| /* |
| * Copyright 2007-2010 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.siyeh.InspectionGadgetsBundle; |
| import com.siyeh.ig.BaseInspection; |
| import com.siyeh.ig.BaseInspectionVisitor; |
| import com.siyeh.ig.psiutils.MethodUtils; |
| import org.jetbrains.annotations.Nls; |
| import org.jetbrains.annotations.NotNull; |
| |
| import java.util.*; |
| |
| public class ComparatorMethodParameterNotUsedInspection |
| extends BaseInspection { |
| |
| @Override |
| @Nls |
| @NotNull |
| public String getDisplayName() { |
| return InspectionGadgetsBundle.message( |
| "comparator.method.parameter.not.used.display.name"); |
| } |
| |
| @Override |
| @NotNull |
| protected String buildErrorString(Object... infos) { |
| return InspectionGadgetsBundle.message( |
| "comparator.method.parameter.not.used.problem.descriptor"); |
| } |
| |
| @Override |
| public boolean isEnabledByDefault() { |
| return true; |
| } |
| |
| @Override |
| public BaseInspectionVisitor buildVisitor() { |
| return new CompareMethodDoesNotUseParameterVisitor(); |
| } |
| |
| private static class CompareMethodDoesNotUseParameterVisitor |
| extends BaseInspectionVisitor { |
| |
| @Override |
| public void visitMethod(PsiMethod method) { |
| super.visitMethod(method); |
| if (!MethodUtils.methodMatches(method, |
| CommonClassNames.JAVA_UTIL_COMPARATOR, |
| PsiType.INT, "compare", PsiType.NULL, PsiType.NULL)) { |
| return; |
| } |
| final PsiCodeBlock body = method.getBody(); |
| if (body == null) { |
| return; |
| } |
| final PsiParameterList parameterList = method.getParameterList(); |
| final PsiParameter[] parameters = parameterList.getParameters(); |
| final ParameterAccessVisitor visitor = |
| new ParameterAccessVisitor(parameters); |
| body.accept(visitor); |
| final Collection<PsiParameter> unusedParameters = |
| visitor.getUnusedParameters(); |
| for (PsiParameter unusedParameter : unusedParameters) { |
| registerVariableError(unusedParameter); |
| } |
| } |
| |
| private static class ParameterAccessVisitor |
| extends JavaRecursiveElementVisitor { |
| |
| private final Set<PsiParameter> parameters; |
| |
| ParameterAccessVisitor(@NotNull PsiParameter[] parameters) { |
| this.parameters = new HashSet(Arrays.asList(parameters)); |
| } |
| |
| @Override |
| public void visitReferenceExpression( |
| PsiReferenceExpression expression) { |
| super.visitReferenceExpression(expression); |
| if (parameters.isEmpty()) { |
| return; |
| } |
| if (expression.getQualifierExpression() != null) { |
| // optimization |
| // references to parameters are never qualified |
| return; |
| } |
| final PsiElement target = expression.resolve(); |
| if (!(target instanceof PsiParameter)) { |
| return; |
| } |
| final PsiParameter parameter = (PsiParameter)target; |
| parameters.remove(parameter); |
| } |
| |
| public Collection<PsiParameter> getUnusedParameters() { |
| return Collections.unmodifiableSet(parameters); |
| } |
| } |
| } |
| } |