org.apache.openjpa.jdbc.schema
Class Unique

java.lang.Object
  org.apache.openjpa.jdbc.schema.Constraint
      org.apache.openjpa.jdbc.schema.LocalConstraint
          org.apache.openjpa.jdbc.schema.Unique

All Implemented Interfaces:

Serializable

public class Unique
extends LocalConstraint

Represents a unique constraint. It can also represent a partial constraint.

Author:

Abe White, Pinaki Poddar

See Also:

Serialized Form

Constructor Summary

Unique()
Default constructor without a name.

Unique(String name, Table table)
Construct with given name.

Method Summary

void	addColumn(Column col) Adds the given column.
void	deref()
boolean	equalsUnique(Unique unq) Return true if the structure of this primary key matches that of the given one (same table, same columns).
String	getName() Gets the name of the constraint.
int	getRefCount()
boolean	isAutoNaming()
boolean	isLogical() Return whether this constraint is a logical constraint only; i.e.
void	ref()
void	setName(String name) Set the name of the constraint.

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

columnsMatch, containsColumn, derefColumns, equalsLocalConstraint, getColumns, refColumns, removeColumn, setColumns

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

Unique

public Unique()

Default constructor without a name. Implies that this constraint will auto-generate its name from the names of its columns, unless later the name is set explicitly.

Unique

public Unique(String name,
              Table table)

Construct with given name. Implies that this constraint will not auto-generate its name.

Parameters:

name - the name of the constraint, if any

table - the table of the constraint

Method Detail

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

addColumn

public void addColumn(Column col)

Adds the given column. The added column is set to non-nullable because a unique constraint on the database requires that its constituent columns are NOT NULL.

Overrides:

addColumn in class LocalConstraint

See Also:

Column.setNotNull(boolean)

setName

public void setName(String name)

Set the name of the constraint. This method cannot be called if the constraint already belongs to a table. Calling this method also has the side-effect of implying that the instance will not auto-generate its name.

Overrides:

setName in class Constraint

getName

public String getName()

Gets the name of the constraint. If no name has been set by the user then this method has the side-effect of auto-generating a name from the name of its columns.

Overrides:

getName in class Constraint

equalsUnique

public boolean equalsUnique(Unique unq)

Return true if the structure of this primary key matches that of the given one (same table, same columns).

isAutoNaming

public boolean isAutoNaming()

getRefCount

public int getRefCount()

ref

public void ref()

deref

public void deref()