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Determine if Java feature is available


tf = usejava(feature)



tf = usejava(feature) returns logical 1 (true) if the specified feature is supported. Otherwise, it returns logical 0 (false). If the Java® feature is unavailable, then you can use this function for error handling.


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Use the following code snippet to test that the AWT GUI components are available before attempting to display a Java Frame. If the AWT is not available on your system, MATLAB® displays the message Unable to open a Java Frame.

if usejava('awt')
   myFrame = java.awt.Frame;
   disp('Unable to open a Java Frame')

Use the following code snippet to terminate a script if MATLAB does not have access to JVM™ software.

The variable, filename, is a function that contains Java code.

if ~usejava('jvm')
   error([filename ' requires Java to run.'])

Input Arguments

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Java feature, specified as one of these values.


UI components in the Java Abstract Window Toolkit (AWT) are available.


MATLAB interactive desktop is running.


Java Virtual Machine software (JVM) is running.


Swing components (Java lightweight UI components in the Java Foundation Classes) are available.

Introduced before R2006a