BlueJ
A free Java Development Environment designed for beginners, used by millions worldwide.
Download and Install
Windows Version
Requires 64-bit Windows, Windows 7 or later. Also available: Standalone zip suitable for USB drives.
Ubuntu/Debian
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Dr.Java
DrJava is a light programming environment for Java dedicated for students and beginners for this language. The application offers:
code editor with syntax highlighting
integrated debugger
support for unit tests (JUnit)
bookmarks
searching and replacing text
Dr.Java Windows Version download here
The Java Development Kit(JDK)
The Java Development Kit (JDK) is one of three core technology packages used in Java programming, along with the JVM (Java Virtual Machine) and the JRE (Java Runtime Environment). The JDK allows developers to create Java programs that can be executed and run by the JVM and JRE.