Improve decoupling of generated parsers and scanners from frontend code.

Somewhat related to #43 (closed) .

I am trying to add CIF as frontend to JPlag, and I thought it would be a good idea to use the existing CIF grammar. Jplag is a stand-alone plain Java program, and parsing a CIF file is just tokenizing the input file, and firing callbacks for recognized production rules, so my first guess was this should be easy.

So I took the grammar, changed the result-types of the rules, and generated the scanner, parser and hooks file. Then I had a look at the import tree, and ended up with (see the bottom of the description).

Some is expected, eg setext.runtime, and ESCET.common.java, but it drags in a lot of FRAMEWORK, EMF code for Position, right upto and including code from eclipse.swt, eclipse.ui, eclipse.core.

This seems silly for an empty scanner and parser that is to be embedded in a plain Java program. Not sure what to do here, I started thinking about introducing an interface class to seperate higher level code from the core code, but not sure.

Ideas? Thoughts?

Should I just start hacking the generated code and make it incompatible with the generator?

[[Dot file with the recursive dependencies, unfold for details.]]

// ESCET = org.eclipse.escet
// FRAMEWORK = org.eclipse.escet.app.framework
digraph C {
  "ROOT" -> "de.jplag.cif.CifParserHooks";
  "ROOT" -> "de.jplag.cif.CifParser";
  "ROOT" -> "de.jplag.cif.CifScanner";
  "de.jplag.cif.CifParserHooks" -> "ESCET.setext.runtime.Token";
  "de.jplag.cif.CifParserHooks" -> "de.jplag.cif.StructToken.CifToken";
  "de.jplag.cif.CifParserHooks" -> "ESCET.setext.runtime.Parser";
  "de.jplag.cif.CifParserHooks" -> "ESCET.common.java.Assert";
  "de.jplag.cif.CifParserHooks" -> "ESCET.common.java.Lists";
  "de.jplag.cif.CifParser" -> "ESCET.setext.runtime.Token";
  "de.jplag.cif.CifParser" -> "ESCET.common.java.Strings";
  "de.jplag.cif.CifParser" -> "ESCET.setext.runtime.ParserHooksBase";
  "de.jplag.cif.CifParser" -> "ESCET.setext.runtime.Parser";
  "de.jplag.cif.CifScanner" -> "ESCET.setext.runtime.Scanner";
  "de.jplag.cif.CifScanner" -> "ESCET.setext.runtime.Token";
  "ESCET.setext.runtime.Token" -> "ESCET.common.java.Strings";
  "ESCET.setext.runtime.Token" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.setext.runtime.Scanner" -> "ESCET.common.java.Strings";
  "ESCET.setext.runtime.Scanner" -> "ESCET.setext.runtime.exceptions.SyntaxException";
  "ESCET.setext.runtime.Scanner" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.setext.runtime.Scanner" -> "ESCET.setext.runtime.exceptions.ScanException";
  "ESCET.setext.runtime.Scanner" -> "FRAMEWORK.output.OutputProvider";
  "ESCET.setext.runtime.Scanner" -> "ESCET.common.position.metamodel.position.PositionFactory";
  "ESCET.setext.runtime.Scanner" -> "ESCET.common.java.Lists";
  "ESCET.setext.runtime.exceptions.ScanException" -> "ESCET.common.java.Strings";
  "ESCET.setext.runtime.exceptions.ScanException" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.common.position.metamodel.position.PositionFactory" -> "org.eclipse.emf.ecore.EFactory";
  "ESCET.common.position.metamodel.position.Position" -> "org.eclipse.emf.ecore.EObject";
  "FRAMEWORK.output.OutputProvider" -> "ESCET.common.java.Strings";
  "FRAMEWORK.output.OutputProvider" -> "FRAMEWORK.Application";
  "FRAMEWORK.output.OutputProvider" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.output.OutputProvider" -> "ESCET.common.java.Assert";
  "FRAMEWORK.output.OutputProvider" -> "ESCET.common.java.Lists";
  "ESCET.common.java.Strings" -> "org.apache.commons.lang.StringEscapeUtils";
  "ESCET.common.java.Strings" -> "ESCET.common.java.Lists";
  "ESCET.common.java.Strings" -> "org.apache.commons.lang.StringUtils";
  "ESCET.setext.runtime.exceptions.SyntaxException" -> "FRAMEWORK.exceptions.ApplicationException";
  "ESCET.setext.runtime.exceptions.SyntaxException" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.setext.runtime.exceptions.SyntaxException" -> "ESCET.common.java.Assert";
