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Generics and Reflection

What is an upper bound?

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There is a class TestClass that has a method returning upper bounded wildcard type. But we don't know a parameter type of the return value:

class TestClass {
    ...
    public Set<? extends UNKNOWN_TYPE> someMethod() {
        //
    }
    ..
}

To obtain it, let's implement printParameterType method that accepts an instance of TestClass and the name of its method.

The method should print a full name of the return upper bound type (package + class name).

Sample Input 1:

stringMethod

Sample Output 1:

java.lang.String

Write a program in Java 17

// Do not remove imports

import java.lang.reflect.Field;

import java.lang.reflect.Method;

import java.lang.reflect.ParameterizedType;

import java.lang.reflect.WildcardType;

import java.util.Set;

import java.util.Scanner;

class ListParameterInspector {

// Do not change the method

public static void main(String[] args) throws Exception {

Scanner scanner = new Scanner(System.in);

String methodName = scanner.next();

ListParameterInspector inspector = new ListParameterInspector();

inspector.printParameterType(new TestClass(), methodName);

}

public void printParameterType(TestClass obj, String methodName) throws Exception {

// Add implementation here

}

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