Question

I am trying to invoke the API with the given input parameters. Input params are coming as a List. Now my job is get the API’s parameter types one by one and build the required type instance from List. I am able to do for simple java types , List, Set but I am stuck at the array.

Method  method = getMethodFromTheClassBasedOnvalues(  loadedClass,   apiName, numberOfParams);
     Type[] apiMethodParams = method.getGenericParameterTypes();
         List<Type> expectedParamTypes = Arrays.asList(apiMethodArgTypes);
     List<Object> actualValues = // method input.

    List<Object> argsList = new ArrayList<Object>();
    for (int i = 0; i < expectedParamTypes.length; i++) {
        argsList.add(castToRequiredType(expectedParamTypes.get(i),
                actualValues.get(i)));

    method.invoke(loadClass.newInstance(), argsList.toArray());

The problem comes when I get the method which is of type API (String, String[]) I try to get GenericTypes by calling method.getGenericParameterTypes() which returns and array something like this :
[class java.lang.String, class [Ljava.lang.String;] or if one parameter [Ljava.lang.String;
Based on this how would I know if its taking Array of String. I see difference is class name is starting after [L and finishes with; but is it guaranteed?
Will the bevhiour be same for CustomObject[] also?

Is there any smart way to know if the method is taking an array and to build it lately?
Any thoughts in this direction will help.

Thanks in advance.

Answer 1

Try to use

Class[] Mehotd.getParameterTypes()

After that you can call Class.isArray() and determine does this parameter class is array