  "ESCET.common.java.Assert" -> "ESCET.common.java.Strings";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.output.StreamOutputComponent";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.exceptions.DependencyException";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.options.DevModeOption";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.output.OutputModeOption";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.output.OutputProvider";
  "FRAMEWORK.AppEnv" -> "ESCET.common.java.Assert";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.output.OutputMode";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.options.Options";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.output.IOutputComponent";
  "FRAMEWORK.AppEnv" -> "FRAMEWORK.io.AppStreams";
  "FRAMEWORK.Application" -> "FRAMEWORK.management.AppStatus";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.OptionDialogOption";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.GuiMode";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.OptionDialog";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.LicenseOption";
  "FRAMEWORK.Application" -> "FRAMEWORK.output.IOutputComponent";
  "FRAMEWORK.Application" -> "FRAMEWORK.io.AppStream";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.OptionValue";
  "FRAMEWORK.Application" -> "FRAMEWORK.output.StreamOutputComponent";
  "FRAMEWORK.Application" -> "org.eclipse.core.resources.IFile";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.DevModeOption";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.GuiOption";
  "FRAMEWORK.Application" -> "org.eclipse.ui.PlatformUI";
  "FRAMEWORK.Application" -> "FRAMEWORK.output.OutputModeOption";
  "FRAMEWORK.Application" -> "org.eclipse.core.resources.ResourcesPlugin";
  "FRAMEWORK.Application" -> "ESCET.common.java.Pair";
  "FRAMEWORK.Application" -> "FRAMEWORK.management.AppManager";
  "FRAMEWORK.Application" -> "org.osgi.framework.FrameworkUtil";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.OptionCategory";
  "FRAMEWORK.Application" -> "org.eclipse.core.resources.IResource";
  "FRAMEWORK.Application" -> "FRAMEWORK.exceptions.EndUserException";
  "FRAMEWORK.Application" -> "FRAMEWORK.output.OutputProvider";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.Options";
  "FRAMEWORK.Application" -> "ESCET.common.java.Lists";
  "FRAMEWORK.Application" -> "FRAMEWORK.io.AppStreams";
  "FRAMEWORK.Application" -> "ESCET.common.java.Strings";
  "FRAMEWORK.Application" -> "org.eclipse.core.runtime.Platform";
  "FRAMEWORK.Application" -> "org.eclipse.core.runtime.CoreException";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.HelpOption";
  "FRAMEWORK.Application" -> "FRAMEWORK.options.Option";
  "FRAMEWORK.Application" -> "FRAMEWORK.exceptions.ApplicationException";
  "FRAMEWORK.Application" -> "org.osgi.framework.Bundle";
  "FRAMEWORK.io.AppStream" -> "org.apache.commons.lang.ArrayUtils";
  "FRAMEWORK.io.AppStream" -> "ESCET.common.java.Strings";
  "FRAMEWORK.io.AppStream" -> "FRAMEWORK.exceptions.InputOutputException";
  "FRAMEWORK.options.OptionDialog" -> "FRAMEWORK.AppEnvData";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Composite";
  "FRAMEWORK.options.OptionDialog" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.events.SelectionEvent";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.events.SelectionAdapter";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.jface.resource.JFaceResources";
  "FRAMEWORK.options.OptionDialog" -> "FRAMEWORK.SWTUtils";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Display";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.layout.FormLayout";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Event";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.layout.FormAttachment";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Listener";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Shell";
  "FRAMEWORK.options.OptionDialog" -> "FRAMEWORK.io.MemAppStream";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.TreeItem";
  "FRAMEWORK.options.OptionDialog" -> "ESCET.common.java.Maps";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.custom.SashForm";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.graphics.Rectangle";
