| /* |
| * 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.bugs; |
| |
| import com.intellij.psi.*; |
| import com.intellij.psi.tree.IElementType; |
| import com.intellij.psi.util.PsiTreeUtil; |
| 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.VariableAccessUtils; |
| import org.jetbrains.annotations.NonNls; |
| import org.jetbrains.annotations.NotNull; |
| |
| public class MismatchedArrayReadWriteInspection extends BaseInspection { |
| |
| @Override |
| @NotNull |
| public String getID() { |
| return "MismatchedReadAndWriteOfArray"; |
| } |
| |
| @Override |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message( |
| "mismatched.read.write.array.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| public String buildErrorString(Object... infos) { |
| final boolean written = ((Boolean)infos[0]).booleanValue(); |
| if (written) { |
| return InspectionGadgetsBundle.message( |
| "mismatched.read.write.array.problem.descriptor.write.not.read"); |
| } |
| else { |
| return InspectionGadgetsBundle.message( |
| "mismatched.read.write.array.problem.descriptor.read.not.write"); |
| } |
| } |
| |
| @Override |
| public boolean isEnabledByDefault() { |
| return true; |
| } |
| |
| @Override |
| public boolean runForWholeFile() { |
| return true; |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new MismatchedArrayReadWriteVisitor(); |
| } |
| |
| private static class MismatchedArrayReadWriteVisitor |
| extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitField(@NotNull PsiField field) { |
| super.visitField(field); |
| if (!field.hasModifierProperty(PsiModifier.PRIVATE)) { |
| return; |
| } |
| final PsiClass containingClass = PsiUtil.getTopLevelClass(field); |
| if (!checkVariable(field, containingClass)) { |
| return; |
| } |
| final boolean written = |
| arrayContentsAreWritten(field, containingClass); |
| final boolean read = arrayContentsAreRead(field, containingClass); |
| if (written == read) { |
| return; |
| } |
| registerFieldError(field, Boolean.valueOf(written)); |
| } |
| |
| @Override |
| public void visitLocalVariable( |
| @NotNull PsiLocalVariable variable) { |
| super.visitLocalVariable(variable); |
| final PsiCodeBlock codeBlock = |
| PsiTreeUtil.getParentOfType(variable, PsiCodeBlock.class); |
| if (!checkVariable(variable, codeBlock)) { |
| return; |
| } |
| final boolean written = |
| arrayContentsAreWritten(variable, codeBlock); |
| final boolean read = arrayContentsAreRead(variable, codeBlock); |
| if (written == read) { |
| return; |
| } |
| registerVariableError(variable, Boolean.valueOf(written)); |
| } |
| |
| private static boolean checkVariable(PsiVariable variable, |
| PsiElement context) { |
| if (context == null) { |
| return false; |
| } |
| final PsiType type = variable.getType(); |
| if (type.getArrayDimensions() == 0) { |
| return false; |
| } |
| if (VariableAccessUtils.variableIsAssigned(variable, context)) { |
| return false; |
| } |
| if (VariableAccessUtils.variableIsAssignedFrom(variable, context)) { |
| return false; |
| } |
| if (VariableAccessUtils.variableIsReturned(variable, context)) { |
| return false; |
| } |
| return !VariableAccessUtils.variableIsUsedInArrayInitializer( |
| variable, context); |
| } |
| |
| private static boolean arrayContentsAreWritten(PsiVariable variable, |
| PsiElement context) { |
| if (VariableAccessUtils.arrayContentsAreAssigned(variable, context)) { |
| return true; |
| } |
| final PsiExpression initializer = variable.getInitializer(); |
| if (initializer != null && !isDefaultArrayInitializer(initializer)) { |
| return true; |
| } |
| return variableIsWritten(variable, context); |
| } |
| |
| private static boolean arrayContentsAreRead(PsiVariable variable, |
| PsiElement context) { |
| if (VariableAccessUtils.arrayContentsAreAccessed(variable, context)) { |
| return true; |
| } |
| return variableIsRead(variable, context); |
| } |
| |
| private static boolean isDefaultArrayInitializer( |
| PsiExpression initializer) { |
| if (initializer instanceof PsiNewExpression) { |
| final PsiNewExpression newExpression = |
| (PsiNewExpression)initializer; |
| final PsiArrayInitializerExpression arrayInitializer = |
| newExpression.getArrayInitializer(); |
| return arrayInitializer == null || |
| isDefaultArrayInitializer(arrayInitializer); |
| } |
