# AssertJ

A Java library that gives Java fluent, readable assertions.

## What is **AssertJ**?

A Java library that gives Java fluent, readable assertions.

```java
assertThat(names).contains("Ana").hasSize(3);
```

Level: Journeyman · [More Java terms at this level](https://www.ask-codey.com/glossary/subjects/java/journeyman)

Updated: October 16, 2026

Source: https://www.ask-codey.com/glossary/assertj