AST for current selected code in eclipse editor?

Question

I need to get the AST for the current selection in the java editor fo eclipse. Basically I want to convert the selected java code in to some other form(maybe some other lang

Answer 1

Use the method org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.getActiveEditorJavaInput(). That returns the Java element edited in the current active editor. The return type is org.eclipse.jdt.core.IJavaElement, but if it's a Java file that's being edited, the run time type will be org.eclipse.jdt.core.ICompilationUnit.

To get the AST, i.e., the org.eclipse.jdt.core.dom.CompilationUnit, you can use the following code:

public static CompilationUnit getCompilationUnit(ICompilationUnit icu,
        IProgressMonitor monitor) {
    final ASTParser parser = ASTParser.newParser(AST.JLS3);
    parser.setSource(icu);
    parser.setResolveBindings(true);
    final CompilationUnit ret = (CompilationUnit) parser.createAST(monitor);
    return ret;
}

Keep in mind that this is for Java >= 5. For earlier versions you'll need to switch the argument to ASTParser.newParser().

I realize that this question was answered but I wanted to shed light on the EditorUtility class, which is quite useful here.