@Override
    protected <T> HasSchema<T> tryWritePojoIdTo(Output output, int fieldNumber,
            Class<T> clazz, boolean registered) throws IOException
    {
        HasSchema<T> hs = getSchemaWrapper(clazz, false);
        if (hs == null || (registered && hs instanceof Lazy<?>))
            return null;
        
        output.writeString(fieldNumber, clazz.getName(), false);
        
        return hs;
    }
Used by {@link RuntimeSchema#map(Class, Class)}.
protostuff-runtime/src/main/java/io/protostuff/runtime/DefaultIdStrategy.java