Toolkit.getDesktopProperty method.
Each desktop property is named by a unique string, which is the "name" of that property.
Desktop properties supported by the AWT but not documented elsewhere - typically because there is no suitable method or class - are documented here.
Desktop properties documented elsewhere are those which are tightly coupled with a method or class which documents them.
Since desktop properties abstract an underlying platform setting, they may not be available in environments that do not support them. In the event that a desktop property is unavailable for any reason, the implementation will return null.
The following table summarizes the desktop properties documented here, and their value types.
| Property Name | Value Type | Summary Description |
|---|---|---|
| awt.font.desktophints | java.util.Map | Font smoothing (text antialiasing) settings. |
| sun.awt.enableExtraMouseButtons | java.lang.Boolean | Controls if mouse events from extra buttons are to be generated or not |
Modern desktops support various forms of text antialiasing (font smoothing).
These are applied by platform-specific heavyweight components. However an application may want to render text using the same text antialiasing on a drawing surface or lightweight (non-platform) component using Graphics2D methods. This is particularly important when creating Swing components which are required to appear consistent with native desktop components or other Swing components.
RenderingHints which can be directly applied to a
Graphics2D.
It is a Map as more than one hint may be needed. If non-null this can be directly applied to the Graphics2D.
Toolkit tk = Toolkit.getDefaultToolkit();
Map map = (Map)(tk.getDesktopProperty("awt.font.desktophints"));
if (map != null) {
graphics2D.addRenderingHints(map);
}
An application can listen for changes in the property using a PropertyChangeListener :
tk.addPropertyChangeListener("awt.font.desktophints", pcl);
There is no direct way to discover if dynamic reconfiguration is expected of running applications but the default assumption should be that it is expected, since most modern desktop environments do provide this capability.
Text always needs to be measured using the same FontRenderContext as used for rendering. The text anti-aliasing hint is a component of the FontRenderContext. A FontMetrics obtained from the Graphics object on which the hint has been set will measure text appropriately. This is not a unique requirement for clients that specify this hint directly, since the value of the FontRenderContext should never be assumed, so is discussed here principally as a reminder.
Sometimes an application may need to apply these hints on a shared Graphics only temporarily, restoring the previous values after they have been applied to text rendering operations. The following sample code shows one way to do this.
/**
* Get rendering hints from a Graphics instance.
* "hintsToSave" is a Map of RenderingHint key-values.
* For each hint key present in that map, the value of that
* hint is obtained from the Graphics and stored as the value
* for the key in savedHints.
*/
RenderingHints getRenderingHints(Graphics2D g2d,
RenderingHints hintsToSave,
RenderingHints savedHints) {
if (savedHints == null) {
savedHints = new RenderingHints(null);
} else {
savedHints.clear();
}
if (hintsToSave.size() == 0) {
return savedHints;
}
/* RenderingHints.keySet() returns Set<Object> */
for (Object o : hintsToSave.keySet()) {
RenderingHints.Key key = (RenderingHints.Key)o;
Object value = g2d.getRenderingHint(key);
savedHints.put(key, value);
}
return savedHints;
}
Toolkit tk = Toolkit.getDefaultToolkit();
Map map = (Map)(tk.getDesktopProperty("awt.font.desktophints"));
Map oldHints;
if (map != null) {
oldHints = getRenderingHints(graphic2D, map, null);
graphics2D.addRenderingHints(map);
..
graphics2D.addRenderingHints(oldHints);
}
Map Map of RenderingHints such that every key is an instance of RenderingHints.Key and the value is a legal value for that key. Graphics2D. If the map did not contain the default value, then addRenderingHints(Map) would leave the previous hint which may not correspond to the desktop setting. An application can use setRenderingHints(Map) to reinitialise all hints, but this would affect unrelated hints too.
"awt.font.desktophints" + "." + GraphicsDevice.getIDstring();
An application can also listen for changes on these properties.
However this is an extremely unlikely configuration, so to help ease of development, if only a single, desktop-wide setting is supported, then querying each of these per-device settings will return null. So to determine if there are per-device settings it is sufficient to determine that there is a non-null return for any screen device using the per-device property name.
This property determines if events from extra mouse buttons (if they are exist and are enabled by the underlying operating system) are allowed to be processed and posted into {@code EventQueue}.
The value could be changed by passing "sun.awt.enableExtraMouseButtons" property value into java before application starts. This could be done with the following command:
java -Dsun.awt.enableExtraMouseButtons=false ApplicationOnce set on application startup, it is impossible to change this value after.