How to specify a CodeSet for WChar string from a CORBA client

Question

This question is related to another question with which I have been struggling: How to access CORBA interface without IDL or late-bound invoke remoting methods

I'm really stumped on how to get past this error about the CodeSet not being specified. I have been tracing into the IIOP code trying to figure out how the CodeSet can be specified, and it looks like it could be specified with a tagged component associated with the profile. Being unfamiliar with CORBA, I don't know what a tagged component is or what a profile is or how to control them, but I suspect that it may be influenced by creating a portable object interceptor, at which point I could add a tagged CodeSet component to the profile, if that means anything. I'm just going by what I can learn from the IIOP.NET code and Google.

Could someone please help me understand and hopefully control this? If the server is a black box and I need to write a client to call a method that outputs a string, how do I tell IIOP.NET what WChar CodeSet to use so it doesn't give me an error about it being unspecified. I tried OverrideDefaultCharSets from the client, but that didn't seem to have any effect. The IIOP sample code for that function shows it being used on the server side.

score 0 · Accepted Answer · answered May 18 '11 at 16:47

This was a real pain to work out, but I got it:

class MyOrbInitializer : omg.org.PortableInterceptor.ORBInitializer
{
    public void post_init(omg.org.PortableInterceptor.ORBInitInfo info)
    {
        // Nothing to do
    }

    public void pre_init(omg.org.PortableInterceptor.ORBInitInfo info)
    {
        omg.org.IOP.Codec codec = info.codec_factory.create_codec(
            new omg.org.IOP.Encoding(omg.org.IOP.ENCODING_CDR_ENCAPS.ConstVal, 1, 2));
        Program.m_codec = codec;
    }
}


class Program
{
    public static omg.org.IOP.Codec m_codec;

    static void Main(string[] args)
    {
        IOrbServices orb = OrbServices.GetSingleton();
        orb.OverrideDefaultCharSets(CharSet.UTF8, WCharSet.UTF16);
        orb.RegisterPortableInterceptorInitalizer(new MyOrbInitializer());
        orb.CompleteInterceptorRegistration();
...
        MarshalByRefObject objRef = context.resolve(names);
        string origObjData = orb.object_to_string(objRef);
        Ch.Elca.Iiop.CorbaObjRef.Ior iorObj = new Ch.Elca.Iiop.CorbaObjRef.Ior(origObjData);
        CodeSetComponentData cscd = new CodeSetComponentData(
            (int)Ch.Elca.Iiop.Services.CharSet.UTF8,
            new int[] { (int)Ch.Elca.Iiop.Services.CharSet.UTF8 },
            (int)Ch.Elca.Iiop.Services.WCharSet.UTF16,
            new int[] { (int)Ch.Elca.Iiop.Services.WCharSet.UTF16 });
        omg.org.IOP.TaggedComponent codesetcomp = new omg.org.IOP.TaggedComponent(
            omg.org.IOP.TAG_CODE_SETS.ConstVal, m_codec.encode_value(cscd));
        iorObj.Profiles[0].TaggedComponents.AddComponent(codesetcomp);
        string newObjData = iorObj.ToString();
        MarshalByRefObject newObj = (MarshalByRefObject)orb.string_to_object(newObjData);
        ILicenseInfo li = (ILicenseInfo)newObj;
...
    }

Unfortunately in my case the problem remained that the byte ordering was backwards too, so I had to go with an entirely different solution based on just getting bytes back and manually converting them to a string instead of getting string directly.

How to specify a CodeSet for WChar string from a CORBA client

1 Answers1