cbr.service
Class PictureDB

java.lang.Object
  de.fhg.igd.semoa.service.AbstractService
      cbr.service.PictureDB

All Implemented Interfaces:

PicsSource, Service

public class PictureDB

extends AbstractService

implements PicsSource

A class which implements the service that is used to advertise the pictures.

This class provides an iterator for the pictures in the configured picture directory. This iterator attempts to open and read line by line a file with the name " ls.txt" in the picture directory. This file must contain the names of the known pictures. Such a file can be created simply by issuing the command ls >ls.txt in the picture directory.

Iterating through the picture names and loading pictures requires that this class has privileges to read said files and that the reading instance is created by a class that has said privileges also. Malicious code can not create an instance of this class and exploit it to access said directories. See AbstractService for details.

Be careful, this class contains a security hole that might allow untrusted code to delete files!

Version:

"$Id: PictureDB.java 1913 2007-08-08 02:41:53Z jpeters $"

Author:

Volker Roth

See Also:

PrivilegedOpen, Service

Field Summary

protected File	pictures_ The directory from which pictures are loaded.
protected File	thumbnails_ The directory from which thumbnails are loaded.

Fields inherited from class de.fhg.igd.semoa.service.AbstractService

REV_POSTFIX, REV_PREFIX

Constructor Summary

PictureDB()
Creates an instance.

PictureDB(File p, File t)
Creates an instance which loads images from the given directories.

Method Summary

String	author() Returns the name of the author of the service.
byte[]	getPicture(String name) Retrieves a picture based on the name.
byte[]	getThumbnail(String name) Retrieves a thumbnail based on the name.
String	info() Returns the informative string which should describe the service's essence in a sentence.
Iterator	iterator() Returns an iterator that iterates the names of the available pictures.
private byte[]	loadPicture(File file) Loads a file into a byte array.
String	revision() Returns the revision number of this class as a string.
void	setPictures(File file)
void	setThumbnails(File file)

Methods inherited from class de.fhg.igd.semoa.service.AbstractService

checkDependencies, dependencies, docs, doPrivileged, doPrivileged, getACC, getEnvironment, majorVersion, minorVersion, toString

Methods inherited from class java.lang.Object

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

Field Detail

pictures_

protected File pictures_

The directory from which pictures are loaded.

thumbnails_

protected File thumbnails_

The directory from which thumbnails are loaded.

Constructor Detail

PictureDB

public PictureDB()

Creates an instance.

PictureDB

public PictureDB(File p,
                 File t)

Creates an instance which loads images from the given directories. For each image there should be a thumbnail available. Thumbnails must have the same name as the picture to which they refer.

Parameters:

p - The directory containing the available pictures.

t - The directory containing the thumbnails for the available pictures.

Method Detail

author

public String author()

Description copied from class: AbstractService

Returns the name of the author of the service. The format to be used should be John Doe <jdoe@zilch.net>.

Specified by:

author in interface Service

Specified by:

author in class AbstractService

Returns:

the String with the author's name.

revision

public String revision()

Description copied from class: AbstractService

Returns the revision number of this class as a string. This class provides default implementations of methods majorVersion(), minorVersion based on the assumption that this method returns a revision string as generated by rcs(1) for the template "$Revision: 1.7 $/$Date: 2007-08-08 04:41:53 +0200 (Wed, 08 Aug 2007) $".

Specified by:

revision in class AbstractService

info

public String info()

Description copied from class: AbstractService

Returns the informative string which should describe the service's essence in a sentence.

Specified by:

info in interface Service

Specified by:

info in class AbstractService

Returns:

the String with the service's short description.

setPictures

public void setPictures(File file)

setThumbnails

public void setThumbnails(File file)

iterator

public Iterator iterator()

Returns an iterator that iterates the names of the available pictures.

Specified by:

iterator in interface PicsSource

Returns:

The iterator that iterates the names of the available pictures..

getPicture

public byte[] getPicture(String name)

Retrieves a picture based on the name.

Specified by:

getPicture in interface PicsSource

Parameters:

name - The name of the picture. This name must be locally unique.

Returns:

The encoding of the picture with the given name.

getThumbnail

public byte[] getThumbnail(String name)

Retrieves a thumbnail based on the name.

Specified by:

getThumbnail in interface PicsSource

Parameters:

name - The name of the picture. This name must be locally unique.

Returns:

The encoding of the picture with the given name.

loadPicture

private byte[] loadPicture(File file)

Loads a file into a byte array. This method is used for loading pictures and thumbnails from folders to which access is restricted.

Parameters:

file - The file to load.

Returns:

The bytes of the file.