archive.java

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   * Get an attribute from the manifest of the archive.
   *
   * @param key Name of attribute to get.
   * @return A string with result or null if the entry doesn't exists.
   */
  String getAttribute(String key) {
    Attributes a = manifest.getMainAttributes();
    if (a != null) {
      return a.getValue(key);
    }
    return null;
  }
  

  /**
   * Get all attributes from the manifest of the archive.
   *
   * @return All attributes.
   */
  Attributes getAttributes() {
    return manifest.getMainAttributes();
  }
  

  /**
   * Get a byte array containg the contents of named file from
   * the archive.
   *
   * @param component File to get.
   * @return Byte array with contents of file or null if file doesn't exist.
   * @exception IOException if failed to read jar entry.
   */
  byte[] getBytes(String component) throws IOException {
    if(bClosed) {
      return null;
    }

    ZipEntry ze;
    InputStream is;
    int len;
    if (jar != null) {
      if (subJar != null) {
	JarInputStream ji = new JarInputStream(jar.getInputStream(subJar));
	do {
	  ze = ji.getNextJarEntry();
	  if (ze == null) {
	    ji.close();
	    return null;
	  }
	} while (!component.equals(ze.getName()));
	is = (InputStream)ji;
      } else {
	ze = jar.getEntry(component);
	if (ze == null) {
	  return null;
	}
	is = jar.getInputStream(ze);
      }
      len = (int)ze.getSize();
    } else {
      File f = findFile(file, component);
      if (f.exists()) {
	is = new FileInputStream(f);
	len = is.available();
      } else {
	return null;
      }
    }
    byte[] bytes;
    if (len >= 0) {
      bytes = new byte[len];
      DataInputStream dis = new DataInputStream(is);
      dis.readFully(bytes);
    } else {
      bytes = new byte[0];
      byte[] tmp = new byte[8192];
      try {
	while ((len = is.read(tmp)) > 0) {
	  byte[] oldbytes = bytes;
	  bytes = new byte[oldbytes.length + len];
	  System.arraycopy(oldbytes, 0, bytes, 0, oldbytes.length);
	  System.arraycopy(tmp, 0, bytes, oldbytes.length, len);
	}
      } catch (EOFException ignore) {
	// On Pjava we somtimes get a mysterious EOF excpetion,
	// but everything seems okey. (SUN Bug 4040920)
      }
    }
    is.close();
    return bytes;
  }


  /**
   * Get an InputStream to named entry inside an Archive.
   *
   * @param component Entry to get reference to.
   * @return InputStream to entry or null if it doesn't exist.
   */
  InputStream getInputStream(String component) {
    if(bClosed) {
      return null;
    }
    if (component.startsWith("/")) {
      component = component.substring(1);
    }
    ZipEntry ze;
    InputStream is;
    try {
      if (jar != null) {
	if (subJar != null) {
	  JarInputStream ji = new JarInputStream(jar.getInputStream(subJar));
	  do {
	    ze = ji.getNextJarEntry();
	    if (ze == null) {
	      ji.close();
	      return null;
	    }
	  } while (!component.equals(ze.getName()));
	  is = (InputStream)ji;
	} else {
	  ze = jar.getEntry(component);
	  is = (ze != null) ? jar.getInputStream(ze) : null;
	}
      } else {
	File f = findFile(file, component);
	is = f.exists() ? new FileInputStream(f) : null;
      }
      return is;
    } catch (IOException ignore) {
      return null;
    }
  }


  /**
   * Get an Archive handle to a named Jar file within this archive.
   *
   * @param path Name of Jar file to get.
   * @return An Archive object representing new archive.
   * @exception FileNotFoundException if no such Jar file in archive.
   * @exception IOException if failed to read Jar file.
   */
  Archive getSubArchive(String path) throws IOException {
    if(bClosed) {
      return null;
    }
    return new Archive(this, path);
  }


