org.brains2b.data
Interface DataControl

All Known Implementing Classes:

OracleDC

public interface DataControl

Interface DataControl

Used to implement DataControl for Data objects

Implementation has the specific information on how to write/read data with a data source to a data store. The DataControl is used from a class which implements DataController which takes the data object as parameter and has some mechanisme to find the DataControl implementation belonging to the DataObject.

You would not refer to a DataControl directly in you code. You would just get and set the data object to the general DataController and leave it to the DataController to invoke the DataControl and handle the read/write of the data.

This interface is defined in general terms because no assumptions should be made about the type of datastore. The most simple implementation would be using a JDBC connection, but you could also use it for XML or flat file datastorage

Classes which implement this interface can be generated by Sql2Class project TODO make a link to the Sql2Class

Version:

0.10 [30-12-2001]

Author:

dennis@brains2b.nl

Method Summary

int	deleteOnPk() Delete the data object from the datatore on primary key.
int	insert() insert a data object
java.util.Vector	selectAll() select all Records for de data object this data controller was created for
java.util.Vector	selectFromCondition(Condition con) select all records meeting the values set in Condition.
java.util.Vector	selectOnParent(java.lang.Object o) selects a collection of Objects which have a relation to a parent given by Object o
java.lang.Object	selectOnPk(java.lang.Object o) selects a data object on the basis of the primary key contained in Object o
int	updateOnPk() Update the data object on primary key.

Method Detail

updateOnPk

public int updateOnPk()
               throws java.lang.Exception

Update the data object on primary key.

Returns:

int, the number of records updated, should alwyas return one

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

insert

public int insert()
           throws java.lang.Exception

insert a data object

Returns:

int, the number or records updated, should always return one

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

deleteOnPk

public int deleteOnPk()
               throws java.lang.Exception

Delete the data object from the datatore on primary key.

Returns:

int, the number or records deleted, should always return one

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

selectOnParent

public java.util.Vector selectOnParent(java.lang.Object o)
                                throws java.lang.Exception

selects a collection of Objects which have a relation to a parent given by Object o

This method should always be implemented manually while the relation cannot be determined automatically.

Parameters:

o - Object, an Object representing the parent

Returns:

Vector a collection of Objects for which this DataControl was created.

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

selectOnPk

public java.lang.Object selectOnPk(java.lang.Object o)
                            throws java.lang.Exception

selects a data object on the basis of the primary key contained in Object o

Keep in mind that a selectOnPk(Object) expects an instance of the Object you're retrieving and returning an Object you're retrieving which could only match on the primary key

Parameters:

o - Object, a data object which contains the primary key to retrieve the dataobject.

Returns:

Object, the data object which is retrieved from the primary key.

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

selectAll

public java.util.Vector selectAll()
                           throws java.lang.Exception

select all Records for de data object this data controller was created for

Returns:

Vector, a collection of data objects

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

selectFromCondition

public java.util.Vector selectFromCondition(Condition con)
                                     throws java.lang.Exception

select all records meeting the values set in Condition. The order would be the same as defined by the order by clause in the Condition

Parameters:

con - Condition, the condition to be used to retrieve the collection of data objects

Returns:

Vector, a collection of data objects

Throws:

Exception, - exception thrown from the specific data store controls, such as a JDBC driver

java.lang.Exception

See Also:

Condition