code: public InterfaceMethodRefConstant addInterfaceRef(String className,
                                                      String name,
                                                      String type)
    {
      InterfaceMethodRefConstant entry = getInterfaceRef(className, name, type);
  
      if (entry != null)
        return entry;
  
      ClassConstant classEntry = addClass(className);
      NameAndTypeConstant typeEntry = addNameAndType(name, type);
  
      entry = new InterfaceMethodRefConstant(this, _entries.size(),
                                             classEntry.getIndex(),
                                             typeEntry.getIndex());
  
      addConstant(entry);
  
      return entry;
    }
docs: Adds an interface ref constant.