Support for adding default imports

could you explain a little what you suggest?

org.codehaus.groovy.control.ResolveVisitor#DEFAULT_IMPORTS defines

java.lang.*
java.io.*
java.net.*
java.util.*
groovy.lang.*
groovy.util.*

as those packages that need no explicit import statement.

Applications that embed Groovy in order to get scripting capabilities will often provide packages that are frequently used within scripts. It would be nice if such packages could be added to the default import packages when setting up the Groovy system.

this is possible already if you have control over the compilation process... Because then you can do:

        cu.addPhaseOperation(new SourceUnitOperation() {
            public void call(SourceUnit source) throws CompilationFailedException {
                source.getAST().addImport("User",ClassHelper.make("my.company.UserDAO"));
            }
        },Phases.CONVERSION);

cu is the CompilationUnit. Is this not enough for you?

Your sample works for single classes. I've played around with sth. like

class DefaultImportSourceUnitOperation extends SourceUnitOperation {
    public void call(SourceUnit source) throws CompilationFailedException {
        source.getAST().addImportPackage("pkg1.pgk2.pkg3");
    }
}

class DefaultImportClassLoader extends GroovyClassLoader {
    protected CompilationUnit createCompilationUnit(CompilerConfiguration config, CodeSource codeSource) {
        CompilationUnit cu = super.createCompilationUnit(config, codeSource)

        cu.addPhaseOperation(new DefaultImportSourceUnitOperation(), Phases.CONVERSION)

        return cu
    }
}

which doesn't work. Probably I'm doing sth. wrong but the documentation is really poor at this time. So I had to dive deeper into this matter.

However, are there any arguments against letting configure the default import packages instead of writing AST transformation code?

"Jochen Theodorou added a comment - 17/Sep/08 05:40 PM
this is possible already if you have control over the compilation process... "

You mean we should not use GroovyShell but write our own class which will replace it, right?
In this way we will be able to force it to use our own ClassLoader not default GroovyClassLoader.

addImport() works but addImportPackage() not
It is a bit incontinent, but as API will have limited number of classes I can use addImport()

By the way do you know how to stop users from using some classes?
In our application we have classes with set and get methods. We would like to give users only read access in scripts, so the public API classes will have only get methods. I would like to prevent users from importing and using classes from some packages. Is it possible in some easy way by extending GroovyClassLoader or other class?

Alexander... how would you define the default import packages?

Arek, if you use a subclass of GroovyClassLoader you can do it like Alexander did.

As for addImportPackage(), this wants to have the packe plus ".". That is because of historic reasons, so don't ask Anyway, if you want to import foo.bar.*, then you have to call addImportPackage("foo.bar.")

As for preventing a user to use certain classes. I suggest you add a phase operation that checks each ClassExpression for a usage of that class. In the Groovy ditstribution since 1.6-beta2 and 1.5.7 you should find in the examples directory an example called ArithmeticShell. This shell does for example forbid the usage of certain classes. So look at that example.

Great, thanks for a tip with "." Now it works.
I will also look at this examples.

Thanks a lot.