How MATLAB Handles Undefined Methods :: Calling Java from MATLAB (External Interfaces)

External Interfaces

How MATLAB Handles Undefined Methods

If your MATLAB command invokes a nonexistent method on a Java object, MATLAB looks for a built-in function with the same name. If MATLAB finds a built-in function of that name, it attempts to invoke it. If MATLAB does not find a function with that name, it displays a message stating that it cannot find a method by that name for the class.

For example, MATLAB has a built-in method named size, and the Java API java.awt.Frame class also has a size method. If you call size on a Frame object, the size method defined by java.awt.Frame is executed. However, if you call size on an object of java.lang.String, MATLAB does not find a size method for this class. It executes the MATLAB size built-in instead.

string = java.lang.String('hello'); 

size(string)
ans =
     1     1

Note When you define a Java class for use in MATLAB, avoid giving any of its methods the same name as a MATLAB built-in function.

How MATLAB Handles Java Exceptions

If invoking a Java method or constructor throws an exception, MATLAB catches the exception and transforms it into a MATLAB error. MATLAB puts the text of the Java error message into its own error message. Receiving an error from a Java method or constructor has the same appearance as receiving an error from an M-file.

Java Methods That Affect MATLAB Commands Working with Java Arrays