/*
* @(#)SynthContext.java 1.9 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package javax.swing.plaf.synth;
import javax.swing.*;
import java.util.*;
/**
* An immutable transient object containing contextual information about
* a Region
. A SynthContext
should only be
* considered valid for the duration
* of the method it is passed to. In other words you should not cache
* a SynthContext
that is passed to you and expect it to
* remain valid.
*
* @version 1.9, 12/19/03
* @since 1.5
* @author Scott Violet
*/
public class SynthContext {
private static final Map contextMap;
private JComponent component;
private Region region;
private SynthStyle style;
private int state;
static {
contextMap = new HashMap();
}
static SynthContext getContext(Class type, JComponent component,
Region region, SynthStyle style,
int state) {
SynthContext context = null;
synchronized(contextMap) {
java.util.List instances = (java.util.List)contextMap.get(type);
if (instances != null) {
int size = instances.size();
if (size > 0) {
context = (SynthContext)instances.remove(size - 1);
}
}
}
if (context == null) {
try {
context = (SynthContext)type.newInstance();
} catch (IllegalAccessException iae) {
} catch (InstantiationException ie) {
}
}
context.reset(component, region, style, state);
return context;
}
static void releaseContext(SynthContext context) {
synchronized(contextMap) {
java.util.List instances = (java.util.List)contextMap.get(
context.getClass());
if (instances == null) {
instances = new ArrayList(5);
contextMap.put(context.getClass(), instances);
}
instances.add(context);
}
}
SynthContext() {
}
/**
* Creates a SynthContext with the specified values. This is meant
* for subclasses and custom UI implementors. You very rarely need to
* construct a SynthContext, though some methods will take one.
*
* @param component JComponent
* @param region Identifies the portion of the JComponent
* @param style Style associated with the component
* @param state State of the component as defined in SynthConstants.
* @throws NullPointerException if component, region of style is null.
*/
public SynthContext(JComponent component, Region region, SynthStyle style,
int state) {
if (component == null || region == null || style == null) {
throw new NullPointerException(
"You must supply a non-null component, region and style");
}
reset(component, region, style, state);
}
/**
* Returns the hosting component containing the region.
*
* @return Hosting Component
*/
public JComponent getComponent() {
return component;
}
/**
* Returns the Region identifying this state.
*
* @return Region of the hosting component
*/
public Region getRegion() {
return region;
}
/**
* A convenience method for getRegion().isSubregion()
.
*/
boolean isSubregion() {
return getRegion().isSubregion();
}
void setStyle(SynthStyle style) {
this.style = style;
}
/**
* Returns the style associated with this Region.
*
* @return SynthStyle associated with the region.
*/
public SynthStyle getStyle() {
return style;
}
void setComponentState(int state) {
this.state = state;
}
/**
* Returns the state of the widget, which is a bitmask of the
* values defined in SynthConstants
. A region will at least
* be in one of
* ENABLED
, MOUSE_OVER
, PRESSED
* or DISABLED
.
*
* @see SynthConstants
* @return State of Component
*/
public int getComponentState() {
return state;
}
/**
* Resets the state of the Context.
*/
void reset(JComponent component, Region region, SynthStyle style,
int state) {
this.component = component;
this.region = region;
this.style = style;
this.state = state;
}
void dispose() {
this.component = null;
this.style = null;
releaseContext(this);
}
/**
* Convenience method to get the Painter from the current SynthStyle.
* This will NEVER return null.
*/
SynthPainter getPainter() {
SynthPainter painter = getStyle().getPainter(this);
if (painter != null) {
return painter;
}
return SynthPainter.NULL_PAINTER;
}
}