file.java

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	/**
	  * This method creates a directory for the path represented by this object.
	  *
	  * @return <code>true</code> if the directory was created, <code>false</code> otherwise
	  *
	  * @exception SecurityException If write access is not allowed to this file
	  */
	public boolean mkdir() throws SecurityException {
		// Check the SecurityManager
		SecurityManager sm = System.getSecurityManager();
		if (sm != null)
			sm.checkWrite(path);

		String mk_path;
		mk_path = PlatformHelper.removeTailSeparator(path);
        
		return (mkdirInternal(mk_path));
	}

	/*************************************************************************/

	/**
	  * This native method actually creates the directory
	  */
	private boolean mkdirInternal(String path) {
		
      String absolute = PlatformHelper.toCanonicalForm(getAbsolutePath());
        
      // TODO
        
        
      return false;
	}

	/*************************************************************************/

	/**
	  * This method creates a directory for the path represented by this file.
	  * It will also create any intervening parent directories if necessary.
	  *
	  * @return <code>true</code> if the directory was created, <code>false</code> otherwise
	  *
	  * @exception SecurityException If write access is not allowed to this file
	  */
	public boolean mkdirs() throws SecurityException {
		String parent = getParent();
		if (parent == null) {
			return (mkdir());
		}

		File f = new File(parent);
		if (!f.exists()) {
			boolean rc = f.mkdirs();
			if (rc == false)
				return (false);
		}

		return (mkdir());
	}

	/*************************************************************************/

	/**
	  * This method renames the file represented by this object to the path
	  * of the file represented by the argument <code>File</code>.
	  *
	  * @param dest The <code>File</code> object representing the target name
	  *
	  * @return <code>true</code> if the rename succeeds, <code>false</code> otherwise.
	  *
	  * @exception SecurityException If write access is not allowed to the file by the <code>SecurityMananger</code>.
	  */
	public synchronized boolean renameTo(File dest) throws SecurityException {
		// Check the SecurityManager
		SecurityManager sm = System.getSecurityManager();
		if (sm != null)
			sm.checkWrite(path);

		// Call our native rename method
		boolean rc = renameToInternal(path, dest.getPath());

		return (rc);
	}

	/*************************************************************************/

	/**
	  * This native method actually performs the rename.
	  */
	private boolean renameToInternal(String target, String dest) {
		return false;
	}

	/*************************************************************************/

	/**
	  * This method returns a array of <code>String</code>'s representing the
	  * list of files is then directory represented by this object.  If this
	  * object represents a non-directory file or a non-existent file, then
	  * <code>null</code> is returned.  The list of files will not contain
	  * any names such as "." or ".." which indicate the current or parent
	  * directory.  Also, the names are not guaranteed to be sorted.
	  * <p>
	  * A <code>SecurityManager</code> check is made prior to reading the
	  * directory.  If read access to the directory is denied, an exception
	  * will be thrown.
	  *
	  * @return An array of files in the directory, or <code>null</code> if this object does not represent a valid directory.
	  * 
	  * @exception SecurityException If read access is not allowed to the directory by the <code>SecurityManager</code>
	  */
	public String[] list() {
		return (list(null));
	}

	/*************************************************************************/

	/**
	  * This method returns a array of <code>String</code>'s representing the
	  * list of files is then directory represented by this object.  If this
	  * object represents a non-directory file or a non-existent file, then
	  * <code>null</code> is returned.  The list of files will not contain
	  * any names such as "." or ".." which indicate the current or parent
	  * directory.  Also, the names are not guaranteed to be sorted.
	  * <p>
	  * In this form of the <code>list()</code> method, a filter is specified
	  * that allows the caller to control which files are returned in the
	  * list.  The <code>FilenameFilter</code> specified is called for each
	  * file returned to determine whether or not that file should be included
	  * in the list.
	  * <p>
	  * A <code>SecurityManager</code> check is made prior to reading the
	  * directory.  If read access to the directory is denied, an exception
	  * will be thrown.
	  *
	  * @param filter An object which will identify files to exclude from the directory listing.
	  *
	  * @return An array of files in the directory, or <code>null</code> if this object does not represent a valid directory.
	  * 
	  * @exception SecurityException If read access is not allowed to the directory by the <code>SecurityManager</code>
	  */
	public String[] list(FilenameFilter filter) {
		// Check the SecurityManager
		final SecurityManager sm = System.getSecurityManager();
		if (sm != null) {
			sm.checkRead(path);
		}

