org.apache.openjpa.jdbc.schema
Class ForeignKey

java.lang.Object
  org.apache.openjpa.jdbc.schema.Constraint
      org.apache.openjpa.jdbc.schema.ForeignKey

public class ForeignKey
extends Constraint

Represents a database foreign key; may be a logical key with no database representation. This class can also represent a partial key, aligning with DatabaseMetaData.

Author:

Abe White

Field Summary

LinkedMap	_constsPK
static int	ACTION_CASCADE Cascade any modification of the joined primary key columns to this table.
static int	ACTION_DEFAULT Set the local columns to their default values if the primary key columns are modified.
static int	ACTION_NONE Logical foreign key; links columns, but does not perform any action when the joined primary key columns are modified.
static int	ACTION_NULL Null the local columns if the joined primary key columns are modified.
static int	ACTION_RESTRICT Throw an exception if joined primary key columns are modified.

Constructor Summary

ForeignKey()
Default constructor.

ForeignKey(String name, Table table)
Constructor.

Method Summary

boolean	columnsMatch(Column[] fkCols, Column[] fkPKCols) Return true if the given local and foreign columns match those on this key.
boolean	containsColumn(Column col) Return true if the fk includes the given local column.
boolean	containsConstantColumn(Column col) Return true if the fk includes the given local column.
boolean	containsConstantPrimaryKeyColumn(Column col) Return true if the fk includes the given primary key column.
boolean	containsPrimaryKeyColumn(Column col) Return true if the fk includes the given primary key column.
void	deref()
void	derefColumns() Deref all columns in this key.
boolean	equalsForeignKey(ForeignKey fk) Foreign keys are equal if the satisfy the equality constraints of Constraint and they have the same local and primary key columns and action.
static int	getAction(String name) Return the foreign key action constant for the given action name.
static String	getActionName(int action) Return the foreign key action name for the given action constant.
Column	getColumn(Column pk) Return the local column joined to the given primary key column.
Column[]	getColumns() Return the local columns in the foreign key local table order.
Object	getConstant(Column local) Return the constant value assigned to the given local column.
Column[]	getConstantColumns() Return the local columns that we link to using constant values.
Column[]	getConstantPrimaryKeyColumns() Return the primary key columns that we link to using constant values.
Object[]	getConstants() Return the constant values assigned to the local columns returned by getConstantColumns().
int	getDeleteAction() Return the delete action for the key.
int	getIndex() Return the foreign key's 0-based index in the owning table.
int	getKeySequence() The sequence of this join in the foreign key.
Column	getPrimaryKeyColumn(Column local) Return the primary key column joined to the given local column.
String	getPrimaryKeyColumnName() The name of the primary key column.
Column[]	getPrimaryKeyColumns() Return the foreign columns in the foreign key, in join-order with the result of getColumns().
Object	getPrimaryKeyConstant(Column pk) Return the constant value assigned to the given primary key column.
Object[]	getPrimaryKeyConstants() Return the constant values assigned to the primary key columns returned by getConstantPrimaryKeyColumns().
String	getPrimaryKeySchemaName() The name of the primary key table's schema.
Table	getPrimaryKeyTable() Returns the table this foreign key is linking to, if it is known yet.
String	getPrimaryKeyTableName() The name of the primary key table.
int	getRefCount()
int	getUpdateAction() Return the update action for the key.
boolean	isLogical() Return whether this constraint is a logical constraint only; i.e.
boolean	isPrimaryKeyAutoAssigned() Whether the primary key columns of this key are auto-incrementing, or whether they themselves are members of a foreign key who's primary key is auto-incrementing (recursing to arbitrary depth).
void	join(Column local, Column toPK) Join a local column to a primary key column of another table.
void	joinConstant(Column col, Object val) Join a constant value to a local column of this table.
void	joinConstant(Object val, Column toPK) Join a constant value to a primary key column of another table.
void	ref()
void	refColumns() Ref all columns in this key.
boolean	removeJoin(Column col) Remove any joins inolving the given column.
void	setConstantJoins(Column[] cols, Object[] consts) Set the foreign key's constant joins.
void	setConstantJoins(Object[] consts, Column[] pkCols) Set the foreign key's constant joins.
void	setDeleteAction(int action) Set the delete action for the key.
void	setJoins(Column[] cols, Column[] pkCols) Set the foreign key's joins.
void	setKeySequence(int seq) The sequence of this join in the foreign key.
void	setPrimaryKeyColumnName(String pkColumnName) The name of the primary key column.
void	setPrimaryKeySchemaName(String pkSchemaName) The name of the primary key table's schema.
void	setPrimaryKeyTableName(String pkTableName) The name of the primary key table.
void	setUpdateAction(int action) Set the update action for the key.

