ÜB-Praxis-Abstiegsparser für X-Leer org.eclipse.xtext.ui.shared.xtextBuilder org.eclipse.ui.externaltools.ExternalToolBuilder LaunchConfigHandle <project>/.externalToolBuilders/JFlex Ant AS [Builder].launch org.eclipse.jdt.core.javabuilder pi.eclipse.cle.CupLexNature org.eclipse.jdt.core.javanature org.eclipse.xtext.ui.shared.xtextNature