org.tentackle.pdo

Class Join<T extends PersistentDomainObject<T>,J extends PersistentDomainObject<J>>

java.lang.Object

org.tentackle.pdo.Join<T,J>

Type Parameters:

T - the PDO type holding the relation to the joined PDO

J - the joined PDO type

public class Join<T extends PersistentDomainObject<T>,J extends PersistentDomainObject<J>>
extends Object

PDO join.

Joins two PDOs within the same select.
Used by eager joins and explicit domain-driven joins.
Works for composite and non-composite relations.

Author:

harald

Constructor Summary

Constructors

Constructor and Description
Join(JoinType type, String columnName, String joinedColumnName, Class<J> joinedClass, String joinAlias, BiConsumer<T,J> joiner) Creates a join.

Method Summary

Modifier and Type	Method and Description
J	createJoinedPdo(T pdo) Creates a new PDO to join to given pdo.
String	getColumnName() Gets the column name of the PDO.
String	getJoinAlias() Gets the alias of the joined PDO.
Class<J>	getJoinedClass() Gets the joined PDO class.
String	getJoinedColumnName() Gets the joined column name.
BiConsumer<T,J>	getJoiner() Gets the joiner.
J	getLastJoinedPdo() Gets the last PDO joined to the last PDO.
JoinType	getType() Gets the join type.
void	initialize() Initializes the join.
boolean	isExplicitIdAliasRequired() Returne whether an extra ID-alias must be added to the joined select statement.
boolean	isListJoin() Returns whether joined to list or object.
void	join(T pdo, J pdoToJoin) Joins a pdo with another pdo. The last joined pdo is remembered and can be retrieved via getLastJoinedPdo().

Methods inherited from class java.lang.Object

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

Constructor Detail

Join

public Join(JoinType type,
            String columnName,
            String joinedColumnName,
            Class<J> joinedClass,
            String joinAlias,
            BiConsumer<T,J> joiner)

Creates a join.

Parameters:

type - the join type

columnName - the column name of the PDO (includung table alias!)

joinedColumnName - the column name of the joined PDO (includung table alias!)

joinedClass - the joined class

joinAlias - the alias of the joined pdo

joiner - the joiner

Method Detail

getType

public JoinType getType()

Gets the join type.

Returns:

the type

isListJoin

public boolean isListJoin()

Returns whether joined to list or object.

Returns:

true if to list

isExplicitIdAliasRequired

public boolean isExplicitIdAliasRequired()

Returne whether an extra ID-alias must be added to the joined select statement. This is true for multi-table inherited object relations.

Returns:

true if ID alias necessary

getColumnName

public String getColumnName()

Gets the column name of the PDO.

Returns:

the column name

getJoinedColumnName

public String getJoinedColumnName()

Gets the joined column name.

Returns:

the column name, "id" if object join, else list join

getJoinedClass

public Class<J> getJoinedClass()

Gets the joined PDO class.

Returns:

the class

getJoinAlias

public String getJoinAlias()

Gets the alias of the joined PDO.

Returns:

the alias

getJoiner

public BiConsumer<T,J> getJoiner()

Gets the joiner.

Returns:

the joiner

initialize

public void initialize()

Initializes the join.

createJoinedPdo

public J createJoinedPdo(T pdo)

Creates a new PDO to join to given pdo.

Parameters:

pdo - the pdo to join to

Returns:

the pdo to join

join

public void join(T pdo,
                 J pdoToJoin)

Joins a pdo with another pdo.
The last joined pdo is remembered and can be retrieved via getLastJoinedPdo().

Parameters:

pdo - the pdo, null if none

pdoToJoin - the pdo to join, null to finish the joining process

getLastJoinedPdo

public J getLastJoinedPdo()

Gets the last PDO joined to the last PDO.

Returns:

the last joined PDO, null if nothing joined so far