AbstractChangeTracker (OpenJPA Parent POM 3.1.0 API)

java.lang.Object
- org.apache.openjpa.util.AbstractChangeTracker

All Implemented Interfaces:

ChangeTracker

Direct Known Subclasses:

CollectionChangeTrackerImpl, MapChangeTrackerImpl
```
public abstract class AbstractChangeTracker
extends Object
implements ChangeTracker
```
Base class that provides utilities to change trackers.

Author:

Abe White

Field Summary

Fields
Modifier and Type	Field and Description
`protected Collection`	`add` Collection of added items.
`protected Collection`	`change` Collection of changed items.
`protected Collection`	`rem` Collection of removed items.

Constructor Summary

Constructors
Constructor and Description

AbstractChangeTracker()
Constructor; supply configuration.

Constructors
Constructor and Description
`AbstractChangeTracker()` Constructor; supply configuration.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`protected abstract void`	`add(Object val)` Mark the given value as added.
`protected void`	`added(Object val)` Notify the tracker that the given object was added.
`protected abstract void`	`change(Object val)` Mark the given value as changed.
`protected void`	`changed(Object val)` Notify the tracker that the given object was changed.
`Collection`	`getAdded()` Return the collection of values that need to be added to the managed container.
`boolean`	`getAutoOff()` Whether to automatically stop tracking when the number of changes exceeds the container size.
`Collection`	`getChanged()` Return the set of elements that have changed.
`int`	`getNextSequence()` The next element sequence value for this proxy at load time.
`Collection`	`getRemoved()` Return the set of values that need to be removed from the managed container.
`protected int`	`initialSequence()` Return the initial sequence value for this proxy.
`boolean`	`isTracking()` Return true if this tracker has an up-to-date view of all the changes to the container it is managing.
`protected Set`	`newSet()` Create a new set for storing adds/removes/changes.
`protected abstract void`	`remove(Object val)` Mark the given value as removed.
`protected void`	`removed(Object val)` Notify the tracker that the given object was removed.
`protected void`	`reset()` Reset the state of the tracker.
`void`	`setAutoOff(boolean autoOff)` Whether to automatically stop tracking when the number of changes exceeds the container size.
`void`	`setNextSequence(int seq)` The maximum element sequence value for this proxy at load time.
`void`	`startTracking()` Reset the state of the change tracker, and turn change tracking back on if it has been disabled.
`void`	`stopTracking()` Tell the tracker to stop tracking changes for its container.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - add
```
protected Collection add
```
    Collection of added items. May be null.
  - rem
```
protected Collection rem
```
    Collection of removed items. May be null.
  - change
```
protected Collection change
```
    Collection of changed items. May be null.
- Constructor Detail
  - AbstractChangeTracker
```
public AbstractChangeTracker()
```
    Constructor; supply configuration.
- Method Detail
  - getAutoOff
```
public boolean getAutoOff()
```
    Whether to automatically stop tracking when the number of changes exceeds the container size. Defaults to true.
  - setAutoOff
```
public void setAutoOff(boolean autoOff)
```
    Whether to automatically stop tracking when the number of changes exceeds the container size. Defaults to true.
  - isTracking
```
public boolean isTracking()
```
    Description copied from interface: ChangeTracker
    
    Return true if this tracker has an up-to-date view of all the changes to the container it is managing.
    
    Specified by:
    
    isTracking in interface ChangeTracker
  - startTracking
```
public void startTracking()
```
    Description copied from interface: ChangeTracker
    
    Reset the state of the change tracker, and turn change tracking back on if it has been disabled.
    
    Specified by:
    
    startTracking in interface ChangeTracker
  - initialSequence
```
protected int initialSequence()
```
    Return the initial sequence value for this proxy. Typically this is the container size. Assumes an unordered collection by default, returning 0.
  - stopTracking
```
public void stopTracking()
```
    Description copied from interface: ChangeTracker
    
    Tell the tracker to stop tracking changes for its container.
    
    Specified by:
    
    stopTracking in interface ChangeTracker
  - reset
```
protected void reset()
```
    Reset the state of the tracker.
  - getAdded
```
public Collection getAdded()
```
    Description copied from interface: ChangeTracker
    
    Return the collection of values that need to be added to the managed container.
    
    Specified by:
    
    getAdded in interface ChangeTracker
  - getRemoved
```
public Collection getRemoved()
```
    Description copied from interface: ChangeTracker
    
    Return the set of values that need to be removed from the managed container.
    
    Specified by:
    
    getRemoved in interface ChangeTracker
  - getChanged
```
public Collection getChanged()
```
    Description copied from interface: ChangeTracker
    
    Return the set of elements that have changed. In maps, this marks a possible change in value for a key. In collections, this marks an element that has been removed and re-added.
    
    Specified by:
    
    getChanged in interface ChangeTracker
  - added
```
protected void added(Object val)
```
    Notify the tracker that the given object was added.
  - add
```
protected abstract void add(Object val)
```
    Mark the given value as added.
  - removed
```
protected void removed(Object val)
```
    Notify the tracker that the given object was removed.
  - remove
```
protected abstract void remove(Object val)
```
    Mark the given value as removed.
  - changed
```
protected void changed(Object val)
```
    Notify the tracker that the given object was changed.
  - change
```
protected abstract void change(Object val)
```
    Mark the given value as changed.
  - getNextSequence
```
public int getNextSequence()
```
    Description copied from interface: ChangeTracker
    
    The next element sequence value for this proxy at load time. If the data store keeps this proxy's data in sequence order but allows holes for removed objects, the implementation can set the next sequence at load time, then retrieve it and start from there for added objects at flush time. This value is set back to 0 if the proxy stops tracking changes. For ordered proxies, it is set to the proxy's size when the proxy starts tracking changes again.
    
    Specified by:
    
    getNextSequence in interface ChangeTracker
  - setNextSequence
```
public void setNextSequence(int seq)
```
    Description copied from interface: ChangeTracker
    
    The maximum element sequence value for this proxy at load time. If the data store keeps this proxy's data in sequence order but allows holes for removed objects, the implementation can set the next sequence at load time, then retrieve it and start from there for added objects at flush time. This value is set back to 0 if the proxy stops tracking changes. For ordered proxies, it is set to the proxy's size when the proxy starts tracking changes again.
    
    Specified by:
    
    setNextSequence in interface ChangeTracker
  - newSet
```
protected Set newSet()
```
    Create a new set for storing adds/removes/changes. Takes into account whether we need to use an identity set or standard set.

Class AbstractChangeTracker

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

add

rem

change

Constructor Detail

AbstractChangeTracker

Method Detail

getAutoOff

setAutoOff

isTracking

startTracking

initialSequence

stopTracking

reset

getAdded

getRemoved

getChanged

added

add

removed

remove

changed

change

getNextSequence

setNextSequence

newSet