		// Get the list of files
		final String list_path = PlatformHelper.removeTailSeparator(path);
		final File dir = new File(list_path);

		if (!dir.exists() || !dir.isDirectory()) {
			return null;
		}

		try {
			final String files[] = VMIOUtils.getAPI().list(dir, filter);
			if (files == null) {
				return new String[0];
			} else {
				return files;
			}

		} catch (IOException ex) {
			return null;
		}

	}

	/*************************************************************************/

	/**
	  * This method returns an array of <code>File</code> objects representing
	  * all the files in the directory represented by this object. If this
	  * object does not represent a directory, <code>null</code> is returned.
	  * Each of the returned <code>File</code> object is constructed with this
	  * object as its parent.
	  * <p>
	  * A <code>SecurityManager</code> check is made prior to reading the
	  * directory.  If read access to the directory is denied, an exception
	  * will be thrown.
	  *
	  * @return An array of <code>File</code> objects for this directory.
	  *
	  * @exception SecurityException If the <code>SecurityManager</code> denies
	  * access to this directory.
	  */
	public File[] listFiles() {
		return listFiles((FilenameFilter)null);
	}

	/*************************************************************************/

	/**
	  * This method returns an array of <code>File</code> objects representing
	  * all the files in the directory represented by this object. If this
	  * object does not represent a directory, <code>null</code> is returned.
	  * Each of the returned <code>File</code> object is constructed with this
	  * object as its parent.
	  * <p> 
	  * In this form of the <code>listFiles()</code> method, a filter is specified
	  * that allows the caller to control which files are returned in the
	  * list.  The <code>FilenameFilter</code> specified is called for each
	  * file returned to determine whether or not that file should be included
	  * in the list.
	  * <p>
	  * A <code>SecurityManager</code> check is made prior to reading the
	  * directory.  If read access to the directory is denied, an exception
	  * will be thrown.
	  *
	  * @return An array of <code>File</code> objects for this directory.
	  *
	  * @exception SecurityException If the <code>SecurityManager</code> denies
	  * access to this directory.
	  */
	public File[] listFiles(FilenameFilter filter) {
		String[] filelist = list(filter);
		if (filelist == null) {
			return (null);
		}

		File[] fobjlist = new File[filelist.length];

		for (int i = 0; i < filelist.length; i++) {
			fobjlist[i] = new File(this, filelist[i]);
		}

		return (fobjlist);
	}

	/*************************************************************************/

	/**
	  * This method returns an array of <code>File</code> objects representing
	  * all the files in the directory represented by this object. If this
	  * object does not represent a directory, <code>null</code> is returned.
	  * Each of the returned <code>File</code> object is constructed with this
	  * object as its parent.
	  * <p> 
	  * In this form of the <code>listFiles()</code> method, a filter is specified
	  * that allows the caller to control which files are returned in the
	  * list.  The <code>FileFilter</code> specified is called for each
	  * file returned to determine whether or not that file should be included
	  * in the list.
	  * <p>
	  * A <code>SecurityManager</code> check is made prior to reading the
	  * directory.  If read access to the directory is denied, an exception
	  * will be thrown.
	  *
	  * @return An array of <code>File</code> objects for this directory.
	  *
	  * @exception SecurityException If the <code>SecurityManager</code> denies
	  * access to this directory.
	  */
	public File[] listFiles(FileFilter filter) {
		File[] fobjlist = listFiles((FilenameFilter) null);

		if (fobjlist == null)
			return (null);

		if (filter == null)
			return (fobjlist);

		int count = 0;
		for (int i = 0; i < fobjlist.length; i++)
			if (filter.accept(fobjlist[i]) == true)
				++count;

