com.objectwave.persist.broker
Class TableSequence

java.lang.Object
  |
  +--com.objectwave.persist.broker.TableSequence

All Implemented Interfaces:

PrimaryKeyStrategy

public class TableSequence

extends java.lang.Object

implements PrimaryKeyStrategy

This PrimaryKeyStrategy involves selecting a sequence value from a table. The column name selected is constructed with the following format {0}_uid_seq, where {0} is the table name of the persistent object that requires a PK.

Version:

$Id: TableSequence.java,v 2.1 2001/10/03 14:59:03 dave_hoag Exp $

Author:

Trever M. Shick with help from dhoag

Field Summary

protected java.lang.String	sequenceColumnSuffix
protected java.lang.String	sequenceTableName

Constructor Summary

TableSequence()

Method Summary

java.lang.String	getSequenceColumnSuffix() Returns the suffix of the column which is queried to get the next sequence number for a given table.
java.lang.String	getSequenceTableName() Returns the name of the table which is queried to get the next sequence number for a given table.
java.lang.Object	nextPrimaryKey(RDBBroker broker, RDBPersistence pObj) Calls to this method should never return the same value.
void	setSequenceColumnSuffix(java.lang.String newSuffix) Bean style mutator to allow client code to alter which column that the sequence value is selected from.
void	setSequenceTableName(java.lang.String newTableName) Bean style mutator to allow client code to alter which table that the sequence value is selected from.

Methods inherited from class java.lang.Object

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

Field Detail

sequenceTableName

protected java.lang.String sequenceTableName

sequenceColumnSuffix

protected java.lang.String sequenceColumnSuffix

Constructor Detail

TableSequence

public TableSequence()

Method Detail

setSequenceTableName

public void setSequenceTableName(java.lang.String newTableName)

Bean style mutator to allow client code to alter which table that the sequence value is selected from. If newTableName is null or a 0 length string, the parameter is ignored and the value is not changed.

Parameters:

newTableName - The new table name from which to select the sequence value from.

setSequenceColumnSuffix

public void setSequenceColumnSuffix(java.lang.String newSuffix)

Bean style mutator to allow client code to alter which column that the sequence value is selected from. If newColumnName is null or a 0 length string, the parameter is ignored and the value is not changed.

Parameters:

newSuffix - The new SequenceColumnSuffix value

getSequenceTableName

public java.lang.String getSequenceTableName()

Returns the name of the table which is queried to get the next sequence number for a given table. With Oracle, this is generally "DUAL" since sequence values are often accessed via performing : SELECT my_seq.nextval FROM DUAL;

Returns:

The name of the table from which a sequence value is selected.

getSequenceColumnSuffix

public java.lang.String getSequenceColumnSuffix()

Returns the suffix of the column which is queried to get the next sequence number for a given table. With Oracle, this is generally "_uid_seq.NEXTVAL" since sequence values are often accessed via performing : SELECT my_uid_seq.nextval FROM DUAL; "my" is the table name of the persistent object for which a sequence is being gathered.

Returns:

The name of the table from which a sequence value is selected.

nextPrimaryKey

public java.lang.Object nextPrimaryKey(RDBBroker broker,
                                       RDBPersistence pObj)
                                throws java.sql.SQLException,
                                       QueryException

Description copied from interface: PrimaryKeyStrategy

Calls to this method should never return the same value. When this method is called, the broker assumes the value returned will create a unique primary key value that can identify a unique row in the database.

Specified by:

nextPrimaryKey in interface PrimaryKeyStrategy

Parameters:

broker - - The current broker being used.

pObj - - The peristent object to get a primary key for

Returns:

an object that represents the next primary key value for the given persistent object pObj

Throws:

java.sql.SQLException

QueryException