Test for valid graphics or Java object handle
Note: You should use the most specific function for your application instead of ishandle, as described in the following sections.
Use the isa function to determine the class of MATLAB® objects and use the isvalid handle class method to determine the validity of handle objects. See Testing Handle Validity for information on testing for MATLAB handle objects.
Use ishghandle for graphics objects.
Use isjava for Java objects.