JavaMethodHierarchyProvider.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 com.intellij.ide.hierarchy.method;

import com.intellij.ide.hierarchy.HierarchyBrowser;
import com.intellij.ide.hierarchy.HierarchyProvider;
import com.intellij.ide.hierarchy.MethodHierarchyBrowserBase;
import com.intellij.openapi.actionSystem.CommonDataKeys;
import com.intellij.openapi.actionSystem.DataContext;
import com.intellij.openapi.editor.Editor;
import com.intellij.openapi.project.Project;
import com.intellij.psi.*;
import com.intellij.psi.util.PsiTreeUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author yole
 */
public class JavaMethodHierarchyProvider implements HierarchyProvider {
  public PsiElement getTarget(@NotNull final DataContext dataContext) {
    final PsiMethod method = getMethodImpl(dataContext);
    if (
      method != null &&
      method.getContainingClass() != null &&
      !method.hasModifierProperty(PsiModifier.PRIVATE) &&
      !method.hasModifierProperty(PsiModifier.STATIC)
    ){
      return method;
    }
    else {
      return null;
    }
  }

  @Nullable
  private static PsiMethod getMethodImpl(final DataContext dataContext){
    final Project project = CommonDataKeys.PROJECT.getData(dataContext);
    if (project == null) return null;

    PsiElement element = CommonDataKeys.PSI_ELEMENT.getData(dataContext);
    final PsiMethod method = PsiTreeUtil.getParentOfType(element, PsiMethod.class, false);

    if (method != null) {
      return method;
    }

    final Editor editor = CommonDataKeys.EDITOR.getData(dataContext);
    if (editor == null) {
      return null;
    }

    final PsiFile psiFile = PsiDocumentManager.getInstance(project).getPsiFile(editor.getDocument());
    if (psiFile == null) {
      return null;
    }

    final int offset = editor.getCaretModel().getOffset();
    if (offset < 1) {
      return null;
    }

    element = psiFile.findElementAt(offset);
    if (!(element instanceof PsiWhiteSpace)) {
      return null;
    }

    element = psiFile.findElementAt(offset - 1);
    if (!(element instanceof PsiJavaToken) || ((PsiJavaToken)element).getTokenType() != JavaTokenType.SEMICOLON) {
      return null;
    }

    return PsiTreeUtil.getParentOfType(element, PsiMethod.class, false);
  }

  @NotNull
  public HierarchyBrowser createHierarchyBrowser(final PsiElement target) {
    return new MethodHierarchyBrowser(target.getProject(), (PsiMethod) target);
  }

  public void browserActivated(@NotNull final HierarchyBrowser hierarchyBrowser) {
    ((MethodHierarchyBrowser) hierarchyBrowser).changeView(MethodHierarchyBrowserBase.METHOD_TYPE);
  }
}