The Geany editor is already a popular editor for Python programming.
But it has a Java side too.
Here's a few of the Java-friendly features:
• colourful syntax-highlighted Java source code• visual Java class and function navigation
• easy code compilation via the 'Build' menu option or F8
• easy class execution via the 'Build' menu option or F5
Below is a screenshot of how the classic 'Hello World' class looks in Geany.