platform/core-impl/src/com/intellij/psi/impl/smartPointers/FileElementInfo.java

/*
 * Copyright 2000-2010 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.lang.Language;
import com.intellij.openapi.editor.Document;
import com.intellij.openapi.editor.RangeMarker;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.util.Comparing;
import com.intellij.openapi.util.Segment;
import com.intellij.openapi.util.TextRange;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import org.jetbrains.annotations.NotNull;

/**
* User: cdr
*/
class FileElementInfo implements SmartPointerElementInfo {
  protected final VirtualFile myVirtualFile;
  protected final Project myProject;
  protected final Language myLanguage;

  public FileElementInfo(@NotNull PsiFile file) {
    this(file.getProject(), file.getVirtualFile(), file.getLanguage());
  }
  protected FileElementInfo(@NotNull Project project, VirtualFile virtualFile) {
    this(project, virtualFile, null);
  }

  protected FileElementInfo(@NotNull Project project, VirtualFile virtualFile, Language lang) {
    myVirtualFile = virtualFile;
    myProject = project;
    myLanguage = lang;
  }

  @Override
  public Document getDocumentToSynchronize() {
    return null;
  }

  @Override
  public void fastenBelt(int offset, RangeMarker[] cachedRangeMarker) {
  }

  @Override
  public void unfastenBelt(int offset) {
  }

  @Override
  public PsiElement restoreElement() {
    return SelfElementInfo.restoreFileFromVirtual(myVirtualFile, myProject, myLanguage);
  }

  @Override
  public PsiFile restoreFile() {
    PsiElement element = restoreElement();
    return element == null ? null : element.getContainingFile(); // can be directory
  }

  @Override
  public int elementHashCode() {
    return myVirtualFile.hashCode();
  }

  @Override
  public boolean pointsToTheSameElementAs(@NotNull SmartPointerElementInfo other) {
    if (other instanceof FileElementInfo) {
      return Comparing.equal(myVirtualFile, ((FileElementInfo)other).myVirtualFile);
    }
    if (other instanceof SelfElementInfo || other instanceof ClsElementInfo) {
      // optimisation: SelfElementInfo need psi (parsing) for element restoration and apriori could not reference psi file
      return false;
    }
    return Comparing.equal(restoreElement(), other.restoreElement());
  }

  @Override
  public VirtualFile getVirtualFile() {
    return myVirtualFile;
  }

  @Override
  public Segment getRange() {
    return new TextRange(0, (int)myVirtualFile.getLength());
  }

  @NotNull
  @Override
  public Project getProject() {
    return myProject;
  }

  @Override
  public void cleanup() {

  }
}