		File[] final_list = new File[count];
		count = 0;
		for (int i = 0; i < fobjlist.length; i++)
			if (filter.accept(fobjlist[i]) == true) {
				final_list[count] = fobjlist[i];
				++count;
			}

		return (final_list);
	}

	/*************************************************************************/

	/**
	  * This method compares the specified <code>Object</code> to this one
	  * to test for equality.  It does this by comparing the canonical path names
	  * of the files.  This method is identical to <code>compareTo(File)</code>
	  * except that if the <code>Object</code> passed to it is not a 
	  * <code>File</code>, it throws a <code>ClassCastException</code>
	  * <p>
	  * The canonical paths of the files are determined by calling the
	  * <code>getCanonicalPath</code> method on each object.
	  * <p>
	  * This method returns a 0 if the specified <code>Object</code> is equal
	  * to this one, a negative value if it is less than this one 
	  * a positive value if it is greater than this one.
	  *
	  * @return An integer as described above
	  *
	  * @exception ClassCastException If the passed <code>Object</code> is not a <code>File</code>
	  */
	public int compareTo(Object obj) throws ClassCastException {
		return (compareTo((File)obj));
	}

	/*************************************************************************/

	/**
	  * This method compares the specified <code>File</code> to this one
	  * to test for equality.  It does this by comparing the canonical path names
	  * of the files. 
	  * <p>
	  * The canonical paths of the files are determined by calling the
	  * <code>getCanonicalPath</code> method on each object.
	  * <p>
	  * This method returns a 0 if the specified <code>Object</code> is equal
	  * to this one, a negative value if it is less than this one 
	  * a positive value if it is greater than this one.
	  *
	  * @return An integer as described above
	  */
	public int compareTo(File file) {
		String p1, p2;
		try {
			p1 = getCanonicalPath();
			p2 = file.getCanonicalPath();
		} catch (IOException e) {
			// What do we do here?  The spec requires the canonical path.  Even
			// if we don't call the method, we must replicate the functionality
			// which per the spec can fail.  What happens in that situation?
			// I just assume the files are equal!
			//
			return (0);
		}

		return (p1.compareTo(p2));
	}

	/*************************************************************************/

	/**
	  * This method tests two <code>File</code> objects for equality by 
	  * comparing the path of the specified <code>File</code> against the path
	  * of this object.  The two objects are equal if an only if 1) The
	  * argument is not null 2) The argument is a <code>File</code> object and
	  * 3) The path of the <code>File</code>argument is equal to the path
	  * of this object.
	  * <p>
	  * The paths of the files are determined by calling the <code>getPath()</code>
	  * method on each object.
	  *
	  * @return <code>true</code> if the two objects are equal, <code>false</code> otherwise.
	  */
	public boolean equals(Object obj) {
		if (obj == null)
			return (false);

		if (!(obj instanceof File))
			return (false);

		File f = (File)obj;

		return (f.getPath().equals(getPath()));
	}

	/*************************************************************************/

	/**
	  * This method returns a hash code representing this file.  It is the
	  * hash code of the path of this file (as returned by <code>getPath()</code>)
	  * exclusived or-ed with the value 1234321.
	  *
	  * @return The hash code for this object
	  */
	public int hashCode() {
		return (getPath().hashCode() ^ 1234321);
	}

	/*************************************************************************/

	/**
	  * This method returns a <code>String</code> that is the path name of the
	  * file as returned by <code>getPath</code>.
	  *
	  * @return A <code>String</code> representation of this file
	  */
	public String toString() {
		return (path);
	}

	/*************************************************************************/

	/**
	  * This method returns a <code>URL</code> with the <code>file:</code>
	  * protocol that represents this file.  The exact form of this URL is
	  * system dependent.
	  *
	  * @return A <code>URL</code> for this object.
	  *
	  * @exception MalformedURLException If the URL cannot be created successfully.
	  */
	public URL toURL() throws MalformedURLException {
		String abspath = getAbsolutePath();
		try {
			if (new File(abspath).isDirectory())
				abspath = abspath + separator;
		} catch (Exception _) {
		}

		String url_string = "file://" + abspath;

		return (new URL(url_string));
	}

} // class File