Package com.db4o.internal

Class Config4Field

java.lang.Object

com.db4o.internal.Config4Abstract

com.db4o.internal.Config4Field

All Implemented Interfaces:

ObjectField, DeepClone

public class Config4Field
extends Config4Abstract
implements ObjectField, DeepClone

Field Summary

Fields inherited from class com.db4o.internal.Config4Abstract

_config

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Config4Field(Config4Class a_class, KeySpecHashtable4 config)

Method Summary

Modifier and Type	Method	Description
java.lang.Object	deepClone(java.lang.Object param)	The parameter allows passing one new object so parent references can be corrected on children.
void	indexed(boolean flag)	turns indexing on or off.
void	initOnUp(Transaction systemTrans, FieldMetadata fieldMetadata)
void	rename(java.lang.String newName)	renames a field of a stored class.
boolean	used()
void	used(boolean flag)

Methods inherited from class com.db4o.internal.Config4Abstract

cascadeOnActivate, cascadeOnActivate, cascadeOnDelete, cascadeOnDelete, cascadeOnUpdate, cascadeOnUpdate, equals, getName, hashCode, putThreeValued, putThreeValuedInt, setName

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.db4o.config.ObjectField

cascadeOnActivate, cascadeOnDelete, cascadeOnUpdate

Constructor Detail

Config4Field

protected Config4Field(Config4Class a_class,
                       KeySpecHashtable4 config)

Method Detail

deepClone

public java.lang.Object deepClone(java.lang.Object param)

Description copied from interface: DeepClone

The parameter allows passing one new object so parent references can be corrected on children.

Specified by:

deepClone in interface DeepClone

rename

public void rename(java.lang.String newName)

Description copied from interface: ObjectField

renames a field of a stored class.

Use this method to refactor classes.

In client-server environment this setting should be used on both client and server.

This setting can NOT be applied to an open object container.

Specified by:

rename in interface ObjectField

Parameters:

newName - the new field name.

indexed

public void indexed(boolean flag)

Description copied from interface: ObjectField

turns indexing on or off.

Field indices dramatically improve query performance but they may considerably reduce storage and update performance.
The best benchmark whether or not an index on a field achieves the desired result is the completed application - with a data load that is typical for it's use.

This configuration setting is only checked when the ObjectContainer is opened. If the setting is set to true and an index does not exist, the index will be created. If the setting is set to false and an index does exist the index will be dropped.

In client-server environment this setting should be used on both client and server.

If this setting is applied to an open ObjectContainer it will take an effect on the next time ObjectContainer is opened.

Specified by:

indexed in interface ObjectField

Parameters:

flag - specify true or false to turn indexing on for this field

initOnUp

public void initOnUp(Transaction systemTrans,
                     FieldMetadata fieldMetadata)

used

public void used(boolean flag)

used

public boolean used()