com.openharbor.beck.map
Class PollableResource

java.lang.Object
  com.openharbor.beck.map.PollableResource

All Implemented Interfaces:

PollableInput

public class PollableResource

extends java.lang.Object

implements PollableInput

A resource with a relatively efficient method to check whether it has changed. This class is not thread-safe.

Field Summary

protected java.lang.ClassLoader	loader
protected org.apache.commons.logging.Log	log
protected java.lang.String	resourceName

Fields inherited from interface com.openharbor.beck.map.PollableInput

SECONDS

Constructor Summary

PollableResource(java.lang.ClassLoader loader, java.lang.String name)

Method Summary

protected java.net.URL	getResource()
java.lang.String	getSystemID() The SystemID that identifies the input source, or null if its SystemID is unknown.
java.io.InputStream	input() Begin reading the data (as a stream of bytes).
java.io.InputStream	inputIfModified() Begin reading the data (as a stream of bytes) if it has changed since the last call to input() or inputIfModified().
protected PollableURL	newPollableURL(java.net.URL url)
void	pollSoon() Check for a change in the data next time inputIfModified is called, regardless of the currently acceptable staleness.
void	setAcceptableStaleness(long msec) Set the maximum amount of time that may elapse from a change in the data until the change is detected by this object.

Methods inherited from class java.lang.Object

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

Field Detail

log

protected final org.apache.commons.logging.Log log

loader

protected java.lang.ClassLoader loader

resourceName

protected java.lang.String resourceName

Constructor Detail

PollableResource

public PollableResource(java.lang.ClassLoader loader,
                        java.lang.String name)

Method Detail

setAcceptableStaleness

public void setAcceptableStaleness(long msec)

Description copied from interface: PollableInput

Set the maximum amount of time that may elapse from a change in the data until the change is detected by this object.

Specified by:

setAcceptableStaleness in interface PollableInput

Parameters:

msec - the acceptable staleness, in units of milliseconds.

getSystemID

public java.lang.String getSystemID()

Description copied from interface: PollableInput

The SystemID that identifies the input source, or null if its SystemID is unknown.

Specified by:

getSystemID in interface PollableInput

input

public java.io.InputStream input()
                          throws java.io.IOException

Description copied from interface: PollableInput

Begin reading the data (as a stream of bytes).

Specified by:

input in interface PollableInput

Throws:

java.io.IOException

inputIfModified

public java.io.InputStream inputIfModified()
                                    throws java.io.IOException

Description copied from interface: PollableInput

Begin reading the data (as a stream of bytes) if it has changed since the last call to input() or inputIfModified().

Specified by:

inputIfModified in interface PollableInput

Returns:

a stream that will produce the data, or null to indicate that the data have not changed.

Throws:

java.io.IOException

pollSoon

public void pollSoon()

Description copied from interface: PollableInput

Check for a change in the data next time inputIfModified is called, regardless of the currently acceptable staleness.

Specified by:

pollSoon in interface PollableInput

getResource

protected java.net.URL getResource()
                            throws java.io.FileNotFoundException

Throws:

java.io.FileNotFoundException

newPollableURL

protected PollableURL newPollableURL(java.net.URL url)