| /* |
| * Copyright 2003-2007 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.performance; |
| |
| import com.intellij.psi.*; |
| import com.intellij.psi.util.PsiTreeUtil; |
| import com.siyeh.InspectionGadgetsBundle; |
| import com.siyeh.ig.BaseInspection; |
| import com.siyeh.ig.BaseInspectionVisitor; |
| import com.siyeh.ig.psiutils.ControlFlowUtils; |
| import org.jetbrains.annotations.NotNull; |
| |
| public class ObjectAllocationInLoopInspection extends BaseInspection { |
| |
| @Override |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message( |
| "object.allocation.in.loop.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| protected String buildErrorString(Object... infos) { |
| return InspectionGadgetsBundle.message( |
| "object.allocation.in.loop.problem.descriptor"); |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new ObjectAllocationInLoopsVisitor(); |
| } |
| |
| private static class ObjectAllocationInLoopsVisitor |
| extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitNewExpression(@NotNull PsiNewExpression expression) { |
| super.visitNewExpression(expression); |
| if (!ControlFlowUtils.isInLoop(expression)) { |
| return; |
| } |
| if (ControlFlowUtils.isInExitStatement(expression)) { |
| return; |
| } |
| final PsiStatement newExpressionStatement = |
| PsiTreeUtil.getParentOfType(expression, PsiStatement.class); |
| if (newExpressionStatement == null) { |
| return; |
| } |
| final PsiStatement parentStatement = |
| PsiTreeUtil.getParentOfType(newExpressionStatement, |
| PsiStatement.class); |
| if (!ControlFlowUtils.statementMayCompleteNormally( |
| parentStatement)) { |
| return; |
| } |
| if (isAllocatedOnlyOnce(expression)) { |
| return; |
| } |
| registerNewExpressionError(expression); |
| } |
| |
| private static boolean isAllocatedOnlyOnce( |
| PsiNewExpression expression) { |
| final PsiElement parent = expression.getParent(); |
| if (!(parent instanceof PsiAssignmentExpression)) { |
| return false; |
| } |
| final PsiAssignmentExpression assignmentExpression = |
| (PsiAssignmentExpression)parent; |
| final PsiExpression lExpression = |
| assignmentExpression.getLExpression(); |
| if (!(lExpression instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| final PsiIfStatement ifStatement = |
| PsiTreeUtil.getParentOfType(assignmentExpression, |
| PsiIfStatement.class); |
| if (ifStatement == null) { |
| return false; |
| } |
| final PsiExpression condition = ifStatement.getCondition(); |
| if (!(condition instanceof PsiBinaryExpression)) { |
| return false; |
| } |
| final PsiBinaryExpression binaryExpression = |
| (PsiBinaryExpression)condition; |
| if (binaryExpression.getOperationTokenType() != |
| JavaTokenType.EQEQ) { |
| return false; |
| } |
| final PsiReferenceExpression referenceExpression = |
| (PsiReferenceExpression)lExpression; |
| final PsiExpression lhs = binaryExpression.getLOperand(); |
| final PsiExpression rhs = binaryExpression.getROperand(); |
| if (lhs instanceof PsiLiteralExpression) { |
| if (!"null".equals(lhs.getText())) { |
| return false; |
| } |
| if (!(rhs instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| return referenceExpression.getText().equals(rhs.getText()); |
| } |
| else if (rhs instanceof PsiLiteralExpression) { |
| if (!"null".equals(rhs.getText())) { |
| return false; |
| } |
| if (!(lhs instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| return referenceExpression.getText().equals(lhs.getText()); |
| } |
| else { |
| return false; |
| } |
| } |
| } |
| } |