/*
* Copyright 2011-2015 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.controlflow;
import com.intellij.codeInspection.CleanupLocalInspectionTool;
import com.intellij.codeInspection.ProblemDescriptor;
import com.intellij.openapi.project.Project;
import com.intellij.psi.*;
import com.intellij.psi.tree.IElementType;
import com.intellij.psi.util.PsiUtil;
import com.siyeh.HardcodedMethodConstants;
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 org.jetbrains.annotations.Nls;
import org.jetbrains.annotations.NonNls;
import org.jetbrains.annotations.NotNull;
public class SimplifiableEqualsExpressionInspection extends BaseInspection implements CleanupLocalInspectionTool {
@Nls
@NotNull
@Override
public String getDisplayName() {
return InspectionGadgetsBundle.message("simplifiable.equals.expression.display.name");
}
@NotNull
@Override
protected String buildErrorString(Object... infos) {
return InspectionGadgetsBundle.message("simplifiable.equals.expression.problem.descriptor", infos[0]);
}
@Override
protected InspectionGadgetsFix buildFix(Object... infos) {
return new SimplifiableEqualsExpressionFix((String)infos[0]);
}
private static class SimplifiableEqualsExpressionFix extends InspectionGadgetsFix {
private final String myMethodName;
public SimplifiableEqualsExpressionFix(String methodName) {
myMethodName = methodName;
}
@NotNull
@Override
public String getName() {
return InspectionGadgetsBundle.message("simplifiable.equals.expression.quickfix", myMethodName);
}
@NotNull
@Override
public String getFamilyName() {
return "Simplify";
}
@Override
protected void doFix(Project project, ProblemDescriptor descriptor) {
final PsiElement element = descriptor.getPsiElement();
final PsiElement parent = ParenthesesUtils.getParentSkipParentheses(element);
if (!(parent instanceof PsiPolyadicExpression)) {
return;
}
final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression)parent;
final PsiExpression[] operands = polyadicExpression.getOperands();
if (operands.length != 2) {
return;
}
PsiExpression operand = ParenthesesUtils.stripParentheses(operands[1]);
@NonNls final StringBuilder newExpressionText = new StringBuilder();
if (operand instanceof PsiPrefixExpression) {
final PsiPrefixExpression prefixExpression = (PsiPrefixExpression)operand;
if (!JavaTokenType.EXCL.equals(prefixExpression.getOperationTokenType())) {
return;
}
newExpressionText.append('!');
operand = ParenthesesUtils.stripParentheses(prefixExpression.getOperand());
}
if (!(operand instanceof PsiMethodCallExpression)) {
return;
}
final PsiMethodCallExpression methodCallExpression = (PsiMethodCallExpression)operand;
final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression();
final String referenceName = methodExpression.getReferenceName();
final PsiExpression qualifier = methodExpression.getQualifierExpression();
if (qualifier == null) {
return;
}
final PsiExpressionList argumentList = methodCallExpression.getArgumentList();
final PsiExpression[] arguments = argumentList.getExpressions();
if (arguments.length != 1) {
return;
}
final PsiExpression argument = arguments[0];
final PsiType type = argument.getType();
if (PsiType.BOOLEAN.equals(type)) {
final Object value = ExpressionUtils.computeConstantExpression(argument);
if (Boolean.TRUE.equals(value)) {
newExpressionText.append("java.lang.Boolean.TRUE");
}
else if (Boolean.FALSE.equals(value)) {
newExpressionText.append("java.lang.Boolean.FALSE");
}
else {
newExpressionText.append("java.lang.Boolean.valueOf(").append(argument.getText()).append(')');
}
}
else if (PsiType.BYTE.equals(type)) {
newExpressionText.append("java.lang.Byte.valueOf(").append(argument.getText()).append(')');
}
else if (PsiType.SHORT.equals(type)) {
newExpressionText.append("java.lang.Short.valueOf(").append(argument.getText()).append(')');
}
else if (PsiType.INT.equals(type)) {
