6 Accessibility Properties

The javax.accessibility package provides the following properties: assistive_technologies and screen_magnifier_present.

Loading Assistive Technologies

The assistive_technologies property specifies the assistive technologies to load into the JVM. It takes a comma-delimited list of service provider names. See the javax.accessibility package, the javax.accessibility.AccessibilityProvider abstract class, and the java.awt.Toolkit.getDefaultToolkit method.

Indicating the Presence of a Screen Magnifier

When the screen_magnifier_present property is set to true, it lets the Java platform libraries know that a screen magnifier is present on the system. Application developers can check this property, and if a screen magnifier is present, developers should make sure their applications are compatible with screen magnification. For example, on Microsoft Windows operating systems, the reference implementation of the Java 2D API checks this property and if true, turns off Microsoft DirectDraw to avoid problems with the screen magnifier. (Some screen magnifiers may not be able to magnify DirectDraw graphics.)

Setting Properties

Set a property at run time with the following command:

java -Djavax.accessibility.assistive_technologies=ServiceProviderName

ServiceProvicerName is the name of a service provider that adds an assistive technology feature; see the javax.accessibility.AccessibilityProvider.getName method.

You can also specify properties in a file named .accessibility.properties in the user's home directory or a file named accessibility.properties in the $JAVA_HOME/conf directory. In the former case, the properties are used for the current user, and in the latter case, the properties are used for all users of that Java installation. The properties set for the current user take precedence over the properties set for the Java installation.

Set a property in the accessibility.properties file by adding line or lines as follows:



You can specify more than one service provider in the assistive_technologies property with a comma-delimited list.