Hamcrest Assertions

In the last chapter, we learned that Hamcrest (an anagram of the word matchers) is a newer, more expressive framework for writing matcher objects that allow match rules to be defined declaratively. It supports customized assertion matches.

Now, let’s learn more about Hamcrest and learn about its code implementation.

Hamcrest assertion arguments

• The first argument in a Hamcrest assertion is the actual expression—the value we want to verify (often a method call to the underlying system).
• The second argument is a matcher. A matcher is a static method call that allows us to compare the results of an expression against an actual value.