ProblematicVarargsMethodOverrideInspection.java

/*
 * Copyright 2000-2016 JetBrains s.r.o.
 *
 * 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.inheritance;

import com.intellij.psi.*;
import com.siyeh.InspectionGadgetsBundle;
import com.siyeh.ig.BaseInspection;
import com.siyeh.ig.BaseInspectionVisitor;
import com.siyeh.ig.InspectionGadgetsFix;
import com.siyeh.ig.fixes.ConvertToVarargsMethodFix;
import org.jetbrains.annotations.Nls;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author Bas Leijdekkers
 */
public class ProblematicVarargsMethodOverrideInspection extends BaseInspection {

  @Nls
  @NotNull
  @Override
  public String getDisplayName() {
    return InspectionGadgetsBundle.message("problematic.varargs.method.display.name");
  }

  @NotNull
  @Override
  protected String buildErrorString(Object... infos) {
    return InspectionGadgetsBundle.message("problematic.varargs.method.override.problem.descriptor");
  }

  @Nullable
  @Override
  protected InspectionGadgetsFix buildFix(Object... infos) {
    return new ConvertToVarargsMethodFix();
  }

  @Override
  public BaseInspectionVisitor buildVisitor() {
    return new NonVarargsMethodOverridesVarArgsMethodVisitor();
  }

  private static class NonVarargsMethodOverridesVarArgsMethodVisitor extends BaseInspectionVisitor {

    @Override
    public void visitMethod(PsiMethod method) {
      super.visitMethod(method);
      final PsiParameterList parameterList = method.getParameterList();
      final PsiParameter[] parameters = parameterList.getParameters();
      if (parameters.length == 0) {
        return;
      }
      final PsiParameter parameter = parameters[parameters.length - 1];
      final PsiType type = parameter.getType();
      if (!(type instanceof PsiArrayType) || type instanceof PsiEllipsisType) {
        return;
      }
      final PsiMethod[] superMethods = method.findDeepestSuperMethods();
      for (final PsiMethod superMethod : superMethods) {
        if (superMethod.isVarArgs()) {
          final PsiElement nameIdentifier = method.getNameIdentifier();
          if (nameIdentifier != null) {
            registerErrorAtOffset(method, nameIdentifier.getStartOffsetInParent(), nameIdentifier.getTextLength());
          }
          return;
        }
      }
    }
  }
}