org.datanucleus.metadata

Class IdentityStrategy

java.lang.Object

org.datanucleus.metadata.IdentityStrategy

All Implemented Interfaces:

Serializable

public class IdentityStrategy
extends Object
implements Serializable

Representation of the values for identity "strategy". Would have been nice to have this as an enum, but we need to allow for CUSTOM types

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static IdentityStrategy	CUSTOM An extension strategy not in the standard JDO/JPA list.
static IdentityStrategy	IDENTITY strategy="identity" in JDO and JPA The value "identity" specifies that the column identified as the key column is managed by the database as an autoincrementing identity type.
static IdentityStrategy	INCREMENT strategy="increment" in JDO and "table" in JPA The value "increment" specifies a strategy that simply finds the largest key already in the database and increments the key value for new instances.
static IdentityStrategy	NATIVE strategy="native" in JDO, and "auto" in JPA The value "native" allows the JDO implementation to pick the most suitable strategy based on the underlying database.
static IdentityStrategy	SEQUENCE strategy="sequence" in JDO and JPA The value "sequence" specifies that a named database sequence is used to generate key values for the table.
static IdentityStrategy	UUIDHEX strategy="uuid-hex" The value "uuid-hex" specifies a strategy that generates a 128-bit UUID unique within a network (the IP address of the machine running the application is part of the id) and represents the result as a 32-character String.
static IdentityStrategy	UUIDSTRING strategy="uuid-string" The value "uuid-string" specifies a strategy that generates a 128-bit UUID unique within a network (the IP address of the machine running the application is part of the id) and represents the result as a 16-character String.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object o)
String	getCustomName() Accessor for the custom name (if using strategy type of CUSTOM).
static IdentityStrategy	getIdentityStrategy(String value) Gets an IdentityStrategy for the given value argument.
int	getType() Accessor for the type.
int	hashCode()
String	toString() Returns a string representation of the object.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

NATIVE

public static final IdentityStrategy NATIVE

strategy="native" in JDO, and "auto" in JPA The value "native" allows the JDO implementation to pick the most suitable strategy based on the underlying database.

SEQUENCE

public static final IdentityStrategy SEQUENCE

strategy="sequence" in JDO and JPA The value "sequence" specifies that a named database sequence is used to generate key values for the table. If sequence is used, then the sequence-name attribute is required.

IDENTITY

public static final IdentityStrategy IDENTITY

strategy="identity" in JDO and JPA The value "identity" specifies that the column identified as the key column is managed by the database as an autoincrementing identity type.

INCREMENT

public static final IdentityStrategy INCREMENT

strategy="increment" in JDO and "table" in JPA The value "increment" specifies a strategy that simply finds the largest key already in the database and increments the key value for new instances. It can be used with integral column types when the JDO application is the only database user inserting new instances.

UUIDSTRING

public static final IdentityStrategy UUIDSTRING

strategy="uuid-string" The value "uuid-string" specifies a strategy that generates a 128-bit UUID unique within a network (the IP address of the machine running the application is part of the id) and represents the result as a 16-character String.

UUIDHEX

public static final IdentityStrategy UUIDHEX

strategy="uuid-hex" The value "uuid-hex" specifies a strategy that generates a 128-bit UUID unique within a network (the IP address of the machine running the application is part of the id) and represents the result as a 32-character String.

CUSTOM

public static final IdentityStrategy CUSTOM

An extension strategy not in the standard JDO/JPA list. Will have the "customName" set to the chosen strategy. This object only exists for use in the equals() method to check if something is CUSTOM.

Method Detail

getCustomName

public String getCustomName()

Accessor for the custom name (if using strategy type of CUSTOM).

Returns:

Custom name

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

toString

public String toString()

Returns a string representation of the object.

Overrides:

toString in class Object

Returns:

a string representation of the object.

getType

public int getType()

Accessor for the type.

Returns:

Type

getIdentityStrategy

public static IdentityStrategy getIdentityStrategy(String value)

Gets an IdentityStrategy for the given value argument.

Parameters:

value - the String representation of IdentityStrategy

Returns:

the IdentityStrategy corresponding to the value argument. NATIVE IdentityStrategy is returned if the value argument is null or no corresponding strategy was found