newExpressionText.append("java.lang.Integer.valueOf(").append(argument.getText()).append(')');
}
else if (PsiType.LONG.equals(type)) {
newExpressionText.append("java.lang.Long.valueOf(").append(argument.getText()).append(')');
}
else if (PsiType.FLOAT.equals(type)) {
newExpressionText.append("java.lang.Float.valueOf(").append(argument.getText()).append(')');
}
else if (PsiType.DOUBLE.equals(type)) {
newExpressionText.append("java.lang.Double.valueOf(").append(argument.getText()).append(')');
}
else {
newExpressionText.append(argument.getText());
}
newExpressionText.append('.').append(referenceName).append('(').append(qualifier.getText()).append(')');
PsiReplacementUtil.replaceExpression(polyadicExpression, newExpressionText.toString());
}
}
@Override
public BaseInspectionVisitor buildVisitor() {
return new SimplifiableEqualsExpressionVisitor();
}
private static class SimplifiableEqualsExpressionVisitor extends BaseInspectionVisitor {
@Override
public void visitPolyadicExpression(PsiPolyadicExpression expression) {
super.visitPolyadicExpression(expression);
final IElementType tokenType = expression.getOperationTokenType();
if (JavaTokenType.ANDAND.equals(tokenType)) {
final PsiExpression[] operands = expression.getOperands();
if (operands.length != 2) {
return;
}
final PsiExpression lhs = operands[0];
final PsiVariable variable = ExpressionUtils.getVariableFromNullComparison(lhs, false);
if (variable == null) {
return;
}
final PsiExpression rhs = ParenthesesUtils.stripParentheses(operands[1]);
if (!isEqualsConstant(rhs, variable)) {
return;
}
registerError(lhs, getMethodName((PsiMethodCallExpression)rhs));
}
else if (JavaTokenType.OROR.equals(tokenType)) {
final PsiExpression[] operands = expression.getOperands();
if (operands.length != 2) {
return;
}
final PsiExpression lhs = operands[0];
final PsiVariable variable = ExpressionUtils.getVariableFromNullComparison(lhs, true);
if (variable == null) {
return;
}
final PsiExpression rhs = ParenthesesUtils.stripParentheses(operands[1]);
if (!(rhs instanceof PsiPrefixExpression)) {
return;
}
final PsiPrefixExpression prefixExpression = (PsiPrefixExpression)rhs;
if (!JavaTokenType.EXCL.equals(prefixExpression.getOperationTokenType())) {
return;
}
final PsiExpression operand = ParenthesesUtils.stripParentheses(prefixExpression.getOperand());
if (!isEqualsConstant(operand, variable)) {
return;
}
registerError(lhs, getMethodName((PsiMethodCallExpression)operand));
}
}
private static String getMethodName(PsiMethodCallExpression methodCallExpression) {
final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression();
return methodExpression.getReferenceName();
}
private static boolean isEqualsConstant(PsiExpression expression, PsiVariable variable) {
if (!(expression instanceof PsiMethodCallExpression)) {
return false;
}
final PsiMethodCallExpression methodCallExpression = (PsiMethodCallExpression)expression;
final PsiReferenceExpression methodExpression = methodCallExpression.getMethodExpression();
final String methodName = methodExpression.getReferenceName();
if (!HardcodedMethodConstants.EQUALS.equals(methodName) && !HardcodedMethodConstants.EQUALS_IGNORE_CASE.equals(methodName)) {
return false;
}
final PsiExpression qualifier = methodExpression.getQualifierExpression();
if (!(qualifier instanceof PsiReferenceExpression)) {
return false;
}
final PsiReferenceExpression referenceExpression = (PsiReferenceExpression)qualifier;
final PsiElement target = referenceExpression.resolve();
if (!variable.equals(target)) {
return false;
}
final PsiExpressionList argumentList = methodCallExpression.getArgumentList();
final PsiExpression[] arguments = argumentList.getExpressions();
if (arguments.length != 1) {
return false;
}
final PsiExpression argument = arguments[0];
return PsiUtil.isConstantExpression(argument);
}
}
}