Files.java

/*
 * Copyright 2003-2016 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 jetbrains.mps.vfs;

import jetbrains.mps.vfs.path.Path;
import org.jetbrains.annotations.NotNull;

import java.io.File;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.StringJoiner;

/**
 * Shorthand for {@link IFile} management.
 *
 * @author apyshkin
 */
public final class Files {
  private Files() {}

  @NotNull
  public static IFile getFile(@NotNull String mainPart, @NotNull String... parts) {
    StringJoiner joiner = new StringJoiner(Path.UNIX_SEPARATOR);
    joiner.add(mainPart);
    for (String part : parts) {
      joiner.add(part);
    }
    return FileSystemExtPoint.getFS().getFile(joiner.toString());
  }

  /**
   * Usually when one calls URL#getPath he expects the result to be without scheme.
   * However in the case of the 'jar' scheme it is not true (nicely done, JDK!)
   * Hence the hack to resolve 'jar:file://a.jar!/a.txt' like URI is to resolve two times.
   *
   * see <code>jetbrains.mps.workbench.index.RootNodeNameIndex</code> for a long and boring explanation
   *
   * fixme it is better to parse on our own [apyshkin]
   */
  @NotNull
  public static IFile fromURL(@NotNull URL url) {
    try {
      String path = url.getPath();
      if (!path.startsWith("/")) { //strangely not absolute
        if ("jar".equals(url.getProtocol())) {
          if (path.startsWith("file:")) {
            URL hackUrl = new URL(path);
            String authority = hackUrl.getAuthority();
            path = (authority != null ? authority : "") + hackUrl.getPath();
          }
          return getFile(path);
        }
      }
      return getFile(path);
    } catch (MalformedURLException e) {
      throw new RuntimeException(e);
    }
  }
}