MATLAB Object-Oriented Programming

function cbFunc(obj,varargin)

c = class(obj);

disp(['Java object callback on class ',c])

end

function delete(obj)

c = class(obj);

disp(['ML object destructor called for class ',c])

end

end

end

Suppose that you create a CallbackWithJava object from within a function:

function testDestructor

cwj = CallbackWithJava

...

end

Creating an instance of the CallbackWithJava class creates the

com.mathworks.jmi.Callback object and executes the callback function:

testDestructor

cwj =

CallbackWithJava with no properties.

Java object callback on class CallbackWithJava

The handle variable, cwj, exists only in the function workspace. However, MATLAB does

not call the class delete method when the function ends. The

com.mathworks.jmi.Callback object still exists and holds a reference to the object of

the CallbackWithJava class, which prevents destruction of the MATLAB object.

clear classes

Warning: Objects of 'CallbackWithJava' class exist. Cannot clear this class or

any of its superclasses.

To avoid causing inaccessible objects, call delete explicitly before losing the handle to

the MATLAB object.

function testDestructor

cwj = CallbackWithJava

...

delete(cwj)

end

7 Value or Handle Class — Which to Use