  "FRAMEWORK.options.OptionDialog" -> "ESCET.common.java.Sets";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.custom.ScrolledComposite";
  "FRAMEWORK.options.OptionDialog" -> "ESCET.common.java.Lists";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Text";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.layout.FormData";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Tree";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Control";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.SWT";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Label";
  "FRAMEWORK.options.OptionDialog" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.OptionDialog" -> "FRAMEWORK.exceptions.ApplicationException";
  "FRAMEWORK.options.OptionDialog" -> "org.eclipse.swt.widgets.Button";
  "FRAMEWORK.output.StreamOutputComponent" -> "ESCET.common.java.Strings";
  "FRAMEWORK.output.StreamOutputComponent" -> "FRAMEWORK.io.StdAppStream";
  "FRAMEWORK.output.StreamOutputComponent" -> "FRAMEWORK.io.AppStream";
  "FRAMEWORK.management.AppManager" -> "FRAMEWORK.Application";
  "FRAMEWORK.management.AppManager" -> "ESCET.common.java.Lists";
  "FRAMEWORK.management.AppManager" -> "ESCET.common.java.Maps";
  "FRAMEWORK.options.OptionCategory" -> "ESCET.common.java.Strings";
  "FRAMEWORK.options.OptionCategory" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.options.OptionCategory" -> "org.apache.commons.lang.StringUtils";
  "FRAMEWORK.options.OptionCategory" -> "ESCET.common.java.Sets";
  "FRAMEWORK.options.OptionCategory" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.OptionCategory" -> "ESCET.common.java.Lists";
  "FRAMEWORK.options.Options" -> "ESCET.common.java.Strings";
  "FRAMEWORK.options.Options" -> "FRAMEWORK.exceptions.InvalidOptionException";
  "FRAMEWORK.options.Options" -> "FRAMEWORK.Application";
  "FRAMEWORK.options.Options" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.options.Options" -> "ESCET.common.java.Maps";
  "FRAMEWORK.options.Options" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.Options" -> "FRAMEWORK.exceptions.ApplicationException";
  "FRAMEWORK.options.HelpOption" -> "ESCET.common.java.Strings";
  "FRAMEWORK.options.HelpOption" -> "FRAMEWORK.Application";
  "FRAMEWORK.options.HelpOption" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.options.HelpOption" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.HelpOption" -> "ESCET.common.java.Lists";
  "FRAMEWORK.options.HelpOption" -> "org.apache.commons.io.IOUtils";
  "FRAMEWORK.options.HelpOption" -> "FRAMEWORK.io.AppStream";
  "FRAMEWORK.options.Option" -> "FRAMEWORK.exceptions.InvalidOptionException";
  "FRAMEWORK.options.Option" -> "ESCET.common.java.Strings";
  "FRAMEWORK.options.Option" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.Option" -> "FRAMEWORK.exceptions.ApplicationException";
  "FRAMEWORK.options.Option" -> "org.eclipse.swt.widgets.Composite";
  "FRAMEWORK.management.AppStatus" -> "FRAMEWORK.Application";
  "FRAMEWORK.management.AppStatus" -> "FRAMEWORK.AppEnvData";
  "FRAMEWORK.options.OptionDialogOption" -> "org.eclipse.swt.widgets.Composite";
  "FRAMEWORK.options.LicenseOption" -> "FRAMEWORK.Application";
  "FRAMEWORK.options.LicenseOption" -> "FRAMEWORK.AppEnv";
  "FRAMEWORK.output.OutputModeOption" -> "FRAMEWORK.options.Options";
  "FRAMEWORK.output.OutputModeOption" -> "FRAMEWORK.options.EnumOption";
  "ESCET.common.java.Pair" -> "ESCET.common.java.Strings";
  "FRAMEWORK.options.EnumOption" -> "FRAMEWORK.exceptions.InvalidOptionException";
  "FRAMEWORK.options.EnumOption" -> "org.apache.commons.lang.ArrayUtils";
  "FRAMEWORK.options.EnumOption" -> "org.eclipse.swt.widgets.Composite";
  "FRAMEWORK.options.EnumOption" -> "org.eclipse.swt.SWT";
  "FRAMEWORK.options.EnumOption" -> "org.eclipse.swt.widgets.Button";
  "FRAMEWORK.options.EnumOption" -> "ESCET.common.java.Sets";
  "FRAMEWORK.options.EnumOption" -> "ESCET.common.java.Assert";
  "FRAMEWORK.options.EnumOption" -> "org.eclipse.swt.widgets.Group";
  "ESCET.common.java.Sets" -> "ESCET.common.java.Strings";
