MATLAB: How to check if a string is the name of a custom subclass

inheritanceMATLABmcossubsuperunittest

I have a cell array of strings with names of files that match certain criteria. Now want to test if each of these strings is 1) the name of a class and 2) if it is a class, is it a subclass of the MATLAB Unit Test class. How can I do this?

Best Answer

You can use a combination of the "exist", "ismember", and "superclasses" functions. This lets you see if a given string represents a class name and whether that class is a subclass of the MATLAB Unit Test superclass. The general syntax is as follows:

exist("classname", 'class') && ismember("superclassName", superclasses("classname"))

In this both "classname" and "superclassName" are strings. This will return logical 1 if "classname" is both a class and "superclassName" appears in the set of its superclasses. This can handle many levels of inheritance, since the "superclasses" function does not only include direct superclasses.

Related Solutions

MATLAB: How to call the set-dot method on a subclass object to set a property of the superclass

You cannot define a "set.xyz" method in a subclass to set the "xyz" property of the superclass. This restriction prevents a subclass from overriding a superclass implementation and cannot be bypassed. However, in some situations superclass property needs to grant subclasses the ability to participate in the setting or getting of a property value, like in this case. To do so, a superclass "set" function can call a protected method to allow subclasses to participate in property access while still maintaining some level of control.

So the implementation of the two classes might look like this:

classdef MySuperClass < handle
      properties
          xyz
      end
      methods
        function set.xyz(obj,value)
           disp(['setting xyz in MySuperClass to ', value]);
           obj.xyz = value; % updates the property
           respondToXYZChange(obj) % calls the protected method
        end 
     end 
     methods(Access = protected)
        function respondToXYZChange(obj, value) % no function definition here
        end
     end
end 
classdef MySubClass < MySuperClass
      methods
          function obj=MySubClass()
              disp('!');
          end
          function update(obj)
              disp('updating...');
          end
      end
      methods(Access = protected)
          function respondToXYZChange(obj) % call to the "update" method of subclass
              obj.update();
          end
      end
end
>> m  = MySubClass3;
!
>> m.xyz = 'a'
setting xyz in MySuperClass to a
updating...
m = 
    MySubClass3 with properties:
      xyz: 'a'
>>

Executing the command:

m.xyz = 'a';

calls the superclass "set" method which sets the value of the property "xyz" and then calls the protected "respondToXYZChange" which is defined in the subclass to call the "update" method.

MATLAB: How to list only those methods defined or overloaded in a certain classdef file

As per commented, this can be done through meta objects,

    function nameCell=methodslocal(classname)
    %Return the names of non-Hidden methods defined 
    %or overloaded in the class called 'classname'
    %
    %    nameCell=methodslocal(classname)
      mcls = meta.class.fromName(classname);
      ml=mcls.MethodList;
        ml=ml(~[ml.Hidden]);
      N=numel(ml);
      for i=N:-1:1, 
          c{i}=ml(i).DefiningClass.Name; 
      end
      lidx = strcmp(c,classname);
      nameCell=sortrows({ml(lidx).Name}.').';

Best Answer

Related Solutions

MATLAB: How to call the set-dot method on a subclass object to set a property of the superclass

MATLAB: How to list only those methods defined or overloaded in a certain classdef file

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