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

Java EE 5 SDK

javax.persistence
Enum FetchType

java.lang.Object
  extended by java.lang.Enum<FetchType>
      extended by javax.persistence.FetchType
All Implemented Interfaces:
Serializable, Comparable<FetchType>

public enum FetchType
extends Enum<FetchType>

Defines strategies for fetching data from the database. The EAGER strategy is a requirement on the persistence provider runtime that data must be eagerly fetched. The LAZY strategy is a hint to the persistence provider runtime that data should be fetched lazily when it is first accessed. The implementation is permitted to eagerly fetch data for which the LAZY strategy hint has been specified. In particular, lazy fetching might only be available for Basic mappings for which property-based access is used.

   Example:
   @Basic(fetch=LAZY)
   protected String getName() { return name; }
 

Since:
Java Persistence 1.0

Enum Constant Summary
EAGER
          Defines that data must be eagerly fetched
LAZY
          Defines that data can be lazily fetched
 
Method Summary
static FetchType valueOf(String name)
          Returns the enum constant of this type with the specified name.
static FetchType[] values()
          Returns an array containing the constants of this enum type, in the order they're declared.
 
Methods inherited from class java.lang.Enum
clone, compareTo, equals, getDeclaringClass, hashCode, name, ordinal, toString, valueOf
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Enum Constant Detail

LAZY

public static final FetchType LAZY
Defines that data can be lazily fetched


EAGER

public static final FetchType EAGER
Defines that data must be eagerly fetched

Method Detail

values

public static final FetchType[] values()
Returns an array containing the constants of this enum type, in the order they're declared. This method may be used to iterate over the constants as follows:
for(FetchType c : FetchType.values())
        System.out.println(c);

Returns:
an array containing the constants of this enum type, in the order they're declared

valueOf

public static FetchType valueOf(String name)
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:
name - the name of the enum constant to be returned.
Returns:
the enum constant with the specified name
Throws:
IllegalArgumentException - if this enum type has no constant with the specified name

Java EE 5 SDK

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Copyright 2006 Sun Microsystems, Inc. All rights reserved.