org.apache.gobblin.dataset

Class Descriptor

java.lang.Object

org.apache.gobblin.dataset.Descriptor

Direct Known Subclasses:

DatasetDescriptor, PartitionDescriptor

public class Descriptor
extends Object

A descriptor is a simplified representation of a resource, which could be a dataset, dataset partition, file, etc. It is a digest or abstract, which contains identification properties of the actual resource object, such as ID, name primary keys, version, etc

When the original object has complicated inner structure and there is a requirement to send it over the wire, it's a time to define a corresponding Descriptor becomes. In this case, the Descriptor can just have minimal information enough to construct the original object on the other side of the wire

When the cost to instantiate the complete original object is high, for example, network calls are required, but the use cases are limited to the identification properties, define a corresponding Descriptor becomes handy

Field Summary

Fields

Modifier and Type	Field and Description
static com.google.gson.Gson	GSON Use gson for ser/de

Constructor Summary

Constructors

Constructor and Description
Descriptor()

Method Summary

Modifier and Type	Method and Description
Descriptor	copy()
static Descriptor	fromJson(String json) Deserialize the json string to the a Descriptor object
static <T extends Descriptor> T	fromJson(String json, Class<T> clazz) Deserialize the json string to the specified Descriptor object
static List<Descriptor>	fromJsonList(String jsonList) Deserialize the string, resulted from toJson(List), to a list of descriptors
static String	toJson(Descriptor descriptor) Serialize any Descriptor object as json string
static String	toJson(List<Descriptor> descriptors) Serialize a list of descriptors as json string
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

GSON

public static final com.google.gson.Gson GSON

Use gson for ser/de

Constructor Detail

Descriptor

public Descriptor()

Method Detail

toString

public String toString()

Overrides:

toString in class Object

copy

public Descriptor copy()

toJson

public static String toJson(Descriptor descriptor)

Serialize any Descriptor object as json string

Note: it can serialize subclasses

fromJson

public static Descriptor fromJson(String json)

Deserialize the json string to the a Descriptor object

fromJson

public static <T extends Descriptor> T fromJson(String json,
                                                Class<T> clazz)

Deserialize the json string to the specified Descriptor object

toJson

public static String toJson(List<Descriptor> descriptors)

Serialize a list of descriptors as json string

fromJsonList

public static List<Descriptor> fromJsonList(String jsonList)

Deserialize the string, resulted from toJson(List), to a list of descriptors