Mastering Unit Testing Using Mockito and JUnit

Working with assertions

An assertion is a predicate used to verify a programmer assumption (expectation) with an actual outcome of a program implementation. For example, a programmer can expect that the addition of two positive numbers will result in a positive number. So, the programmer can write a program to add two numbers and assert the expected result with the actual result.

The org.junit.Assert package provides static overloaded methods for asserting expected and actual values for all primitive types, objects, and arrays.

This section covers the proper usage of the Assertion APIs. The following are the best practices.

Using the correct assertion

Use the correct assertion method. JUnit supports many assertion options, such as assertEquals,