eap.tar
Class Unpacker

java.lang.Object
  java.awt.Component
      java.awt.Container
          java.awt.Panel
              java.applet.Applet
                  javax.swing.JApplet
                      eap.tar.Unpacker

All Implemented Interfaces:

Accessible, ActionListener, EventListener, ImageObserver, MenuContainer, RootPaneContainer, Runnable, Serializable

public class Unpacker

extends JApplet

implements Runnable, ActionListener

An applet for downloading and unpacking a tar file. Not only will it unpack a tar, but it will also filter files using the eap.filter package. This currently means that it can decrypt PGP files and uncompress gzipped files. The filtering can be applied to the individual entries in the tar as well as to the tar itself (e.g. a .tgz file). Other formats besides tar could be supported with some additional code, and additional filters can be added.

This applet uses the following parameters:

• SOURCE - A URL from which to read the tar file. The URL may be relative to the HTML page containing the applet.
• PASSWORD - The key used to decrypt the tar and or the files in it. This is useful if the key is stored in a cookie.
• DATASET - A unique keyword identifying this dataset. The applet uses this keyword to store an encryption key after it prompts for one. If you do not include this parameter, then the applet will prompt for the key each time it encounters an encrypted file in the tar. Note that the password it remembered across HTML pages, so be sure to make the key unique unless two tars use the same encryption key.

Note that this applet writes data to the user's local machine, so this applet needs to be signed so that the user can grant it permission to do that.

See Also:

Serialized Form

Nested Class Summary

Nested classes inherited from class javax.swing.JApplet

JApplet.AccessibleJApplet

Nested classes inherited from class java.applet.Applet

Applet.AccessibleApplet

Nested classes inherited from class java.awt.Panel

Panel.AccessibleAWTPanel

Nested classes inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes inherited from class java.awt.Component

Component.AccessibleAWTComponent, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields inherited from class javax.swing.JApplet

accessibleContext, rootPane, rootPaneCheckingEnabled

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Unpacker()
Create a new applet.

Method Summary

void	actionPerformed(ActionEvent e) Responds to the "Download" button
void	init() This method is called after the browser loads the applet.
void	message(String message) Reports a message to the user.
void	open(String source) Create an Archive corresponding to the given source.
void	run() Implements the Runnable interface.
void	unpack(File top) Unpack the archive

Methods inherited from class javax.swing.JApplet

addImpl, createRootPane, getAccessibleContext, getContentPane, getGlassPane, getJMenuBar, getLayeredPane, getRootPane, isRootPaneCheckingEnabled, paramString, remove, setContentPane, setGlassPane, setJMenuBar, setLayeredPane, setLayout, setRootPane, setRootPaneCheckingEnabled, update

Methods inherited from class java.applet.Applet

destroy, getAppletContext, getAppletInfo, getAudioClip, getAudioClip, getCodeBase, getDocumentBase, getImage, getImage, getLocale, getParameter, getParameterInfo, isActive, newAudioClip, play, play, resize, resize, setStub, showStatus, start, stop

Methods inherited from class java.awt.Panel

addNotify

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getInsets, getLayout, getListeners, getMaximumSize, getMinimumSize, getPreferredSize, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paint, paintComponents, preferredSize, print, printComponents, processContainerEvent, processEvent, remove, removeAll, removeContainerListener, removeNotify, setFocusCycleRoot, setFocusTraversalKeys, setFocusTraversalPolicy, setFont, transferFocusBackward, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isOpaque, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, reshape, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Unpacker

public Unpacker()

Create a new applet. This sets up the filters.

Method Detail

init

public void init()

This method is called after the browser loads the applet.

message

public void message(String message)

Reports a message to the user.

open

public void open(String source)
          throws IOException

Create an Archive corresponding to the given source. Currently only tar format data are supported, but the intent is to one day recognize other formats.

Parameters:

source - A string representation of the URL for the tar file. This can be relative to the page containing the applet.

Throws:

IOException

actionPerformed

public void actionPerformed(ActionEvent e)

Responds to the "Download" button

Specified by:

actionPerformed in interface ActionListener

unpack

public void unpack(File top)
            throws IOException

Unpack the archive

Parameters:

top - The directory on the user's local machine into which the data will be written.

Throws:

IOException

run

public void run()

Implements the Runnable interface. This method is called to do what the applet does in a separate thread.

Specified by:

run in interface Runnable