| /* |
| * Copyright 2003-2013 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.ProblemDescriptor; |
| import com.intellij.openapi.project.Project; |
| import com.intellij.psi.*; |
| import com.intellij.psi.util.PsiUtil; |
| import com.intellij.util.IncorrectOperationException; |
| import com.siyeh.InspectionGadgetsBundle; |
| import com.siyeh.ig.BaseInspection; |
| import com.siyeh.ig.BaseInspectionVisitor; |
| import com.siyeh.ig.InspectionGadgetsFix; |
| import com.siyeh.ig.PsiReplacementUtil; |
| import com.siyeh.ig.psiutils.ExpressionUtils; |
| import com.siyeh.ig.psiutils.ParenthesesUtils; |
| import com.siyeh.ig.psiutils.TypeUtils; |
| import org.jetbrains.annotations.NonNls; |
| import org.jetbrains.annotations.NotNull; |
| |
| public class TrivialStringConcatenationInspection extends BaseInspection { |
| |
| @Override |
| @NotNull |
| public String getID() { |
| return "ConcatenationWithEmptyString"; |
| } |
| |
| @Override |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message("trivial.string.concatenation.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| public String buildErrorString(Object... infos) { |
| return InspectionGadgetsBundle.message("trivial.string.concatenation.problem.descriptor"); |
| } |
| |
| @NonNls |
| static String calculateReplacementExpression(PsiLiteralExpression expression) { |
| final PsiElement parent = ParenthesesUtils.getParentSkipParentheses(expression); |
| if (!(parent instanceof PsiPolyadicExpression)) { |
| return null; |
| } |
| if (parent instanceof PsiBinaryExpression) { |
| final PsiBinaryExpression binaryExpression = (PsiBinaryExpression)parent; |
| final PsiExpression lOperand = ParenthesesUtils.stripParentheses(binaryExpression.getLOperand()); |
| final PsiExpression rOperand = ParenthesesUtils.stripParentheses(binaryExpression.getROperand()); |
| final PsiExpression replacement; |
| if (ExpressionUtils.isEmptyStringLiteral(lOperand)) { |
| replacement = rOperand; |
| } |
| else { |
| replacement = lOperand; |
| } |
| return replacement == null ? "" : buildReplacement(replacement, false); |
| } |
| final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression)parent; |
| final PsiExpression[] operands = polyadicExpression.getOperands(); |
| final PsiClassType stringType = TypeUtils.getStringType(expression); |
| boolean seenString = false; |
| boolean seenEmpty = false; |
| boolean replaced = false; |
| PsiExpression operandToReplace = null; |
| final StringBuilder text = new StringBuilder(); |
| for (PsiExpression operand : operands) { |
| if (operandToReplace != null && !replaced) { |
| if (ExpressionUtils.hasStringType(operand)) { |
| seenString = true; |
| } |
| if (text.length() > 0) { |
| text.append(" + "); |
| } |
| text.append(buildReplacement(operandToReplace, seenString)); |
| text.append(" + "); |
| text.append(operand.getText()); |
| replaced = true; |
| continue; |
| } |
| if (ParenthesesUtils.stripParentheses(operand) == expression) { |
| seenEmpty = true; |
| continue; |
| } |
| if (seenEmpty && !replaced) { |
| operandToReplace = operand; |
| continue; |
| } |
| if (stringType.equals(operand.getType())) { |
| seenString = true; |
| } |
| if (text.length() > 0) { |
| text.append(" + "); |
| } |
| text.append(operand.getText()); |
| } |
| if (!replaced && operandToReplace != null) { |
| text.append(" + "); |
| text.append(buildReplacement(operandToReplace, seenString)); |
| } |
| return text.toString(); |
| } |
| |
| @NonNls |
| static String buildReplacement(@NotNull PsiExpression operandToReplace, boolean seenString) { |
| if (ExpressionUtils.isNullLiteral(operandToReplace)) { |
| if (seenString) { |
| return "null"; |
| } |
| else { |
| return "String.valueOf((Object)null)"; |
| } |
| } |
| if (seenString || ExpressionUtils.hasStringType(operandToReplace)) { |
| return operandToReplace.getText(); |
| } |
| return "String.valueOf(" + operandToReplace.getText() + ')'; |
| } |
| |
| @Override |
| public InspectionGadgetsFix buildFix(Object... infos) { |
| return new UnnecessaryTemporaryObjectFix((PsiLiteralExpression)infos[0]); |
| } |
| |
| private static class UnnecessaryTemporaryObjectFix extends InspectionGadgetsFix { |
| |
| private final String m_name; |
| |
| private UnnecessaryTemporaryObjectFix(PsiLiteralExpression expression) { |
| m_name = InspectionGadgetsBundle.message("string.replace.quickfix", calculateReplacementExpression(expression)); |
| } |
| |
| @Override |
| @NotNull |
| public String getName() { |
| return m_name; |
| } |
| |
| @NotNull |
| @Override |
| public String getFamilyName() { |
| return "Replace concatenation"; |
| } |
| |
| @Override |
| public void doFix(Project project, ProblemDescriptor descriptor) throws IncorrectOperationException { |
| final PsiLiteralExpression expression = (PsiLiteralExpression)descriptor.getPsiElement(); |
| final PsiElement parent = ParenthesesUtils.getParentSkipParentheses(expression); |
| if (!(parent instanceof PsiExpression)) { |
| return; |
| } |
| final String newExpression = calculateReplacementExpression(expression); |
| PsiReplacementUtil.replaceExpression((PsiExpression)parent, newExpression); |
| } |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new TrivialStringConcatenationVisitor(); |
| } |
| |
| private static class TrivialStringConcatenationVisitor extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitPolyadicExpression(PsiPolyadicExpression expression) { |
| super.visitPolyadicExpression(expression); |
| if (!ExpressionUtils.hasStringType(expression)) { |
| return; |
| } |
| final PsiExpression[] operands = expression.getOperands(); |
| for (PsiExpression operand : operands) { |
| operand = ParenthesesUtils.stripParentheses(operand); |
| if (operand == null) { |
| return; |
| } |
| if (!ExpressionUtils.isEmptyStringLiteral(operand)) { |
| continue; |
| } |
| if (PsiUtil.isConstantExpression(expression)) { |
| return; |
| } |
| registerError(operand, operand); |
| } |
| } |
| } |
| } |