Methods inherited from class org.apache.openjpa.jdbc.schema.Constraint

getColumnName, getFullName, getName, getSchemaName, getTable, getTableName, isDeferred, setColumnName, setDeferred, setName, setSchemaName, setTableName, toString

Methods inherited from class java.lang.Object

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

Field Detail

ACTION_NONE

public static final int ACTION_NONE

Logical foreign key; links columns, but does not perform any action when the joined primary key columns are modified.

See Also:

Constant Field Values

ACTION_RESTRICT

public static final int ACTION_RESTRICT

Throw an exception if joined primary key columns are modified.

See Also:

Constant Field Values

ACTION_CASCADE

public static final int ACTION_CASCADE

Cascade any modification of the joined primary key columns to this table. If the joined primary key row is deleted, the row in this table will also be deleted.

See Also:

Constant Field Values

ACTION_NULL

public static final int ACTION_NULL

Null the local columns if the joined primary key columns are modified.

See Also:

Constant Field Values

ACTION_DEFAULT

public static final int ACTION_DEFAULT

Set the local columns to their default values if the primary key columns are modified.

See Also:

Constant Field Values

_constsPK

public LinkedMap _constsPK

Constructor Detail

ForeignKey

public ForeignKey()

Default constructor.

ForeignKey

public ForeignKey(String name,
                  Table table)

Constructor.

Parameters:

name - the foreign key name, if any

table - the local table of the foreign key

Method Detail

getAction

public static int getAction(String name)

Return the foreign key action constant for the given action name.

getActionName

public static String getActionName(int action)

Return the foreign key action name for the given action constant.

isLogical

public boolean isLogical()

Description copied from class: Constraint

Return whether this constraint is a logical constraint only; i.e. if it does not exist in the database.

Specified by:

isLogical in class Constraint

isPrimaryKeyAutoAssigned

public boolean isPrimaryKeyAutoAssigned()

Whether the primary key columns of this key are auto-incrementing, or whether they themselves are members of a foreign key who's primary key is auto-incrementing (recursing to arbitrary depth).

getPrimaryKeyTableName

public String getPrimaryKeyTableName()

The name of the primary key table.

setPrimaryKeyTableName

public void setPrimaryKeyTableName(String pkTableName)

The name of the primary key table. You can only set the primary key table name on foreign keys that have not already been joined.

getPrimaryKeySchemaName

public String getPrimaryKeySchemaName()

The name of the primary key table's schema.

setPrimaryKeySchemaName

public void setPrimaryKeySchemaName(String pkSchemaName)

The name of the primary key table's schema. You can only set the primary key schema name on foreign keys that have not already been joined.

getPrimaryKeyColumnName

public String getPrimaryKeyColumnName()

The name of the primary key column.

setPrimaryKeyColumnName

public void setPrimaryKeyColumnName(String pkColumnName)

The name of the primary key column. You can only set the primary key column name on foreign keys that have not already been joined.

getKeySequence

public int getKeySequence()

The sequence of this join in the foreign key.

setKeySequence

public void setKeySequence(int seq)

The sequence of this join in the foreign key.

getDeleteAction

public int getDeleteAction()

Return the delete action for the key. Will be one of: ACTION_NONE, ACTION_RESTRICT, ACTION_CASCADE, ACTION_NULL, ACTION_DEFAULT.

