plugins/devkit/src/inspections/quickfix/ImplementOrExtendFix.java

/*
 * Copyright 2000-2009 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 org.jetbrains.idea.devkit.inspections.quickfix;

import com.intellij.codeInspection.LocalQuickFix;
import com.intellij.codeInspection.ProblemDescriptor;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.text.StringUtil;
import com.intellij.pom.Navigatable;
import com.intellij.psi.*;
import com.intellij.util.IncorrectOperationException;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.idea.devkit.DevKitBundle;

/**
 * @author swr
 */
public class ImplementOrExtendFix extends BaseFix {

  private final PsiClass myCompClass;

  private ImplementOrExtendFix(PsiClass compClass, PsiClass checkedClass, boolean onTheFly) {
    super(checkedClass, onTheFly);
    myCompClass = compClass;
  }

  public static LocalQuickFix[] createFix(PsiClass compClass, PsiClass checkedClass, boolean onTheFly) {
    ImplementOrExtendFix fix = null;

    if (compClass.isInterface() && compClass.getImplementsList() != null) {
      fix = new ImplementOrExtendFix(compClass, checkedClass, onTheFly);
    } else if (!compClass.isInterface()) {
      final PsiReferenceList extendsList = checkedClass.getExtendsList();
      if (extendsList != null) {
        if (extendsList.getReferenceElements().length == 0) {
          fix = new ImplementOrExtendFix(compClass, checkedClass, onTheFly);
        } else if (extendsList.getReferenceElements().length == 1) {
          // check for explicit "extends Object" case
          final PsiClassType javaLangObject = PsiType.getJavaLangObject(checkedClass.getManager(),
                  checkedClass.getResolveScope());
          if (extendsList.getReferencedTypes()[0].equals(javaLangObject)) {
            fix = new ImplementOrExtendFix(compClass, checkedClass, onTheFly);
          }
        }
      }
    }
    return fix != null ? new LocalQuickFix[]{fix} : LocalQuickFix.EMPTY_ARRAY;
  }

  @NotNull
  public String getName() {
    return (myCompClass.isInterface()
            ? StringUtil.capitalize(DevKitBundle.message("keyword.implement"))
            : StringUtil.capitalize(DevKitBundle.message("keyword.extend")))
            + " '" + myCompClass.getQualifiedName() + "'";
  }

  @NotNull
  public String getFamilyName() {
    return getName();
  }

  protected void doFix(Project project, ProblemDescriptor descriptor, boolean external) throws IncorrectOperationException {
    final PsiClass clazz = (PsiClass)myElement;
    final PsiElementFactory elementFactory = JavaPsiFacade.getInstance(clazz.getProject()).getElementFactory();
    final PsiClassType compType = elementFactory.createType(myCompClass);

    final PsiReferenceList list;
    if (myCompClass.isInterface()) {
      list = clazz.getImplementsList();
      assert list != null;
    } else {
      final PsiReferenceList extendsList = clazz.getExtendsList();
      assert extendsList != null;
      if (extendsList.getReferencedTypes().length > 0) {
        extendsList.getReferenceElements()[0].delete();
      }
      list = extendsList;
    }

    final PsiElement e = list.add(elementFactory.createReferenceElementByType(compType));
    if (myOnTheFly && external && e instanceof Navigatable) ((Navigatable)e).navigate(true);
  }
}