javax.swing.text

Class AsyncBoxView.ChildState

java.lang.Object

javax.swing.text.AsyncBoxView.ChildState

All Implemented Interfaces:

Runnable

Enclosing class:

AsyncBoxView

public class AsyncBoxView.ChildState
extends Object
implements Runnable

A record representing the layout state of a child view. It is runnable as a task on another thread. All access to the child view that is based upon a read-lock on the model should synchronize on this object (i.e. The layout thread and the GUI thread can both have a read lock on the model at the same time and are not protected from each other). Access to a child view hierarchy is serialized via synchronization on the ChildState instance.

Since:

1.3

Constructor Summary

Constructors

Constructor and Description
AsyncBoxView.ChildState(View v) Construct a child status.

Method Summary

Methods

Modifier and Type	Method and Description
View	getChildView() Fetch the child view this record represents
float	getMajorOffset() Get the offset along the major axis
float	getMajorSpan() What is the span along the major axis.
float	getMinorOffset() What is the offset along the minor axis
float	getMinorSpan() What is the span along the minor axis.
boolean	isLayoutValid() Has the child view been laid out.
void	preferenceChanged(boolean width, boolean height) Mark preferences changed for this child.
void	run() Update the child state.
void	setMajorOffset(float offs) This method should only be called by the ChildLocator, it is simply a convenient place to hold the cached location.

Methods inherited from class java.lang.Object

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

Constructor Detail

AsyncBoxView.ChildState

public AsyncBoxView.ChildState(View v)

Construct a child status. This needs to start out as fairly large so we don't falsely begin with the idea that all of the children are visible.

Since:

1.4

Method Detail

getChildView

public View getChildView()

Fetch the child view this record represents

run

public void run()

Update the child state. This should be called by the thread that desires to spend time updating the child state (intended to be the layout thread).

This aquires a read lock on the associated document for the duration of the update to ensure the model is not changed while it is operating. The first thing to do would be to see if any work actually needs to be done. The following could have conceivably happened while the state was waiting to be updated:

1. The child may have been removed from the view hierarchy.
2. The child may have been updated by a higher priority operation (i.e. the child may have become visible).

Specified by:

run in interface Runnable

See Also:

Thread.run()