How do you Unit Test a Simple Getter and Setter Interface in Java?

Usually, we unit tests the logics. An interface is without implementation details. A interface is just a binding a contract, but still, we can use Mockito to mock the interface, and test it.

For example, given the following simple Setter and Getter Interface:

interface GetAndSet {
    void setValue(String name);
    String getValue();
}

We can test it like this - thanks to the Mockito mocking framework in Java. We use doAnswer method to intercept the invokation of a interface method i.e. setter, then at the time, we mock the getter.

package com.helloacm;

import lombok.val;
import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.mockito.Mockito.*;

interface GetAndSet {
    void setValue(String name);
    String getValue();
}

public class ExampleTest {
    @Test
    public void test_simple_getter_setter_interface() {
        val instance = mock(GetAndSet.class);

        doAnswer(invocation ->; {
            // or use invocation.getArgument(0);
            val name = (String)invocation.getArguments()[0];
            when(instance.getValue()).thenReturn(name);
            return null;
        }).when(instance).setValue(anyString());

        instance.setValue("HelloACM.com");
        assertEquals("HelloACM.com", instance.getValue());
    }
}

If the method we are mocking is not void - we can use when. For example:

1
2
3

when(instance.getValue()).thenAnswer(innocation -> {
     return "Hello";
});

Every little helps! I hope this helps!

Steem On!~

Reposted to The Blog of Computing

If you like my work, please consider voting for me, thanks!
https://steemit.com/~witnesses type in justyy and click VOTE

Alternatively, you could proxy to me if you are too lazy to vote!

Also: you can vote me at the tool I made: https://steemyy.com/witness-voting/?witness=justyy

Visit me at: https://steemyy.com

This page is synchronized from the post: ‘How do you Unit Test a Simple Getter and Setter Interface in Java?’

# coding, framework, java, programming, unit-testing, whalepower, witness-category

Catalogue

How do you Unit Test a Simple Getter and Setter Interface in Java?

Reposted to The Blog of Computing

Visit me at: https://steemyy.com

Your browser is out-of-date!