com.antelmann.net
Class Downloader

java.lang.Object
  com.antelmann.net.Downloader

All Implemented Interfaces:

Runnable

public class Downloader
extends Object
implements Runnable

Downloads a URL or URLCache object into a file. You can either download the URL synchronously using the provided static method or asynchronously in a separate thread. When doing the latter, you can first instanciate this Runnable, register a listener (in case you want to be notified upon completion) and then start the thread. If in a separate thread, you can also monitor the progress of the download using getReadSoFar() or cancel the download.

Author:

Holger Antelmann

See Also:

JDownloader

Nested Class Summary

static interface

Downloader.Listener

Field Summary

static int	LENGTH_NOT_OBTAINED_YET
static int	THREAD_NOT_STARTED_YET
static int	UNKNOWN_LENGTH

Constructor Summary

Downloader(URLCache uc, File file)

Downloader(URLCache uc, OutputStream out)
closes the stream on completion

Downloader(URLCache uc, OutputStream out, boolean closeOnCompletion)

Downloader(URLCache uc, OutputStream out, boolean closeOnCompletion, Monitor monitor)

Downloader(URL url, File file)

Downloader(URL url, OutputStream out)
closes the stream on completion

Method Summary

void	addListener(Downloader.Listener listener)
void	cancel() cancels the current download; the listeners will be called with an IOException containing the message that canced() was called or that the input stream was closed
static void	download(URLCache uc, File file) synchronously downloads the given uc to the given file
static void	download(URLCache uc, OutputStream out) synchronously downloads the given url to the given output stream
static void	download(URLCache uc, OutputStream out, String user, char[] password) synchronously downloads the given url to the given output stream using basic authorization mechanism
static void	download(URL url, File file) synchronously downloads the given url to the given file
static void	download(URL url, OutputStream out) synchronously downloads the given url to the given output stream
int	getBufferSize()
boolean	getCloseOnCompletion()
int	getContentLength() returns the content length or LENGTH_NOT_OBTAINED_YET if the download hasn't been started, yet; UNKNOWN_LENGTH is returned if the length is unknown
OutputStream	getOutputStream()
int	getReadSoFar() returns the bytes that have been read by the thread; returns THREAD_NOT_STARTED_YET if the thread hasn't been started, yet
URL	getURL()
void	run() downloads the URL to the file and calls any listeners upon completion
void	setBasicAuthorization(String user, char[] password) if the user is non-null, the InputStream will be obtained via basic authorization
void	setBufferSize(int size)
void	setCloseOnCompletion(boolean flag)
void	setMonitor(Monitor monitor)

Methods inherited from class java.lang.Object

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

Field Detail

UNKNOWN_LENGTH

public static final int UNKNOWN_LENGTH

See Also:

Constant Field Values

LENGTH_NOT_OBTAINED_YET

public static final int LENGTH_NOT_OBTAINED_YET

See Also:

Constant Field Values

THREAD_NOT_STARTED_YET

public static final int THREAD_NOT_STARTED_YET

See Also:

Constant Field Values

Constructor Detail

Downloader

public Downloader(URL url,
                  File file)
           throws FileNotFoundException

Throws:

FileNotFoundException

Downloader

public Downloader(URLCache uc,
                  File file)
           throws FileNotFoundException

Throws:

FileNotFoundException

Downloader

public Downloader(URL url,
                  OutputStream out)

closes the stream on completion

Downloader

public Downloader(URLCache uc,
                  OutputStream out)

closes the stream on completion

Downloader

public Downloader(URLCache uc,
                  OutputStream out,
                  boolean closeOnCompletion)

Downloader

public Downloader(URLCache uc,
                  OutputStream out,
                  boolean closeOnCompletion,
                  Monitor monitor)

Method Detail

setMonitor

public void setMonitor(Monitor monitor)

setBasicAuthorization

public void setBasicAuthorization(String user,
                                  char[] password)

if the user is non-null, the InputStream will be obtained via basic authorization

setCloseOnCompletion

public void setCloseOnCompletion(boolean flag)
                          throws IllegalStateException

Throws:

IllegalStateException

getCloseOnCompletion

public boolean getCloseOnCompletion()

download

public static void download(URL url,
                            File file)
                     throws IOException

synchronously downloads the given url to the given file

Throws:

IOException

download

public static void download(URLCache uc,
                            File file)
                     throws IOException

synchronously downloads the given uc to the given file

Throws:

IOException

download

public static void download(URL url,
                            OutputStream out)
                     throws IOException

synchronously downloads the given url to the given output stream

Throws:

IOException

download

public static void download(URLCache uc,
                            OutputStream out)
                     throws IOException

synchronously downloads the given url to the given output stream

Throws:

IOException

download

public static void download(URLCache uc,
                            OutputStream out,
                            String user,
                            char[] password)
                     throws IOException

synchronously downloads the given url to the given output stream using basic authorization mechanism

Throws:

IOException

cancel

public void cancel()

cancels the current download; the listeners will be called with an IOException containing the message that canced() was called or that the input stream was closed

setBufferSize

public void setBufferSize(int size)
                   throws IllegalStateException

Throws:

IllegalStateException

getBufferSize

public int getBufferSize()

run

public void run()

downloads the URL to the file and calls any listeners upon completion

Specified by:

run in interface Runnable

See Also:

Downloader.Listener, addListener(Downloader.Listener)

getOutputStream

public OutputStream getOutputStream()

getURL

public URL getURL()

getReadSoFar

public int getReadSoFar()

returns the bytes that have been read by the thread; returns THREAD_NOT_STARTED_YET if the thread hasn't been started, yet

getContentLength

public int getContentLength()

returns the content length or LENGTH_NOT_OBTAINED_YET if the download hasn't been started, yet; UNKNOWN_LENGTH is returned if the length is unknown

addListener

public void addListener(Downloader.Listener listener)