  /**
   * Extract native library from JAR.
   *
   * @param key Name of Jar file to get.
   * @return A string with path to native library.
   */
  String getNativeLibrary(String path) throws IOException {
    if(bClosed) {
      throw new IOException("Archive is closed");
    }
    File lib;
    if (jar != null) {
      lib = getSubFile(this, path);
      if (!lib.exists()) {
	(new File(lib.getParent())).mkdirs();
	ZipEntry ze = jar.getEntry(path);
	if (ze != null) {
	  InputStream is = jar.getInputStream(ze);
	  try {
	    loadFile(lib, is, false);
	  } finally {
	    is.close();
	  }
	} else {
	  throw new FileNotFoundException("No such sub-archive: " + path);
	}
      }
    } else {
      lib = findFile(file, path);
//XXX - start L-3 modification
      if (!lib.exists() && (lib.getParent() != null)) {
	final String libname = lib.getName();
	File[] list = lib.getParentFile().listFiles(new FilenameFilter() {
	  public boolean accept(File dir, String name) {
	    int pos = name.lastIndexOf(libname);
	    return ((pos > 1) && (name.charAt(pos - 1) == '_'));
	  }
	});
	if (list.length > 0) {
	  lib = list[0];
	}
      }
//XXX - end L-3 modification
    }
    return lib.getAbsolutePath();
  }


  /**
   * Remove archive and any unpacked sub-archives.
   */
  void purge() {
    close();
    // Remove archive
    file.delete();
    // Remove any cached sub files
    getSubFileTree(this).delete();
  }

  boolean bClosed = false;

  /**
   * Close archive and all open sub-archives.
   * If close fails it is silently ignored.
   */
  void close() {
    bClosed = true; // Mark as closed to safely handle referenced files
    if (subJar == null && jar != null) {
      try {
	jar.close();
      } catch (IOException ignore) {}
    }
  }

  //
  // Private methods
  //

  /**
   * Check that we have a valid manifest for the bundle
   * and if we need to unpack bundle for fast performance,
   * i.e has native code file or subjars.
   *
   * @return true if bundle needs to be unpack.
   * @exception IllegalArgumentException if we have a broken manifest.
   */
  private boolean checkManifest() {
    Attributes a = manifest.getMainAttributes();
    Util.parseEntries(Constants.EXPORT_PACKAGE, a.getValue(Constants.EXPORT_PACKAGE), true);
    Util.parseEntries(Constants.IMPORT_PACKAGE, a.getValue(Constants.IMPORT_PACKAGE), true);
    Iterator nc = Util.parseEntries(Constants.BUNDLE_NATIVECODE, a.getValue(Constants.BUNDLE_NATIVECODE), false);
    String bc = a.getValue(Constants.BUNDLE_CLASSPATH);
    return (bc != null && !bc.trim().equals(".")) || nc.hasNext();
  }


  /**
   * Get file handle for file inside a directory structure.
   * The path for the file is always specified with a '/'
   * separated path.
   *
   * @param root Directory structure to search.
   * @param path Path to file to find.
   * @return The File object for file <code>path</code>.
   */
  private File findFile(File root, String path) {
    return new File(root, path.replace('/', File.separatorChar));
  }

  /**
   * Get the manifest for this archive.
   *
   * @return The manifest for this Archive
   */
  private Manifest getManifest() throws IOException {
    // TBD: Should recognize entry with lower case?
    InputStream is = getInputStream("META-INF/MANIFEST.MF");
    if (is != null) {
      return new Manifest(is);
    } else {
      throw new IOException("Manifest is missing");
    }
  }


  /**
   * Get dir for unpacked components.
   *
   * @param archive Archive which contains the components.
   * @return FileTree for archives component cache directory.
   */
  private FileTree getSubFileTree(Archive archive) {
    return new FileTree(archive.file.getParent(),
			SUBDIR + archive.file.getName().substring(ARCHIVE.length()));
  }


  /**
   * Get file for an unpacked component.
   *
   * @param archive Archive which contains the component.
   * @param path Name of the component to get.
   * @return File for componets cache file.
   */
  private File getSubFile(Archive archive, String path) {
    return new File(getSubFileTree(archive), path.replace('/', '-'));
  }


  /**
   * Loads a file from an InputStream and stores it in a file.
   *
   * @param output File to save data in.
   * @param is InputStream to read from.
   */
  private void loadFile(File output, InputStream is, boolean verify) throws IOException {
    OutputStream os = null;
    // NYI! Verify
    try {
      os = new FileOutputStream(output);
      byte[] buf = new byte[8192];
      int n;
      try {
	while ((n = is.read(buf)) > 0) {
	  os.write(buf, 0, n);
	}
      } catch (EOFException ignore) {
	// On Pjava we somtimes get a mysterious EOF excpetion,
	// but everything seems okey. (SUN Bug 4040920)
      }
    } catch (IOException e) {
      output.delete();
      throw e;
    } finally {
      if (os != null) {
	os.close();
      }
    }
  }

}