org.datanucleus.metadata

Class ForeignKeyMetaData

java.lang.Object

org.datanucleus.metadata.MetaData

org.datanucleus.metadata.ConstraintMetaData

org.datanucleus.metadata.ForeignKeyMetaData

All Implemented Interfaces:

Serializable

public class ForeignKeyMetaData
extends ConstraintMetaData

Foreign keys in metadata serve two quite different purposes. First, when generating schema, the foreign key element identifies foreign keys to be generated. Second, when using the database, foreign key elements identify foreign keys that are assumed to exist in the database. This is important for the runtime to properly order insert, update, and delete statements to avoid constraint violations. A foreign-key element can be contained by a field, element, key, value, or join element, if all of the columns mapped are to be part of the same foreign key. A foreign-key element can be contained within a class element. In this case, the column elements are mapped elsewhere, and the column elements contained in the foreign-key element have only the column name.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected List<ColumnMetaData>	columns The columns for this foreign key.
protected boolean	deferred The deferred attribute specifies whether the foreign key constraint is defined to be checked only at commit time.
protected ForeignKeyAction	deleteAction Foreign keys represent a consistency constraint in the database that must be maintained.
protected String	fkDefinition Alternative method of specifying FK where we just supply the string defining it (JPA crap).
protected boolean	fkDefinitionApplies
protected boolean	unique The unique attribute specifies whether the foreign key constraint is defined to be a unique constraint as well.
protected ForeignKeyAction	updateAction Foreign keys represent a consistency constraint in the database that must be maintained.

Fields inherited from class org.datanucleus.metadata.ConstraintMetaData

columnNames, memberNames, name, table

Fields inherited from class org.datanucleus.metadata.MetaData

EXTENSION_CLASS_MULTITENANCY_COLUMN_LENGTH, EXTENSION_CLASS_MULTITENANCY_COLUMN_NAME, EXTENSION_CLASS_MULTITENANCY_DISABLE, EXTENSION_CLASS_MULTITENANCY_JDBC_TYPE, EXTENSION_CLASS_READ_ONLY, EXTENSION_CLASS_VERSION_FIELD_NAME, EXTENSION_CLASS_VIEW_DEFINITION, EXTENSION_CLASS_VIEW_IMPORTS, EXTENSION_MEMBER_CACHEABLE, EXTENSION_MEMBER_CALENDAR_ONE_COLUMN, EXTENSION_MEMBER_CASCADE_PERSIST, EXTENSION_MEMBER_CASCADE_REFRESH, EXTENSION_MEMBER_CASCADE_UPDATE, EXTENSION_MEMBER_COMPARATOR_NAME, EXTENSION_MEMBER_CONTAINER_ALLOW_NULLS, EXTENSION_MEMBER_ENUM_GETTER_BY_VALUE, EXTENSION_MEMBER_ENUM_VALUE_GETTER, EXTENSION_MEMBER_FETCH_FK_ONLY, EXTENSION_MEMBER_IMPLEMENTATION_CLASSES, EXTENSION_MEMBER_INSERTABLE, EXTENSION_MEMBER_LIST_ORDERING, EXTENSION_MEMBER_RELATION_DISCRIM_COLUMN, EXTENSION_MEMBER_RELATION_DISCRIM_PK, EXTENSION_MEMBER_RELATION_DISCRIM_VALUE, EXTENSION_MEMBER_STRATEGY_WHEN_NOTNULL, EXTENSION_MEMBER_TYPE_CONVERTER_DISABLED, EXTENSION_MEMBER_TYPE_CONVERTER_NAME, EXTENSION_MEMBER_UPDATEABLE, extensions, METADATA_CREATED_STATE, METADATA_INITIALISED_STATE, METADATA_POPULATED_STATE, METADATA_USED_STATE, metaDataState, parent, VENDOR_NAME

Constructor Summary

Constructors

Constructor and Description
ForeignKeyMetaData()
ForeignKeyMetaData(ForeignKeyMetaData fkmd) Copy constructor.

