@Override
                protected void transfer(Pipe pipe, Input input, Output output) throws IOException
                {
                    for (int number = input.readFieldNumber(MapSchema.this);;
                    number = input.readFieldNumber(MapSchema.this))
                    {
                        switch (number)
                        {
                            case 0:
                                return;
                            case 1:
                                output.writeObject(number, pipe, entryPipeSchema, true);
                                break;
                            default:
                                throw new ProtostuffException("The map was incorrectly " +
                                        "serialized.");
                        }
                    }
                }
The pipe schema of the {@link Map}.
protostuff-collectionschema/src/main/java/io/protostuff/MapSchema.java