org.fastnate.generator.context

Class SequenceIdGenerator

java.lang.Object

org.fastnate.generator.context.IdGenerator

org.fastnate.generator.context.SequenceIdGenerator

public class SequenceIdGenerator
extends IdGenerator

Stores the current value for a SequenceGenerator.

Author:

Tobias Liefke

Field Summary

Fields

Modifier and Type	Field and Description
private int	allocationSize The amount to increment by when allocating sequence numbers from the sequence.
private String	catalog The (optional) catalog that contains the schema of the sequence.
private long	currentSequenceValue
private GeneratorDialect	dialect The current database dialect.
private long	initialValue The value from which the sequence object is to start generating.
private long	nextValue
private String	qualifiedName The fully qualfied name of the sequence, including the optional catalog and schema name.
private boolean	relativeIds Indicates that the sequence is used when referencing existing IDs, instead of absolute IDs.
private String	schema The (optional) schema that contains the sequence.
private String	sequenceName The name of the sequence.

Constructor Summary

Constructors

Constructor and Description
SequenceIdGenerator(javax.persistence.SequenceGenerator generator, GeneratorDialect dialect, boolean relativeIds) Creates a new instance of SequenceIdGenerator.

Method Summary

Modifier and Type	Method and Description
void	addNextValue(TableStatement statement, GeneratorColumn column, 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.
void	createPreInsertStatements(StatementsWriter writer) Creates the statements that are needed in the output before IdGenerator.addNextValue(TableStatement, GeneratorColumn, Number).
int	getAllocationSize() The amount to increment by when allocating sequence numbers from the sequence.
String	getCatalog() The (optional) catalog that contains the schema of the sequence.
long	getCurrentValue() The last value returned by IdGenerator.createNextValue(Class).
GeneratorDialect	getDialect() The current database dialect.
ColumnExpression	getExpression(GeneratorTable entityTable, GeneratorColumn column, Number targetId, boolean whereExpression) Builds the reference to another entity that has the given ID.
long	getInitialValue() The value from which the sequence object is to start generating.
String	getQualifiedName() The fully qualfied name of the sequence, including the optional catalog and schema name.
String	getSchema() The (optional) schema that contains the sequence.
String	getSequenceName() The name of the sequence.
boolean	isPostIncrement() Indicates that IdGenerator.createNextValue(Class) should be called after the entity was written - as the value is not available before.
boolean	isRelativeIds() Indicates that the sequence is used when referencing existing IDs, instead of absolute IDs.
void	setCurrentValue(long currentValue) Sets a new start value.

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

createNextValue, derive

Methods inherited from class java.lang.Object

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

Field Detail

dialect

private final GeneratorDialect dialect

The current database dialect.

catalog

private final String catalog

The (optional) catalog that contains the schema of the sequence.

schema

private final String schema

The (optional) schema that contains the sequence.

sequenceName

private final String sequenceName

The name of the sequence.

qualifiedName

private final String qualifiedName

The fully qualfied name of the sequence, including the optional catalog and schema name.

relativeIds

private final boolean relativeIds

Indicates that the sequence is used when referencing existing IDs, instead of absolute IDs.

allocationSize

private final int allocationSize

The amount to increment by when allocating sequence numbers from the sequence.

initialValue

private long initialValue

The value from which the sequence object is to start generating.

nextValue

private long nextValue

currentSequenceValue

private long currentSequenceValue

Constructor Detail

SequenceIdGenerator

public SequenceIdGenerator(javax.persistence.SequenceGenerator generator,
                           GeneratorDialect dialect,
                           boolean relativeIds)

Creates a new instance of SequenceIdGenerator.

Parameters:

generator - the annotation that contains our settings

dialect - the current database dialect

relativeIds - indicates that the sequence is always used, instead of absolute IDs

Method Detail

addNextValue

public void addNextValue(TableStatement statement,
                         GeneratorColumn column,
                         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

column - 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

createPreInsertStatements

public void createPreInsertStatements(StatementsWriter writer)
                               throws IOException

Description copied from class: IdGenerator

Creates the statements that are needed in the output before IdGenerator.addNextValue(TableStatement, GeneratorColumn, Number).

Overrides:

createPreInsertStatements in class IdGenerator

Parameters:

writer - target for the created statements

Throws:

IOException - if the writer throws one

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

getExpression

public ColumnExpression getExpression(GeneratorTable entityTable,
                                      GeneratorColumn column,
                                      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

column - 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

getDialect

@Generated(value="lombok")
public GeneratorDialect getDialect()

The current database dialect.

getCatalog

@Generated(value="lombok")
public String getCatalog()

The (optional) catalog that contains the schema of the sequence.

getSchema

@Generated(value="lombok")
public String getSchema()

The (optional) schema that contains the sequence.

getSequenceName

@Generated(value="lombok")
public String getSequenceName()

The name of the sequence.

getQualifiedName

@Generated(value="lombok")
public String getQualifiedName()

The fully qualfied name of the sequence, including the optional catalog and schema name.

isRelativeIds

@Generated(value="lombok")
public boolean isRelativeIds()

Indicates that the sequence is used when referencing existing IDs, instead of absolute IDs.

getAllocationSize

@Generated(value="lombok")
public int getAllocationSize()

The amount to increment by when allocating sequence numbers from the sequence.

getInitialValue

@Generated(value="lombok")
public long getInitialValue()

The value from which the sequence object is to start generating.