| else if (initializer instanceof PsiArrayInitializerExpression) { |
| final PsiArrayInitializerExpression arrayInitializerExpression = |
| (PsiArrayInitializerExpression)initializer; |
| final PsiExpression[] initializers = |
| arrayInitializerExpression.getInitializers(); |
| return initializers.length == 0; |
| } |
| return false; |
| } |
| |
| public static boolean variableIsWritten(@NotNull PsiVariable variable, @NotNull PsiElement context) { |
| final VariableReadWriteVisitor visitor = |
| new VariableReadWriteVisitor(variable, true); |
| context.accept(visitor); |
| return visitor.isPassed(); |
| } |
| |
| public static boolean variableIsRead(@NotNull PsiVariable variable, @NotNull PsiElement context) { |
| final VariableReadWriteVisitor visitor = |
| new VariableReadWriteVisitor(variable, false); |
| context.accept(visitor); |
| return visitor.isPassed(); |
| } |
| |
| static class VariableReadWriteVisitor extends JavaRecursiveElementVisitor { |
| |
| @NotNull |
| private final PsiVariable variable; |
| private final boolean write; |
| private boolean passed = false; |
| |
| VariableReadWriteVisitor(@NotNull PsiVariable variable, boolean write) { |
| this.variable = variable; |
| this.write = write; |
| } |
| |
| @Override |
| public void visitElement(@NotNull PsiElement element) { |
| if (!passed) { |
| super.visitElement(element); |
| } |
| } |
| |
| @Override |
| public void visitBinaryExpression(PsiBinaryExpression expression) { |
| super.visitBinaryExpression(expression); |
| if (write || passed) { |
| return; |
| } |
| final IElementType tokenType = expression.getOperationTokenType(); |
| if (!JavaTokenType.EQEQ.equals(tokenType) && !JavaTokenType.NE.equals(tokenType)) { |
| return; |
| } |
| final PsiExpression lhs = expression.getLOperand(); |
| if (!(lhs instanceof PsiBinaryExpression)) { |
| if (VariableAccessUtils.mayEvaluateToVariable(lhs, variable)) { |
| passed = true; |
| } |
| } |
| final PsiExpression rhs = expression.getROperand(); |
| if (!(rhs instanceof PsiBinaryExpression)) { |
| if (VariableAccessUtils.mayEvaluateToVariable(rhs, variable)) { |
| passed = true; |
| } |
| } |
| } |
| |
| @Override |
| public void visitMethodCallExpression( |
| @NotNull PsiMethodCallExpression call) { |
| if (passed) { |
| return; |
| } |
| super.visitMethodCallExpression(call); |
| final PsiExpressionList argumentList = call.getArgumentList(); |
| final PsiExpression[] arguments = argumentList.getExpressions(); |
| for (int i = 0; i < arguments.length; i++) { |
| final PsiExpression argument = arguments[i]; |
| if (VariableAccessUtils.mayEvaluateToVariable(argument, |
| variable)) { |
| if (write && i == 0 && isCallToSystemArraycopy(call)) { |
| return; |
| } |
| if (!write && i == 2 && isCallToSystemArraycopy(call)) { |
| return; |
| } |
| passed = true; |
| } |
| } |
| } |
| |
| private static boolean isCallToSystemArraycopy( |
| PsiMethodCallExpression call) { |
| final PsiReferenceExpression methodExpression = |
| call.getMethodExpression(); |
| @NonNls final String name = |
| methodExpression.getReferenceName(); |
| if (!"arraycopy".equals(name)) { |
| return false; |
| } |
| final PsiExpression qualifier = |
| methodExpression.getQualifierExpression(); |
| if (!(qualifier instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| final PsiReferenceExpression referenceExpression = |
| (PsiReferenceExpression)qualifier; |
| final PsiElement element = |
| referenceExpression.resolve(); |
| if (!(element instanceof PsiClass)) { |
| return false; |
| } |
| final PsiClass aClass = (PsiClass)element; |
| final String qualifiedName = |
| aClass.getQualifiedName(); |
| return "java.lang.System".equals(qualifiedName); |
| } |
| |
| @Override |
| public void visitNewExpression( |
| @NotNull PsiNewExpression newExpression) { |
| if (passed) { |
| return; |
| } |
| super.visitNewExpression(newExpression); |
| final PsiExpressionList argumentList = |
| newExpression.getArgumentList(); |
| if (argumentList == null) { |
| return; |
| } |
| final PsiExpression[] arguments = argumentList.getExpressions(); |
| for (final PsiExpression argument : arguments) { |
| if (VariableAccessUtils.mayEvaluateToVariable(argument, |
| variable)) { |
| passed = true; |
| } |
| } |
| } |
| |
| public boolean isPassed() { |
| return passed; |
| } |
| } |
| } |
| } |
