import com.sun.corba.se.spi.ior.iiop.CodeSetsComponent; //导入依赖的package包/类
protected void performCodeSetNegotiation(CorbaMessageMediator messageMediator)
{
    CorbaConnection conn =
        (CorbaConnection) messageMediator.getConnection();
    IOR ior =
        ((CorbaContactInfo)messageMediator.getContactInfo())
        .getEffectiveTargetIOR();
    GIOPVersion giopVersion = messageMediator.getGIOPVersion();

    // XXX This seems to be a broken double checked locking idiom: FIX IT!

    // conn.getCodeSetContext() is null when no other requests have
    // been made on this connection to trigger code set negotation.
    if (conn != null &&
        conn.getCodeSetContext() == null &&
        !giopVersion.equals(GIOPVersion.V1_0)) {

        synchronized(conn) {
            // Double checking.  Don't let any other
            // threads use this connection until the
            // code sets are straight.
            if (conn.getCodeSetContext() != null)
                return;

            // This only looks at the first code set component.  If
            // there can be multiple locations with multiple code sets,
            // this requires more work.
            IIOPProfileTemplate temp =
                (IIOPProfileTemplate)ior.getProfile().
                getTaggedProfileTemplate();
            Iterator iter = temp.iteratorById(TAG_CODE_SETS.value);
            if (!iter.hasNext()) {
                // Didn't have a code set component.  The default will
                // be to use ISO8859-1 for char data and throw an
                // exception if wchar data is used.
                return;
            }

            // Get the native and conversion code sets the
            // server specified in its IOR
            CodeSetComponentInfo serverCodeSets
                = ((CodeSetsComponent)iter.next()).getCodeSetComponentInfo();

            // Perform the negotiation between this ORB's code sets and
            // the ones from the IOR
            CodeSetComponentInfo.CodeSetContext result
                = CodeSetConversion.impl().negotiate(
                      conn.getBroker().getORBData().getCodeSetComponentInfo(),
                      serverCodeSets);

            conn.setCodeSetContext(result);
        }
    }
}