Testing Private methods (with Collection parameter) - JUnit

Class having a private method which needs to be tested:

package com.practice;

import java.lang.reflect.InvocationTargetException;

import java.lang.reflect.Method;

import java.util.ArrayList;

import java.util.List;

import junit.framework.Assert;

import org.junit.Before;

import org.junit.Test;

public class ClassWithPrivateMethod {

    public static void main(String[] args) {

        // ....

    }

   

    private void findOwnerForThisAddress(List<People> peopleList, Address address) {

        // Some logic find out who out of peopleList stays in this address.

    }

}

class People {

   

}

class Address {

   

}

JUnit test class to test the private method: 

class PrivateMethodTest {

    ClassWithPrivateMethod classOfInterest;

   

    @Before

    public void setUp() throws Exception {

        classOfInterest = new ClassWithPrivateMethod();

    }

   

    @Test

    public void testFindOwnerForThisAddress() {

        Address address = new Address();

        List<People> peopleList = new ArrayList<People>();

       

        try {

            Method methodOfInterest;

            methodOfInterest = ClassWithPrivateMethod.class.getDeclaredMethod("findOwnerForThisAddress", List.class, Address.class);

            methodOfInterest.setAccessible(true);

           

            methodOfInterest.invoke(classOfInterest, peopleList, address);

           

        } catch (SecurityException e) {

            Assert.fail(e.getMessage());

        } catch (NoSuchMethodException e) {

            Assert.fail(e.getMessage());

        } catch (IllegalArgumentException e) {

            e.printStackTrace();

            Assert.fail(e.getMessage());

        } catch (IllegalAccessException e) {

            Assert.fail(e.getMessage());

        } catch (InvocationTargetException e) {

            e.printStackTrace();

            Assert.fail(e.getMessage());

        }

    }

}