BlueJ vs DrJava

BlueJ is a free development environment for building Java programs, designed for beginners and teaching. It runs on Windows, macOS and Linux, with current downloads requiring a 64-bit operating system. Its interactive tools let users create and inspect objects, call methods, and evaluate Java expressions without compiling. In the editor, scope highlighting distinguishes code blocks and can help reveal misplaced curly brackets. BlueJ 6.0.0 added Kotlin editing and execution, though some Kotlin features, including code completion, are not supported. Documentation includes a Git teamwork tutorial for BlueJ 4 and later. Third parties can add functionality through an extensions API; the listed extensions page covers BlueJ 4 and older, while BlueJ 5.0.0 rewrote the API. The free Blueroom site offers teaching resources for educators. BlueJ directs software questions to its FAQ, technical support contact and bug database, and says it aims to respond to technical support requests within one working day.

DrJava is a free, open-source development environment for writing Java programs, designed primarily for students. Its intelligent editor supports coding, while the Interactions pane lets users evaluate Java code interactively. The environment includes JUnit testing, a source-level debugger and Javadoc generation for source files. It runs on Windows, macOS and Linux under a standard BSD open-source license. The current beta is compatible with Java 8, identified by the project page as the only supported version of traditional Java. That beta is distributed only as a JAR, which the page says is intended to reduce cross-platform compatibility issues. The Eclipse plugin is described as very old and compatible only with Eclipse versions from the same era. The Linux FAQ reports an incompatibility with the Compiz window manager and recommends disabling Compiz if it occurs. Bug reports and feature requests require a SourceForge account login. The Free plan costs nothing, with no free trial listed.