RSyntaxTextArea is a customizable, syntax highlighting text component for Java Swing applications. Out of the box, it supports syntax highlighting for 50+ programming languages, code folding, search and replace, and has add-on libraries for code completion and spell checking. Syntax highlighting for additional languages can be added via tools such as JFlex.

RSyntaxTextArea is available under a BSD 3-Clause license. For more information, visit http://bobbylight.github.io/RSyntaxTextArea/.

Available in the Maven Central repository (com.fifesoft:rsyntaxtextarea:XXX). SNAPSHOT builds of the in-development, unreleased version are hosted on Sonatype.

RSyntaxTextArea uses Gradle to build. To compile, run all unit tests, and create the jar, run:

./gradlew build --warning-mode all

RSTA 3.0 and newer requires Java 8 to compile and run. If you need Java 6 compatibility, you'll need to use a 2.6.x version.

RSyntaxTextArea is simply a subclass of JTextComponent, so it can be dropped into any Swing application with ease.

import javax.swing.*;
import java.awt.BorderLayout;

import org.fife.ui.rtextarea.*;
import org.fife.ui.rsyntaxtextarea.*;

public class TextEditorDemo extends JFrame {

    public TextEditorDemo() {

        JPanel cp = new JPanel(new BorderLayout());

        RSyntaxTextArea textArea = new RSyntaxTextArea(20, 60);
        textArea.setSyntaxEditingStyle(SyntaxConstants.SYNTAX_STYLE_JAVA);
        textArea.setCodeFoldingEnabled(true);
        RTextScrollPane sp = new RTextScrollPane(textArea);
        cp.add(sp);

        setContentPane(cp);
        setTitle("Text Editor Demo");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        pack();
        setLocationRelativeTo(null);

    }

    public static void main(String[] args) {
        // Start all Swing applications on the EDT.
        SwingUtilities.invokeLater(() -> new TextEditorDemo().setVisible(true));
    }

}

RSyntaxTextArea provides syntax highlighting, code folding, and many other features out-of-the-box, but when building a code editor you often want to go further. Below is a list of small add-on libraries that add more complex functionality:

• AutoComplete - Adds code completion to RSyntaxTextArea (or any other JTextComponent).
• RSTALanguageSupport - Code completion for RSTA for the following languages: Java, JavaScript, HTML, PHP, JSP, Perl, C, Unix Shell. Built on both RSTA and AutoComplete.
• SpellChecker - Adds squiggle-underline spell checking to RSyntaxTextArea.
• RSTAUI - Common dialogs needed by text editing applications: Find, Replace, Go to Line, File Properties.

• Add an issue on GitHub
• Peruse the wiki
• Check the project's home page