setDeleteAction

public void setDeleteAction(int action)

Set the delete action for the key. Must be one of: ACTION_NONE, ACTION_RESTRICT, ACTION_CASCADE, ACTION_NULL, ACTION_DEFAULT.

getUpdateAction

public int getUpdateAction()

Return the update action for the key. Will be one of: ACTION_NONE, ACTION_RESTRICT, ACTION_CASCADE, ACTION_NULL, ACTION_DEFAULT.

setUpdateAction

public void setUpdateAction(int action)

Set the update action for the key. Must be one of: ACTION_NONE, ACTION_RESTRICT, ACTION_CASCADE, ACTION_NULL, ACTION_DEFAULT.

getIndex

public int getIndex()

Return the foreign key's 0-based index in the owning table.

getPrimaryKeyColumn

public Column getPrimaryKeyColumn(Column local)

Return the primary key column joined to the given local column.

getColumn

public Column getColumn(Column pk)

Return the local column joined to the given primary key column.

getConstant

public Object getConstant(Column local)

Return the constant value assigned to the given local column.

getPrimaryKeyConstant

public Object getPrimaryKeyConstant(Column pk)

Return the constant value assigned to the given primary key column.

getColumns

public Column[] getColumns()

Return the local columns in the foreign key local table order.

getConstants

public Object[] getConstants()

Return the constant values assigned to the local columns returned by getConstantColumns().

getPrimaryKeyConstants

public Object[] getPrimaryKeyConstants()

Return the constant values assigned to the primary key columns returned by getConstantPrimaryKeyColumns().

containsColumn

public boolean containsColumn(Column col)

Return true if the fk includes the given local column.

containsPrimaryKeyColumn

public boolean containsPrimaryKeyColumn(Column col)

Return true if the fk includes the given primary key column.

containsConstantColumn

public boolean containsConstantColumn(Column col)

Return true if the fk includes the given local column.

containsConstantPrimaryKeyColumn

public boolean containsConstantPrimaryKeyColumn(Column col)

Return true if the fk includes the given primary key column.

getPrimaryKeyColumns

public Column[] getPrimaryKeyColumns()

Return the foreign columns in the foreign key, in join-order with the result of getColumns().

getConstantColumns

public Column[] getConstantColumns()

Return the local columns that we link to using constant values.

getConstantPrimaryKeyColumns

public Column[] getConstantPrimaryKeyColumns()

Return the primary key columns that we link to using constant values.

setJoins

public void setJoins(Column[] cols,
                     Column[] pkCols)

Set the foreign key's joins.

setConstantJoins

public void setConstantJoins(Object[] consts,
                             Column[] pkCols)

Set the foreign key's constant joins.

setConstantJoins

public void setConstantJoins(Column[] cols,
                             Object[] consts)

Set the foreign key's constant joins.

join

public void join(Column local,
                 Column toPK)

Join a local column to a primary key column of another table.

joinConstant

public void joinConstant(Object val,
                         Column toPK)

Join a constant value to a primary key column of another table. The constant must be either a string or a number.

joinConstant

public void joinConstant(Column col,
                         Object val)

Join a constant value to a local column of this table. The constant must be either a string or a number.

removeJoin

public boolean removeJoin(Column col)

Remove any joins inolving the given column.

Returns:

true if the join was removed, false if not part of the key

getPrimaryKeyTable

public Table getPrimaryKeyTable()

Returns the table this foreign key is linking to, if it is known yet.

refColumns

public void refColumns()

Ref all columns in this key.

derefColumns

public void derefColumns()

Deref all columns in this key.

equalsForeignKey

public boolean equalsForeignKey(ForeignKey fk)

Foreign keys are equal if the satisfy the equality constraints of Constraint and they have the same local and primary key columns and action.

columnsMatch

public boolean columnsMatch(Column[] fkCols,
                            Column[] fkPKCols)

Return true if the given local and foreign columns match those on this key. This can be used to find foreign keys given only column linking information.

getRefCount

public int getRefCount()

ref

public void ref()

deref

public void deref()