RSTALanguageSupport

This library contains "language support" for various languages for RSyntaxTextArea. "Language support" is a little vague, but it generally means auto-completion of function names and/or Parsers for the language (i.e. squiggle-underlining of errors in the source code).

Documentation is sparse for the moment, but should improve over time.

Besides RSyntaxTextArea and AutoComplete, this library depends on Rhino. Rhino is used to implement the code completion and syntax checking for JavaScript.

RSTALanguageSupport is available under a modified BSD license. For more information, visit https://github.com/bobbylight/RSyntaxTextArea.

Supported Languages and Status

Languages supported in this library include:

• C
  • Auto-completion for the C standard library.
  • Parameter assistance for the C standard library.
• CSS
  • Auto-completion for selectors (HTML tags only)
  • Auto-completion for CSS properties
  • Partial auto-completion for CSS values
• Groovy
  • Broken and not very useful at the moment.
• HTML
  • Auto-completion for HTML 5 tags. Suggested attributes are appropriate for the current tag.
  • Tab/attribute descriptions are extremely lacking at the moment; assistance filling them out would be more than welcome.
• Java
  • The included parser can currently parse the JDK6uXX source, but has very poor error recovery, so generally only provides a single error message per file (unless errors are very basic). It does not validate method bodies; only class structure, and extracts the names and types of members and local variables (e.g. it only does the stuff useful for code completion).
  • Auto-completion, driven from information from the Parser above. This is advanced completion and currently offers suggestions from:
    • Imported classes
    • Methods and fields.
    • Local variables (when in a method body)
  • Method parameter assistance; that is, code-complete a method name, and any parameters will have a drop-down list of fields and local variables of the proper type for that parameter. This feature is currently very limited.
  • Ctrl+Shift+O (Cmd+Shift+O on OS X) opens a "Go to Member" popup, a la Eclipse.
  • JavaOutlineTree component provides a tree view of a Java file that is updated live with edits.
• JavaScript
  • Squiggle-underlining of syntax errors, thanks to Rhino.
  • Code completion for variables and functions in the current source file, derived from the parser above. Completion choices are based on the type of the variable. Scope is honored.
  • Ctrl+Shift+O (Cmd+Shift+O on OS X) opens a "Go to Member" popup, a la Eclipse.
  • JavaScriptOutlineTree component provides a tree view of a JavaScript file that is updated live with edits.
  • Optional JSHint integration. If JSHint is installed on your machine, you can configure this library to use it for squiggle-underlining of syntax errors instead of Rhino. Point to your own .jshintrc and have full control over what issues are flagged.
• JSP
  • Auto-completion for standard JSP tags as well as HTML 5 tags.
• Perl
  • Error checking (squiggle underlining) via using "perl -c ..." on the local system. You can toggle taint mode, etc.
  • Auto-completion for build-in function names.
  • Parameter assistance for built-in functions.
  • Auto-completion for variables (only those in scope at the current caret position).
  • You can programmatically specify/override PERL5LIB.
• PHP
  • Auto-completion for HTML 5 tags and attributes, inherited from the HTML support.
  • Code completion for PHP functions.
  • Parameter assistance for PHP functions.
• Unix Shell
  • Possibly broken at the moment. Should attempt to use the local man pages for descriptions of standard shell commands if the local host is *nix, otherwise (on Windows) it defaults to short, generic descriptions. The location of the man pages that are used is configurable.
• XML
  • Ctrl+Shift+O (Cmd+Shift+O on OS X) opens a "Go to Member" popup, a la Eclipse.
  • XmlOutlineTree component provides a tree view of an XML file that is updated live with edits.

Using this Library in your Project

By far, the easiest way to use this library is by simply registering any RSyntaxTextAreas in your application with the org.fife.rsta.ac.LanguageSupportFactory. This is done as follows:

RSyntaxTextArea textArea = new RSyntaxTextArea(25, 70);
LanguageSupportFactory.get().register(textArea);

Then, whenever you call textArea.setSyntaxEditingStyle(String style), language support will automatically be installed as appropriate. If you set the style to a language with no language support, then any previous language support will be removed. If you set the style to a language with support, any existing language support will be replaced.

Language support options may vary from language to language. To tweak the functionality or appearance for a particular language, you have to edit the org.fife.rsta.ac.LanguageSupport for that language. As an example, here is how you can retrieve the LanguageSupport for Perl:

LanguageSupportFactory lsf = LanguageSupportFactory.get();
PerlLanguageSupport support = (PerlLanguageSupport)lsf.
                        getSupportFor(SyntaxConstants.SYNTAX_STYLE_PERL);

Now, you can tweak language-specific options. For example, PerlLanguageSupport has a method named setUseParensWithFunctions(boolean) that toggles whether parens are used to wrap parameters inserted via parameter assistance. This setting can be toggled to match whether you prefer to "use strict".

Concrete implementations of LanguageSupport are shared amongst all text editors that are highlighting the same language. Thus, in the above example, calling support.setUseParensWithFunctions(false) will affect all currently open instances of RSyntaxTextArea editing Perl, as well as all future instances.

Hacking

For each supported language, the corresponding LanguageSupport class can have widely-varying implementations, so you have to drill into the source for your particular language to see how things work. The Java language support, for example, scans jars on the classpath to initialize code completion. Many static languages, however, seed their code completion information from the contents of the project's data/ folder:

RSTALanguageSupport/
  data/                           Input XML for some languages
  RSTALanguageSupport/            The library source code
  RSTALanguageSupportDemo/        A demo application showing off the library

Subdirectories of data/ contain Perl scripts and input files for generating the XML files used by various languages for code completion. If you want to improve the code completion for one of these languages, this is where you have to work. But send me any updates you make! Any improvement, especially to the method and parameter descriptions, is welcome.

Sister Projects

• RSyntaxTextArea provides syntax highlighting, code folding, and many other features out-of-the-box.
• AutoComplete - Adds code completion to RSyntaxTextArea (or any other JTextComponent).
• RSTAUI - Common dialogs needed by text editing applications: Find, Replace, Go to Line, File Properties.
• SpellChecker - Adds squiggle-underline spell checking to RSyntaxTextArea.

Getting Help

• Add an issue on GitHub