Method Summary

Modifier and Type	Method and Description
void	addColumn(ColumnMetaData colmd)
ColumnMetaData[]	getColumnMetaData()
ForeignKeyAction	getDeleteAction()
String	getFkDefinition()
boolean	getFkDefinitionApplies()
ForeignKeyAction	getUpdateAction()
boolean	isDeferred()
boolean	isUnique()
ColumnMetaData	newColumnMetaData() Method to create a new column, add it, and return it.
ForeignKeyMetaData	setDeferred(boolean deferred)
ForeignKeyMetaData	setDeferred(String deferred)
void	setDeleteAction(ForeignKeyAction deleteAction)
void	setFkDefinition(String def)
void	setFkDefinitionApplies(boolean flag)
ForeignKeyMetaData	setUnique(boolean unique)
ForeignKeyMetaData	setUnique(String unique)
ForeignKeyMetaData	setUpdateAction(ForeignKeyAction updateAction)

Methods inherited from class org.datanucleus.metadata.ConstraintMetaData

addColumn, addMember, getColumnNames, getMemberNames, getName, getNumberOfColumns, getNumberOfMembers, getTable, setName, setTable

Methods inherited from class org.datanucleus.metadata.MetaData

addExtension, addExtensions, getExtensions, getMetaDataManager, getNoOfExtensions, getParent, getValueForExtension, getValuesForExtension, hasExtension, initialise, isInitialised, isPopulated, isUsed, removeExtension, setExtensions, setParent

Methods inherited from class java.lang.Object

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

Field Detail

columns

protected List<ColumnMetaData> columns

The columns for this foreign key. Note that we don't use the "columnNames" in the superclass since the user can define the column target name also for a foreign-key.

unique

protected boolean unique

The unique attribute specifies whether the foreign key constraint is defined to be a unique constraint as well. This is most often used with one-to-one mappings.

deferred

protected boolean deferred

The deferred attribute specifies whether the foreign key constraint is defined to be checked only at commit time.

deleteAction

protected ForeignKeyAction deleteAction

Foreign keys represent a consistency constraint in the database that must be maintained. The user can specify by the value of the delete-action attribute what happens if the target row of a foreign key is deleted.

updateAction

protected ForeignKeyAction updateAction

Foreign keys represent a consistency constraint in the database that must be maintained. The user can specify by the update-action attribute what happens if the target row of a foreign key is updated.

fkDefinition

protected String fkDefinition

Alternative method of specifying FK where we just supply the string defining it (JPA crap).

fkDefinitionApplies

protected boolean fkDefinitionApplies

Constructor Detail

ForeignKeyMetaData

public ForeignKeyMetaData()

ForeignKeyMetaData

public ForeignKeyMetaData(ForeignKeyMetaData fkmd)

Copy constructor.

Parameters:

fkmd - The metadata to copy

Method Detail

addColumn

public void addColumn(ColumnMetaData colmd)

newColumnMetaData

public ColumnMetaData newColumnMetaData()

Method to create a new column, add it, and return it.

Returns:

The column metadata

getColumnMetaData

public final ColumnMetaData[] getColumnMetaData()

isDeferred

public final boolean isDeferred()

setDeferred

public ForeignKeyMetaData setDeferred(boolean deferred)

setDeferred

public ForeignKeyMetaData setDeferred(String deferred)

getDeleteAction

public final ForeignKeyAction getDeleteAction()

setDeleteAction

public void setDeleteAction(ForeignKeyAction deleteAction)

isUnique

public final boolean isUnique()

setUnique

public ForeignKeyMetaData setUnique(boolean unique)

setUnique

public ForeignKeyMetaData setUnique(String unique)

getUpdateAction

public final ForeignKeyAction getUpdateAction()

setUpdateAction

public ForeignKeyMetaData setUpdateAction(ForeignKeyAction updateAction)

setFkDefinition

public void setFkDefinition(String def)

getFkDefinition

public String getFkDefinition()

setFkDefinitionApplies

public void setFkDefinitionApplies(boolean flag)

getFkDefinitionApplies

public boolean getFkDefinitionApplies()