net.named_data.jndn.util

Class ChangeCounter

java.lang.Object

net.named_data.jndn.util.ChangeCounter

public class ChangeCounter
extends Object

A ChangeCounter keeps a pointer to a target ChangeCountable whose change count is tracked by a local change count. You can set to a new target which updates the local change count, and you can call checkChanged to check if the target (or one of the target's targets) has been changed.

Constructor Summary

Constructors

Constructor and Description
ChangeCounter(ChangeCountable target) Create a new ChangeCounter to track the given target.

Method Summary

Modifier and Type	Method and Description
boolean	checkChanged() If the target's change count is different than the local change count, then update the local change count and return true.
ChangeCountable	get() Get the target object.
void	set(ChangeCountable target) Set the target to the given target.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChangeCounter

public ChangeCounter(ChangeCountable target)

Create a new ChangeCounter to track the given target. If target is not null, this sets the local change counter to target.getChangeCount().

Parameters:

target - The target to track. This may be null.

Method Detail

get

public final ChangeCountable get()

Get the target object. If the target is changed, then checkChanged will detect it.

Returns:

The target object.

set

public final void set(ChangeCountable target)

Set the target to the given target. If target is not null, this sets the local change counter to target.getChangeCount().

Parameters:

target - The target to track. This may be null.

checkChanged

public final boolean checkChanged()

If the target's change count is different than the local change count, then update the local change count and return true. Otherwise return false, meaning that the target has not changed. Also, if the target is null, simply return false.This is useful since the target (or one of the target's targets) may be changed and you need to find out.

Returns:

True if the change count has been updated, false if not.