  "ESCET.common.java.Sets" -> "org.apache.commons.lang.StringUtils";
  "ESCET.common.java.Sets" -> "ESCET.common.java.Lists";
  "FRAMEWORK.exceptions.InvalidOptionException" -> "ESCET.common.java.Assert";
  "FRAMEWORK.AppEnvData" -> "ESCET.common.java.Strings";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.management.AppStatus";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.exceptions.DependencyException";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.console.Console";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.options.GuiMode";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.output.OutputProvider";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.options.Options";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.output.IOutputComponent";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.management.AppManager";
  "FRAMEWORK.AppEnvData" -> "FRAMEWORK.io.AppStreams";
  "FRAMEWORK.console.Console" -> "org.eclipse.swt.graphics.Color";
  "FRAMEWORK.console.Console" -> "FRAMEWORK.Application";
  "FRAMEWORK.console.Console" -> "FRAMEWORK.io.EclipseConsoleAppStream";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.IOConsoleInputStream";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.ConsolePlugin";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.IConsoleManager";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.IOConsole";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.IOConsoleOutputStream";
  "FRAMEWORK.console.Console" -> "org.eclipse.swt.widgets.Display";
  "FRAMEWORK.console.Console" -> "org.eclipse.ui.console.IConsole";
  "FRAMEWORK.console.Console" -> "FRAMEWORK.io.AppStream";
  "FRAMEWORK.console.Console" -> "FRAMEWORK.io.AppStreams";
  "FRAMEWORK.io.EclipseConsoleAppStream" -> "ESCET.common.java.Strings";
  "FRAMEWORK.io.EclipseConsoleAppStream" -> "FRAMEWORK.exceptions.InputOutputException";
  "FRAMEWORK.io.EclipseConsoleAppStream" -> "org.eclipse.ui.console.IOConsoleOutputStream";
  "FRAMEWORK.io.StdAppStream" -> "ESCET.common.java.Strings";
  "FRAMEWORK.io.StdAppStream" -> "FRAMEWORK.exceptions.InputOutputException";
  "FRAMEWORK.SWTUtils" -> "org.eclipse.swt.graphics.Rectangle";
  "FRAMEWORK.SWTUtils" -> "org.eclipse.swt.widgets.Shell";
  "FRAMEWORK.SWTUtils" -> "org.eclipse.swt.widgets.Display";
  "FRAMEWORK.SWTUtils" -> "org.eclipse.swt.SWT";
  "FRAMEWORK.SWTUtils" -> "org.eclipse.swt.widgets.Monitor";
  "ESCET.setext.runtime.Parser" -> "FRAMEWORK.Paths";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.java.Strings";
  "ESCET.setext.runtime.Parser" -> "org.apache.commons.lang.StringUtils";
  "ESCET.setext.runtime.Parser" -> "ESCET.setext.runtime.exceptions.SyntaxException";
  "ESCET.setext.runtime.Parser" -> "FRAMEWORK.exceptions.InputOutputException";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.setext.runtime.Parser" -> "FRAMEWORK.exceptions.InvalidInputException";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.java.Pair";
  "ESCET.setext.runtime.Parser" -> "FRAMEWORK.output.OutputProvider";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.java.Assert";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.java.Sets";
  "ESCET.setext.runtime.Parser" -> "ESCET.common.java.Lists";
  "ESCET.setext.runtime.Parser" -> "ESCET.setext.runtime.exceptions.ParseException";
  "FRAMEWORK.Paths" -> "ESCET.common.java.Strings";
  "FRAMEWORK.Paths" -> "org.eclipse.emf.ecore.resource.impl.URIHandlerImpl";
  "FRAMEWORK.Paths" -> "org.eclipse.emf.ecore.resource.URIHandler";
  "FRAMEWORK.Paths" -> "FRAMEWORK.exceptions.InvalidInputException";
  "FRAMEWORK.Paths" -> "org.eclipse.emf.common.util.URI";
  "FRAMEWORK.Paths" -> "ESCET.common.java.Assert";
  "FRAMEWORK.Paths" -> "ESCET.common.java.Lists";
  "FRAMEWORK.Paths" -> "org.apache.commons.lang.SystemUtils";
  "FRAMEWORK.Paths" -> "org.apache.commons.lang.StringUtils";
  "ESCET.setext.runtime.exceptions.ParseException" -> "ESCET.common.java.Strings";
  "ESCET.setext.runtime.exceptions.ParseException" -> "ESCET.common.position.metamodel.position.Position";
  "ESCET.setext.runtime.exceptions.ParseException" -> "ESCET.common.java.Assert";
}