"sfAddAttribute"));
"sfAddAttribute name:'"+name+"'"));
     public synchronized Object sfAddAttribute(Object name, Object value)         throws SmartFrogContextException{         if ((name == null) || (value == null)) {           if (name == null) {               throw new SmartFrogContextException(               MessageUtil.formatMessage(MessageKeys.MSG_NULL_DEF_METHOD, "'name'",                                         "sfAddAttribute") );           }           if (value == null) {               throw new SmartFrogContextException(               MessageUtil.formatMessage(MessageKeys.MSG_NULL_DEF_METHOD, "'value'",                                         "sfAddAttribute"));           }             return null;         }         if (this.containsKey(name)) {             throw new SmartFrogContextException(             MessageUtil.formatMessage(MessageKeys.MSG_REPEATED_ATTRIBUTE, name));         }         return this.put(name, value);     }