import org.apache.hadoop.tools.rumen.datatypes.DataType; //导入依赖的package包/类
public JsonObjectMapperWriter(OutputStream output, boolean prettyPrint) throws IOException {
  ObjectMapper mapper = new ObjectMapper();
  mapper.configure(
      SerializationConfig.Feature.CAN_OVERRIDE_ACCESS_MODIFIERS, true);

  // define a module
  SimpleModule module = new SimpleModule("Default Serializer",  
                                         new Version(0, 1, 1, "FINAL"));
  // add various serializers to the module
  //   add default (all-pass) serializer for all rumen specific data types
  module.addSerializer(DataType.class, new DefaultRumenSerializer());
  //   add a serializer to use object.toString() while serializing
  module.addSerializer(ID.class, new ObjectStringSerializer<ID>());
  
  // register the module with the object-mapper
  mapper.registerModule(module);

  mapper.getJsonFactory();
  writer = mapper.getJsonFactory().createJsonGenerator(
      output, JsonEncoding.UTF8);
  if (prettyPrint) {
    writer.useDefaultPrettyPrinter();
  }
}
 

import org.apache.hadoop.tools.rumen.datatypes.DataType; //导入依赖的package包/类
public void serialize(DataType object, JsonGenerator jGen, SerializerProvider sProvider) 
throws IOException, JsonProcessingException {
  Object data = object.getValue();
  if (data instanceof String) {
    jGen.writeString(data.toString());
  } else {
    jGen.writeObject(data);
  }
}
 

import org.apache.hadoop.tools.rumen.datatypes.DataType; //导入依赖的package包/类
@Override
public DataType<?> parseJobProperty(String key, String value) {
  return new DefaultDataType(value);
}
 

import org.apache.hadoop.tools.rumen.datatypes.DataType; //导入依赖的package包/类
/**
 * Parse the specified job configuration key-value pair.
 * 
 * @return Returns a {@link DataType} if this parser can parse this value.
 *         Returns 'null' otherwise.
 */
public DataType<?> parseJobProperty(String key, String value);