Though there are hundreds of tools that make Java development easier, the key tool for most Java developers is the Integrated Development Environment (IDE), which provides a tight-knit system designed to maximize developer productivity. The most popular IDE for Java development is the open-source Eclipse software package. It has a plethora of built-in tools, such as build automation, debugger interfaces, source code highlighting, code refactoring tools, unit test reporting, source control and build status monitoring for continuous integration.
In addition to Eclipse, other major IDEs available include IntelliJ and NetBeans. Most of these IDEs are extensible via plugins.
An essential plugin in the Java developer's arsenal is the FindBugs static analyzer, which scans Java projects to find potential bugs in source code. JUnit is another tool with good IDE integration that is used to catch bugs and regressions. It is essential for test-driven development, a popular programming development method amongst Java developers.
Java developers also often use continuous integration build systems such as Jenkins. Jenkins is a particularly extensible continuous integration tool and is itself written in Java. Along with hundreds of other plugins, Jenkins features an Eclipse plugin that announces the build status to the developer, alerting her when a build fails.