@NoSql

Use @NoSql to specify a non-relational (that is, no SQL) data source. EclipseLink can map non-relational data to objects and access that data through JPA.

Annotation Elements

Table 2-42 describes this annotation's elements.

Table 2-42 @NoSql Annotation Elements

Annotation Element Description Default

Annotation Element	Description	Default
`dataType`	The name of the entities structure. The purpose of the `dataType` depends on the NoSQL platform used: For MongoDB, it is the collection name that the JSON documents are stored to. For Oracle NoSQL, it is the first part of the major key value. For XML files, it is the file name. and XML messaging, use `XML`.
`dataFormat`	(Optional) The type structure (data format) in which the data is stored within the database: `INDEXED` – Maps a class to an array of values. `MAPPED` – Maps a class to a set of nested key/value pairs, a value can be an embedded map or list. Use to map to key/value stores, JSON databases, and other structured data systems. `XML` – Maps a class to an XML document. Use with XML data-stores, XML files, XML messaging systems, and other XML systems.	XML

dataType

The name of the entities structure. The purpose of the dataType depends on the NoSQL platform used:

For MongoDB, it is the collection name that the JSON documents are stored to.
For Oracle NoSQL, it is the first part of the major key value.
For XML files, it is the file name. and XML messaging, use XML.

dataFormat

(Optional) The type structure (data format) in which the data is stored within the database:

INDEXED – Maps a class to an array of values.
MAPPED – Maps a class to a set of nested key/value pairs, a value can be an embedded map or list.

Use to map to key/value stores, JSON databases, and other structured data systems.
XML – Maps a class to an XML document.

Use with XML data-stores, XML files, XML messaging systems, and other XML systems.

XML

Usage

The dataFormat depends on the NoSQL platform used:

For MongoDB, use MAPPED.
For Oracle NoSQL, use MAPPED (for key/value data) or XML (for a single XML document).
For XML files and XML messaging, use XML.

Supported Datasources

EclipseLink supports several NoSQL and EIS platforms, as well as generic NoSQL and EIS datasources through the JavaEE Connector Architecture CCI (Common Client Interface) API. You can also define your own EISPlatform subclass and JCA adapter

EclipseLink supports the following datasources:

MongoDB
Oracle NoSQL
XML Files
JMS
Oracle AQ

Examples

Example 2-78 shows using @NoSql with an XML data source.

Example 2-78 Using @NoSql Annotation with XML

@Entity
@NoSql(dataType="order")
public class Order {
  @Id
  @GeneratedValue
  @Field(name="@id")
  private long id;
  @Basic
  @Field(name="@description")
  private String description;
  @Embedded
  @Field(name="delivery-address")
  private Address deliveryAddress
  @ElementCollection
  @Field(name="orderLines/order-line")
  private List<OrderLine> orderLines;
  @ManyToOne
  @JoinField(name="customer-id")
  private Customer customer;
}
 
@Embeddable
@NoSql
public class OrderLine {
    @Field(name="@line-number")
    private int lineNumber;
    @Field(name="@item-name")
    private String itemName;
    @Field(name="@quantity")
    private int quantity;  
}

This would produce the following XML data:

<order id="4F99702B271B1948027FAF06" description="widget order">
  <deliveryAddress street="1712 Hasting Street" city="Ottawa" province="ON" postalCode="L5J1H5"/>
  <order-lines>
      <order-line lineNumber="1" itemName="widget A" quantity="5"/>
      <order-line lineNumber="2" itemName="widget B" quantity="1"/>
      <order-line lineNumber="3" itemName="widget C" quantity="2"/>
  <order-lines>
  <customer-id>4F99702B271B1948027FAF08</customer-id>
<order>

Example 2-79 shows using @NoSql with a JSON data source.

Example 2-79 Using @NoSql Annotation with JSON

@Entity
@NoSql(dataType="orders", dataFormat=DataFormatType.MAPPED)
public class Order {
  @Id
  @GeneratedValue
  @Field(name="_id")
  private long id;
  @Basic
  @Field(name="description")
  private String description;
  @Embedded
  @Field(name="deliveryAddress")
  private Address deliveryAddress
  @ElementCollection
  @Field(name="orderLines")
  private List<OrderLine> orderLines;
  @ManyToOne
  @JoinField(name="customerId")
  private Customer customer;
}
 
@Embeddable
@NoSql(dataFormat=DataFormatType.MAPPED)
public class OrderLine {
    @Field(name="lineNumber")
    private int lineNumber;
    @Field(name="itemName")
    private String itemName;
    @Field(name="quantity")
    private int quantity;  
}

This would produce the following JSON document:

{
  "_id": "4F99702B271B1948027FAF06",
  "description": "widget order",
  "deliveryAddress": {
      "street": "1712 Hasting Street",
      "city": "Ottawa",
      "province": "ON",
      "postalCode": "L5J1H5",
  },
  "orderLines": [
      {"lineNumber": "1", "itemName": "widget A", "quantity": "5"},
      {"lineNumber": "2", "itemName": "widget B", "quantity": "1"},
      {"lineNumber": "3", "itemName": "widget C", "quantity": "2"}
  ],
  "customerId": "4F99702B271B1948027FAF08",
}