org.fastnate.generator.context

Class IdentityValue

java.lang.Object

org.fastnate.generator.context.IdGenerator

org.fastnate.generator.context.IdentityValue

public class IdentityValue
extends IdGenerator

Contains the current value for a primary key of type GenerationType.IDENTITY.

Author:

Tobias Liefke

Field Summary

Fields

Modifier and Type	Field and Description
private GeneratorColumn	column
private GeneratorContext	context
private long	currentValue
private boolean	needsAlignment
private GeneratorTable	table

Constructor Summary

Constructors

Constructor and Description
IdentityValue(GeneratorContext context, GeneratorTable table, GeneratorColumn column)

Method Summary

Modifier and Type	Method and Description
void	addNextValue(TableStatement statement, GeneratorColumn tableColumn, Number value) Adds the generated value to the given statement.
void	alignNextValue(StatementsWriter writer) Creates all statements that are necessary to set the next value created from the database is currentValue + 1.
long	createNextValue() Resolves the next value of this generator.
long	getCurrentValue() The last value returned by IdGenerator.createNextValue(Class).
ColumnExpression	getExpression(GeneratorTable entityTable, GeneratorColumn targetColumn, Number targetId, boolean whereExpression) Builds the reference to another entity that has the given ID.
boolean	isPostIncrement() Indicates that IdGenerator.createNextValue(Class) should be called after the entity was written - as the value is not available before.
void	setCurrentValue(long currentValue) Sets a new start value.

Methods inherited from class org.fastnate.generator.context.IdGenerator

createNextValue, createPreInsertStatements, derive

Methods inherited from class java.lang.Object

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

Field Detail

context

private final GeneratorContext context

table

private final GeneratorTable table

column

private final GeneratorColumn column

currentValue

private long currentValue

needsAlignment

private boolean needsAlignment

Constructor Detail

IdentityValue

public IdentityValue(GeneratorContext context,
                     GeneratorTable table,
                     GeneratorColumn column)

Method Detail

addNextValue

public void addNextValue(TableStatement statement,
                         GeneratorColumn tableColumn,
                         Number value)

Description copied from class: IdGenerator

Adds the generated value to the given statement. Depending on the generator this may add the value itself or a reference to the value.

Specified by:

addNextValue in class IdGenerator

Parameters:

statement - the current insert statement

tableColumn - the ID column of the current table

value - the current value of the column, previously generated with IdGenerator.createNextValue()

alignNextValue

public void alignNextValue(StatementsWriter writer)
                    throws IOException

Description copied from class: IdGenerator

Creates all statements that are necessary to set the next value created from the database is currentValue + 1.

Specified by:

alignNextValue in class IdGenerator

Parameters:

writer - the target of the created statements

Throws:

IOException - if the writer throws one

createNextValue

public long createNextValue()

Description copied from class: IdGenerator

Resolves the next value of this generator.

Specified by:

createNextValue in class IdGenerator

Returns:

the generated value

getExpression

public ColumnExpression getExpression(GeneratorTable entityTable,
                                      GeneratorColumn targetColumn,
                                      Number targetId,
                                      boolean whereExpression)

Description copied from class: IdGenerator

Builds the reference to another entity that has the given ID.

Specified by:

getExpression in class IdGenerator

Parameters:

entityTable - the main table of the entity

targetColumn - the name of the column of the ID

targetId - the current value of the ID

whereExpression - indicates if this expression is needed for a "SELECT ... WHERE ..." - some dialects behave differently in this situation

Returns:

the expression for selecting the ID

isPostIncrement

public boolean isPostIncrement()

Description copied from class: IdGenerator

Indicates that IdGenerator.createNextValue(Class) should be called after the entity was written - as the value is not available before.

Specified by:

isPostIncrement in class IdGenerator

Returns:

true if the database increments the value _after_ the insert statement was executed, true if it is incremented before or during the execution

setCurrentValue

public void setCurrentValue(long currentValue)

Description copied from class: IdGenerator

Sets a new start value.

Specified by:

setCurrentValue in class IdGenerator

Parameters:

currentValue - the current value - most likely as extracted from the target database

getCurrentValue

public long getCurrentValue()

Description copied from class: IdGenerator

The last value returned by IdGenerator.createNextValue(Class).

Specified by:

getCurrentValue in class IdGenerator

Returns:

the current value