java/java-impl/src/com/intellij/psi/impl/smartPointers/AnchorElementInfoFactory.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.psi.impl.smartPointers;

import com.intellij.psi.*;
import com.intellij.psi.impl.source.PsiFileWithStubSupport;
import com.intellij.psi.stubs.IStubElementType;
import com.intellij.psi.stubs.StubTree;
import com.intellij.psi.util.PsiUtilCore;
import com.intellij.psi.xml.XmlTag;
import com.intellij.xml.util.XmlTagUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

public class AnchorElementInfoFactory implements SmartPointerElementInfoFactory {
  @Override
  @Nullable
  public SmartPointerElementInfo createElementInfo(@NotNull PsiElement element) {
    PsiFile containingFile = element.getContainingFile();
    if (element instanceof StubBasedPsiElement && containingFile instanceof PsiFileWithStubSupport) {
      PsiFileWithStubSupport stubFile = (PsiFileWithStubSupport)containingFile;
      StubTree stubTree = stubFile.getStubTree();
      if (stubTree != null) {
        // use stubs when tree is not loaded
        StubBasedPsiElement stubPsi = (StubBasedPsiElement)element;
        int stubId = PsiAnchor.calcStubIndex(stubPsi);
        IStubElementType myStubElementType = stubPsi.getElementType();
        if (stubId != -1) {
          return new AnchorElementInfo(element, stubFile, stubId, myStubElementType);
        }
      }
    }

    PsiElement anchor = getAnchor(element);
    if (anchor != null) {
      return new AnchorElementInfo(anchor, containingFile);
    }
    return null;
  }

  @Nullable
  static PsiElement getAnchor(PsiElement element) {
    PsiUtilCore.ensureValid(element);
    PsiElement anchor = null;
    if (element instanceof PsiClass) {
      if (element instanceof PsiAnonymousClass) {
        anchor = ((PsiAnonymousClass)element).getBaseClassReference().getReferenceNameElement();
      }
      else {
        anchor = ((PsiClass)element).getNameIdentifier();
      }
    }
    else if (element instanceof PsiMethod) {
      anchor = ((PsiMethod)element).getNameIdentifier();
    }
    else if (element instanceof PsiVariable) {
      anchor = ((PsiVariable)element).getNameIdentifier();
    }
    else if (element instanceof XmlTag) {
      anchor = XmlTagUtil.getStartTagNameElement((XmlTag)element);
    }
    if (anchor != null && (!anchor.isPhysical() /*|| anchor.getTextRange()==null*/)) return null;
    return anchor;
  }
}