platform/core-api/src/com/intellij/openapi/vfs/StandardFileSystems.java

/*
 * Copyright 2000-2012 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.openapi.vfs;

import com.intellij.ide.highlighter.ArchiveFileType;
import com.intellij.openapi.util.NotNullLazyValue;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author yole
 */
public class StandardFileSystems {
  public static String FILE_PROTOCOL = "file";
  public static String FILE_PROTOCOL_PREFIX = "file://";
  public static String JAR_PROTOCOL = "jar";
  public static String JAR_PROTOCOL_PREFIX = "jar://";
  public static String JAR_SEPARATOR = "!/";
  public static String HTTP_PROTOCOL = "http";

  private static final NotNullLazyValue<VirtualFileSystem> ourLocal = new NotNullLazyValue<VirtualFileSystem>() {
    @NotNull
    @Override
    protected VirtualFileSystem compute() {
      return VirtualFileManager.getInstance().getFileSystem(FILE_PROTOCOL);
    }
  };

  private static final NotNullLazyValue<VirtualFileSystem> ourJar = new NotNullLazyValue<VirtualFileSystem>() {
    @NotNull
    @Override
    protected VirtualFileSystem compute() {
      return VirtualFileManager.getInstance().getFileSystem(JAR_PROTOCOL);
    }
  };

  public static VirtualFileSystem local() {
    return ourLocal.getValue();
  }

  public static VirtualFileSystem jar() {
    return ourJar.getValue();
  }

  @Nullable
  public static VirtualFile getJarRootForLocalFile(@NotNull VirtualFile virtualFile) {
    if (virtualFile.getFileType() != ArchiveFileType.INSTANCE) return null;

    final String path = virtualFile.getPath() + JAR_SEPARATOR;
    return jar().findFileByPath(path);
  }

  @Nullable
  public static VirtualFile getVirtualFileForJar(@Nullable VirtualFile entryVFile) {
    if (entryVFile == null) return null;
    final String path = entryVFile.getPath();
    final int separatorIndex = path.indexOf(JAR_SEPARATOR);
    if (separatorIndex < 0) return null;

    String localPath = path.substring(0, separatorIndex);
    return local().findFileByPath(localPath);
  }
}