| /* |
| * Copyright 2003-2012 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.codeInspection.ui.SingleCheckboxOptionsPanel; |
| import com.intellij.psi.*; |
| import com.intellij.psi.tree.IElementType; |
| 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 com.siyeh.ig.psiutils.ExpressionUtils; |
| import com.siyeh.ig.psiutils.TypeUtils; |
| import com.siyeh.ig.psiutils.VariableAccessUtils; |
| import org.jetbrains.annotations.NotNull; |
| |
| import javax.swing.JComponent; |
| |
| public class StringConcatenationInLoopsInspection extends BaseInspection { |
| |
| @SuppressWarnings("PublicField") |
| public boolean m_ignoreUnlessAssigned = true; |
| |
| @Override |
| @NotNull |
| public String getID() { |
| return "StringContatenationInLoop"; |
| } |
| |
| @Override |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message("string.concatenation.in.loops.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| protected String buildErrorString(Object... infos) { |
| return InspectionGadgetsBundle.message("string.concatenation.in.loops.problem.descriptor"); |
| } |
| |
| @Override |
| public JComponent createOptionsPanel() { |
| return new SingleCheckboxOptionsPanel(InspectionGadgetsBundle.message("string.concatenation.in.loops.only.option"), |
| this, "m_ignoreUnlessAssigned"); |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new StringConcatenationInLoopsVisitor(); |
| } |
| |
| private class StringConcatenationInLoopsVisitor extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitPolyadicExpression(PsiPolyadicExpression expression) { |
| super.visitPolyadicExpression(expression); |
| final PsiExpression[] operands = expression.getOperands(); |
| if (operands.length <= 1) { |
| return; |
| } |
| final IElementType tokenType = expression.getOperationTokenType(); |
| if (!tokenType.equals(JavaTokenType.PLUS)) { |
| return; |
| } |
| final PsiType type = expression.getType(); |
| if (!TypeUtils.isJavaLangString(type)) { |
| return; |
| } |
| if (!ControlFlowUtils.isInLoop(expression)) { |
| return; |
| } |
| if (ControlFlowUtils.isInExitStatement(expression)) { |
| return; |
| } |
| if (ExpressionUtils.isEvaluatedAtCompileTime(expression)) { |
| return; |
| } |
| if (containingStatementExits(expression)) { |
| return; |
| } |
| if (m_ignoreUnlessAssigned && !isAppendedRepeatedly(expression)) { |
| return; |
| } |
| final PsiJavaToken sign = expression.getTokenBeforeOperand(operands[1]); |
| registerError(sign); |
| } |
| |
| @Override |
| public void visitAssignmentExpression(@NotNull PsiAssignmentExpression expression) { |
| super.visitAssignmentExpression(expression); |
| if (expression.getRExpression() == null) { |
| return; |
| } |
| final PsiJavaToken sign = expression.getOperationSign(); |
| final IElementType tokenType = sign.getTokenType(); |
| if (!tokenType.equals(JavaTokenType.PLUSEQ)) { |
| return; |
| } |
| PsiExpression lhs = expression.getLExpression(); |
| final PsiType type = lhs.getType(); |
| if (type == null) { |
| return; |
| } |
| if (!TypeUtils.isJavaLangString(type)) { |
| return; |
| } |
| if (!ControlFlowUtils.isInLoop(expression)) { |
| return; |
| } |
| if (ControlFlowUtils.isInExitStatement(expression)) { |
| return; |
| } |
| if (containingStatementExits(expression)) { |
| return; |
| } |
| if (m_ignoreUnlessAssigned) { |
| while (lhs instanceof PsiParenthesizedExpression) { |
| final PsiParenthesizedExpression parenthesizedExpression = (PsiParenthesizedExpression)lhs; |
| lhs = parenthesizedExpression.getExpression(); |
| } |
| if (!(lhs instanceof PsiReferenceExpression)) { |
| return; |
| } |
| } |
| registerError(sign); |
| } |
| |
| private boolean containingStatementExits(PsiElement element) { |
| final PsiStatement newExpressionStatement = PsiTreeUtil.getParentOfType(element, PsiStatement.class); |
| if (newExpressionStatement == null) { |
| return containingStatementExits(element); |
| } |
| final PsiStatement parentStatement = PsiTreeUtil.getParentOfType(newExpressionStatement, PsiStatement.class); |
| return !ControlFlowUtils.statementMayCompleteNormally(parentStatement); |
| } |
| |
| private boolean isAppendedRepeatedly(PsiExpression expression) { |
| PsiElement parent = expression.getParent(); |
| while (parent instanceof PsiParenthesizedExpression || parent instanceof PsiPolyadicExpression) { |
| parent = parent.getParent(); |
| } |
| if (!(parent instanceof PsiAssignmentExpression)) { |
| return false; |
| } |
| final PsiAssignmentExpression assignmentExpression = (PsiAssignmentExpression)parent; |
| PsiExpression lhs = assignmentExpression.getLExpression(); |
| while (lhs instanceof PsiParenthesizedExpression) { |
| final PsiParenthesizedExpression parenthesizedExpression = (PsiParenthesizedExpression)lhs; |
| lhs = parenthesizedExpression.getExpression(); |
| } |
| if (!(lhs instanceof PsiReferenceExpression)) { |
| return false; |
| } |
| if (assignmentExpression.getOperationTokenType() == JavaTokenType.PLUSEQ) { |
| return true; |
| } |
| final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)lhs; |
| final PsiElement element = referenceExpression.resolve(); |
| if (!(element instanceof PsiVariable)) { |
| return false; |
| } |
| final PsiVariable variable = (PsiVariable)element; |
| final PsiExpression rhs = assignmentExpression.getRExpression(); |
| return rhs != null && VariableAccessUtils.variableIsUsed(variable, rhs); |
| } |
| } |
| } |