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Generics and Reflection

Find a list parameter type

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There is a class TestClass that has a field of List type. Unfortunately, we don't know a type of the List's parameter:

class TestClass {
    ...
    public List<UNKNOWN_TYPE> listField;
    ..
}

To obtain it, let's implement printParameterType method that accepts an instance of TestClass and the name of its field. The method should print a full name of the parameter type (package + class name).

Sample Input 1:

stringField

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.ParameterizedType;

import java.util.List;

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 fieldName = scanner.next();

ListParameterInspector inspector = new ListParameterInspector();

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

}

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

// Add implementation here

}

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