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

All Implemented Interfaces:

Serializable
```
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

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class ForeignKey.FKMapKey

Field Summary

Fields
Modifier and Type	Field	Description
`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

Constructors
Constructor	Description
`ForeignKey()`	Default constructor.
`ForeignKey(String name, Table table)`	Deprecated.
`ForeignKey(DBIdentifier name, Table table)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`void`	`addColumn(ForeignKey fk)`	Joins the column of a single column FK to this FK.
`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`	`equals(Object o)`
`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.
`DBIdentifier`	`getPrimaryKeyColumnIdentifier()`
`String`	`getPrimaryKeyColumnName()`	Deprecated.
`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()`.
`DBIdentifier`	`getPrimaryKeySchemaIdentifier()`
`String`	`getPrimaryKeySchemaName()`	Deprecated.
`Table`	`getPrimaryKeyTable()`	Returns the table this foreign key is linking to, if it is known yet.
`DBIdentifier`	`getPrimaryKeyTableIdentifier()`
`String`	`getPrimaryKeyTableName()`	Deprecated.
`int`	`getRefCount()`
`int`	`getUpdateAction()`	Return the update action for the key.
`int`	`hashCode()`
`boolean`	`hasNotNullColumns()`	Checks for non-nullable local columns.
`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(Object val, Column toPK)`	Join a constant value 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.
`DBIdentifier`	`loadIdentifierFromDB(DBDictionary dbdict, Connection conn)`
`String`	`loadNameFromDB(DBDictionary dbdict, Connection conn)`	Deprecated.
`void`	`ref()`
`void`	`refColumns()`	Ref all columns in this key.
`boolean`	`removeJoin(Column col)`	Remove any joins inolving the given column.
`void`	`setConstantJoins(Object[] consts, Column[] pkCols)`	Set the foreign key's constant joins.
`void`	`setConstantJoins(Column[] cols, Object[] consts)`	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`	`setPrimaryKeyColumnIdentifier(DBIdentifier pkColumnName)`
`void`	`setPrimaryKeyColumnName(String pkColumnName)`	Deprecated.
`void`	`setPrimaryKeySchemaIdentifier(DBIdentifier pkSchemaName)`
`void`	`setPrimaryKeySchemaName(String pkSchemaName)`	Deprecated.
`void`	`setPrimaryKeyTableIdentifier(DBIdentifier pkTableName)`
`void`	`setPrimaryKeyTableName(String pkTableName)`	Deprecated.
`void`	`setUpdateAction(int action)`	Set the update action for the key.

Methods inherited from class org.apache.openjpa.jdbc.schema.Constraint
getColumnIdentifier, getColumnName, getFullIdentifier, getFullName, getIdentifier, getName, getQualifiedPath, getSchemaIdentifier, getSchemaName, getTable, getTableIdentifier, getTableName, isDeferred, setColumnIdentifier, setColumnName, setDeferred, setIdentifier, setName, setSchemaIdentifier, setSchemaName, setTableIdentifier, setTableName, toString

Methods inherited from class java.lang.Object
clone, finalize, getClass, 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
- Constructor Detail
  - ForeignKey
```
public ForeignKey()
```
    Default constructor.
  - ForeignKey
```
@Deprecated
public ForeignKey(String name,
                  Table table)
```
    Deprecated.
    
    Constructor.
    
    Parameters:
    
    name - the foreign key name, if any
    
    table - the local table of the foreign key
  - ForeignKey
```
public ForeignKey(DBIdentifier name,
                  Table table)
```
- 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
```
@Deprecated
public String getPrimaryKeyTableName()
```
    Deprecated.
    
    The name of the primary key table.
  - getPrimaryKeyTableIdentifier
```
public DBIdentifier getPrimaryKeyTableIdentifier()
```
  - setPrimaryKeyTableName
```
@Deprecated
public void setPrimaryKeyTableName(String pkTableName)
```
    Deprecated.
    
    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.
  - setPrimaryKeyTableIdentifier
```
public void setPrimaryKeyTableIdentifier(DBIdentifier pkTableName)
```
  - getPrimaryKeySchemaName
```
@Deprecated
public String getPrimaryKeySchemaName()
```
    Deprecated.
    
    The name of the primary key table's schema.
  - getPrimaryKeySchemaIdentifier
```
public DBIdentifier getPrimaryKeySchemaIdentifier()
```
  - setPrimaryKeySchemaName
```
@Deprecated
public void setPrimaryKeySchemaName(String pkSchemaName)
```
    Deprecated.
    
    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.
  - setPrimaryKeySchemaIdentifier
```
public void setPrimaryKeySchemaIdentifier(DBIdentifier pkSchemaName)
```
  - getPrimaryKeyColumnName
```
@Deprecated
public String getPrimaryKeyColumnName()
```
    Deprecated.
    
    The name of the primary key column.
  - getPrimaryKeyColumnIdentifier
```
public DBIdentifier getPrimaryKeyColumnIdentifier()
```
  - setPrimaryKeyColumnName
```
@Deprecated
public void setPrimaryKeyColumnName(String pkColumnName)
```
    Deprecated.
    
    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.
  - setPrimaryKeyColumnIdentifier
```
public void setPrimaryKeyColumnIdentifier(DBIdentifier pkColumnName)
```
  - 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.
  - hasNotNullColumns
```
public boolean hasNotNullColumns()
```
    Checks for non-nullable local columns.
  - loadNameFromDB
```
@Deprecated
public String loadNameFromDB(DBDictionary dbdict,
                             Connection conn)
```
    Deprecated.
    
    Return the name of the foreignkey constraint as defined in the database.
  - loadIdentifierFromDB
```
public DBIdentifier loadIdentifierFromDB(DBDictionary dbdict,
                                         Connection conn)
```
  - addColumn
```
public void addColumn(ForeignKey fk)
```
    Joins the column of a single column FK to this FK.
    
    Parameters:
    
    fk -
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Constraint
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Constraint
  - getRefCount
```
public int getRefCount()
```
  - ref
```
public void ref()
```
  - deref
```
public void deref()
```

Class ForeignKey

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

ACTION_NONE

ACTION_RESTRICT

ACTION_CASCADE

ACTION_NULL

ACTION_DEFAULT

Constructor Detail

ForeignKey

ForeignKey

ForeignKey

Method Detail

getAction

getActionName

isLogical

isPrimaryKeyAutoAssigned

getPrimaryKeyTableName

getPrimaryKeyTableIdentifier

setPrimaryKeyTableName

setPrimaryKeyTableIdentifier

getPrimaryKeySchemaName

getPrimaryKeySchemaIdentifier

setPrimaryKeySchemaName

setPrimaryKeySchemaIdentifier

getPrimaryKeyColumnName

getPrimaryKeyColumnIdentifier

setPrimaryKeyColumnName

setPrimaryKeyColumnIdentifier

getKeySequence

setKeySequence

getDeleteAction

setDeleteAction

getUpdateAction

setUpdateAction

getIndex

getPrimaryKeyColumn

getColumn

getConstant

getPrimaryKeyConstant

getColumns

getConstants

getPrimaryKeyConstants

containsColumn

containsPrimaryKeyColumn

containsConstantColumn

containsConstantPrimaryKeyColumn

getPrimaryKeyColumns

getConstantColumns

getConstantPrimaryKeyColumns

setJoins

setConstantJoins

setConstantJoins

join

joinConstant

joinConstant

removeJoin

getPrimaryKeyTable

refColumns

derefColumns

equalsForeignKey

columnsMatch

hasNotNullColumns

loadNameFromDB

loadIdentifierFromDB

addColumn

equals

hashCode

getRefCount

ref

deref