org.vrspace.util
Class NetResource

java.lang.Object
  org.vrspace.util.NetResource

public class NetResource

extends java.lang.Object

This class represents a network resource - a collection of URLs pointing to same file.

Field Summary

java.util.Vector

urls

Constructor Summary

NetResource()

NetResource(java.lang.String urlSpec)
This constructor creates NetResource with specified urls.

Method Summary

void	addURL(java.lang.String urlSpec) Adds url to the list.
java.net.URL	getURL() Returns prefered URL of this resource.
static void	main(java.lang.String[] args)
java.lang.String[]	toArray() Returns urls as string array
java.lang.String	toSpecString() Returns string in format [ url1,url2,...urlN ]
java.lang.String	toString() Returns url list delimited by space
void	update() Updates this resource info.

Methods inherited from class java.lang.Object

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

Field Detail

urls

public java.util.Vector urls

Constructor Detail

NetResource

public NetResource()

NetResource

public NetResource(java.lang.String urlSpec)

This constructor creates NetResource with specified urls.

Parameters:

urlSpec - url list delimited by space

Method Detail

toString

public java.lang.String toString()

Returns url list delimited by space

toArray

public java.lang.String[] toArray()

Returns urls as string array

toSpecString

public java.lang.String toSpecString()

Returns string in format [ url1,url2,...urlN ]

getURL

public java.net.URL getURL()

Returns prefered URL of this resource. Checks whether URL is available by opening a connection.

Returns:

URL or null if there is no available URLs for this resource

addURL

public void addURL(java.lang.String urlSpec)
            throws java.io.IOException

Adds url to the list. Checks whether URL is accessible.

Throws:

java.net.MalformedURLException - if unsupported protocol is specified

java.io.IOException - if URL content is unacessible

update

public void update()

Updates this resource info. Opens connections to each url in list and checks for availability. Ensures that all urls are available.

main

public static void main(java.lang.String[] args)
                 throws java.lang.Exception

Throws:

java.lang.Exception