLongValue = ((Long)constantValue).longValue(); |
| final PsiExpression maskRhs = maskExpression.getROperand(); |
| final PsiExpression maskLhs = maskExpression.getLOperand(); |
| final long constantMaskValue; |
| if (PsiUtil.isConstantExpression(maskRhs)) { |
| final Object rhsValue = |
| ConstantExpressionUtil.computeCastTo(maskRhs, |
| PsiType.LONG); |
| if (rhsValue == null) { |
| return false; // Might indeed be the case with "null" literal |
| // whoes constant value evaluates to null. Check out (a|null) case. |
| } |
| constantMaskValue = ((Long)rhsValue).longValue(); |
| } |
| else { |
| final Object lhsValue = |
| ConstantExpressionUtil.computeCastTo(maskLhs, |
| PsiType.LONG); |
| if (lhsValue == null) { |
| return false; |
| } |
| constantMaskValue = ((Long)lhsValue).longValue(); |
| } |
| |
| if (tokenType.equals(JavaTokenType.OR)) { |
| if ((constantMaskValue | constantLongValue) != constantLongValue) { |
| return true; |
| } |
| } |
| if (tokenType.equals(JavaTokenType.AND)) { |
| if ((constantMaskValue | constantLongValue) != constantMaskValue) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| private static boolean isConstantMask(PsiExpression expression) { |
| if (expression == null) { |
| return false; |
| } |
| if (!(expression instanceof PsiBinaryExpression)) { |
| return false; |
| } |
| final PsiBinaryExpression binaryExpression = |
| (PsiBinaryExpression)expression; |
| final IElementType tokenType = |
| binaryExpression.getOperationTokenType(); |
| if (!tokenType.equals(JavaTokenType.OR) && |
| !tokenType.equals(JavaTokenType.AND)) { |
| return false; |
| } |
| final PsiExpression rhs = binaryExpression.getROperand(); |
| if (PsiUtil.isConstantExpression(rhs)) { |
| return true; |
| } |
| final PsiExpression lhs = binaryExpression.getLOperand(); |
| return PsiUtil.isConstantExpression(lhs); |
| } |
| } |
| } |