com.db4o.ext

Class Db4oDatabase

java.lang.Object

com.db4o.ext.Db4oDatabase

All Implemented Interfaces:

Internal4, Db4oType

public class Db4oDatabase
extends java.lang.Object
implements Db4oType, Internal4

Class to identify a database by it's signature.

db4o UUID handling uses a reference to the Db4oDatabase object, that represents the database an object was created on.

Field Summary

Fields

Modifier and Type	Field and Description
byte[]	i_signature Field is public for implementation reasons, DO NOT TOUCH!
long	i_uuid Field is public for implementation reasons, DO NOT TOUCH! This field is badly named, it really is the creation time.
static int	STATIC_ID
static Db4oDatabase	STATIC_IDENTITY

Constructor Summary

Constructors

Constructor and Description
Db4oDatabase() constructor for persistence
Db4oDatabase(byte[] signature, long creationTime) constructor for comparison and to store new ones

Method Summary

Methods

Modifier and Type	Method and Description
int	bind(Transaction trans) make sure this Db4oDatabase is stored.
boolean	equals(java.lang.Object obj) comparison by signature.
static Db4oDatabase	generate() generates a new Db4oDatabase object with a unique signature.
long	getCreationTime()
int	getID(Transaction trans) gets the db4o ID, and may cache it for performance reasons.
byte[]	getSignature() returns the unique signature
int	hashCode()
boolean	isOlderThan(Db4oDatabase peer)
Db4oDatabase	query(Transaction trans) find a Db4oDatabase with the same signature as this one
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

STATIC_IDENTITY

public static final Db4oDatabase STATIC_IDENTITY

STATIC_ID

public static final int STATIC_ID

See Also:

Constant Field Values

i_signature

public byte[] i_signature

Field is public for implementation reasons, DO NOT TOUCH!

i_uuid

public long i_uuid

Field is public for implementation reasons, DO NOT TOUCH! This field is badly named, it really is the creation time.

Constructor Detail

Db4oDatabase

public Db4oDatabase()

constructor for persistence

Db4oDatabase

public Db4oDatabase(byte[] signature,
            long creationTime)

constructor for comparison and to store new ones

Method Detail

generate

public static Db4oDatabase generate()

generates a new Db4oDatabase object with a unique signature.

equals

public boolean equals(java.lang.Object obj)

comparison by signature.

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

getID

public int getID(Transaction trans)

gets the db4o ID, and may cache it for performance reasons.

Returns:

the db4o ID for the ObjectContainer

getCreationTime

public long getCreationTime()

getSignature

public byte[] getSignature()

returns the unique signature

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

isOlderThan

public boolean isOlderThan(Db4oDatabase peer)

bind

public int bind(Transaction trans)

make sure this Db4oDatabase is stored. Return the ID.

query

public Db4oDatabase query(Transaction trans)

find a Db4oDatabase with the same signature as this one