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Basic (Java EE 5 SDK) - Java Platform, Enterprise Edition v5.0 API Specifications

Java EE 5 SDK

javax.persistence
Annotation Type Basic


@Target(value={METHOD,FIELD})
@Retention(value=RUNTIME)
public @interface Basic

The Basic annotation is the simplest type of mapping to a database column. The Basic annotation can be applied to a persistent property or instance variable of any of the following types: Java primitive types, wrappers of the primitive types, String, java.math.BigInteger, java.math.BigDecimal, java.util.Date, java.util.Calendar, java.sql.Date, java.sql.Time, java.sql.Timestamp, byte[], Byte[], char[], Character[], enums, and any other type that implements Serializable.

The use of the Basic annotation is optional for persistent fields and properties of these types.

Since:
Java Persistence 1.0

Optional Element Summary
 FetchType fetch
          (Optional) Defines whether the value of the field or property should be lazily loaded or must be eagerly fetched.
 boolean optional
          (Optional) Defines whether the value of the field or property may be null.
 

fetch

public abstract FetchType fetch
(Optional) Defines whether the value of the field or property should be lazily loaded or must be eagerly fetched. The EAGER strategy is a requirement on the persistence provider runtime that the value must be eagerly fetched. The LAZY strategy is a hint to the persistence provider runtime. If not specified, defaults to EAGER.

Default:
EAGER

optional

public abstract boolean optional
(Optional) Defines whether the value of the field or property may be null. This is a hint and is disregarded for primitive types; it may be used in schema generation. If not specified, defaults to true.

Default:
true

Java EE 5 SDK

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