org.brains2b.data

Interface DataController

All Known Subinterfaces:

TransactionController

public interface DataController

Interface for a general Controller to use for all different data objects.

Implementation of this class should be able to find the DataControl implementation for the type of Object which is provided as paramters through the methods

Implementations would look something like:

 
                public int update(Object o) throws Exception {
                        return findDc(Object o).update();
                }
 
                public DataControl findDc(Object o) throws Exception {
                        //some method to find and instantiate the DataControl
                }

 

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

Version:

0.20 [16-01-2008]

Author:

dennis@brains2b.nl

See Also:

DataControl

Method Summary

Modifier and Type	Method and Description
int	delete(java.lang.Object o) delete an object of type o from the datastore
int	insert(java.lang.Object o) insert an object of type o to the datastore
<T> T	retrieve(T o, Condition condition) retrieve an Object of the type of the Object o which match the supplied condition.
<T> java.util.List<T>	retrieveList(T o, Condition condition) retrieve a list of Objects of the type of the Object o which match the supplied condition.
int	update(java.lang.Object o) update an object of type o to the datastore

Method Detail

update

int update(java.lang.Object o)
    throws DataException

update an object of type o to the datastore

Parameters:

o - Object, the object to update

Returns:

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

Throws:

DataException - exception thrown if the specific data store controls throw an Exception, such as a JDBC driver.

See Also:

DataControl.update()

insert

int insert(java.lang.Object o)
    throws DataException

insert an object of type o to the datastore

Parameters:

o - Object, the object to insert

Returns:

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

Throws:

DataException - exception thrown if the specific data store controls throw an Exception, such as a JDBC driver.

See Also:

DataControl.insert()

delete

int delete(java.lang.Object o)
    throws DataException

delete an object of type o from the datastore

Parameters:

o - Object, the object to delete

Returns:

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

Throws:

DataException - exception thrown if the specific data store controls throw an Exception, such as a JDBC driver.

See Also:

DataControl.update()

retrieve

<T> T retrieve(T o,
               Condition condition)
        throws DataException

retrieve an Object of the type of the Object o which match the supplied condition.

Parameters:

o - Object the object which determines the type of objects you want to retrieve. An implementantion should not assume anything about the content of this Object and most implementations will ignore the values.

condition - Condition the condition which should be met by the retrieved objects

Returns:

An object which meets the condition. If more then one object meets the criteria implementations should only return the first one. Should return null if no object meets the condition.

Throws:

DataException - exception thrown if the specific data store controls throw an Exception, such as a JDBC driver.

See Also:

DataControl.retrieveList(Condition), Condition

retrieveList

<T> java.util.List<T> retrieveList(T o,
                                   Condition condition)
                            throws DataException

retrieve a list of Objects of the type of the Object o which match the supplied condition.

Parameters:

o - Object the object which determines the type of objects you want to retrieve. An implementantion should not assume anything about the content of this Object and most implementations will ignore the values.

condition - Condition the condition which should be met by the retrieved objects

Returns:

A list of Objects which meet the condition. Should return null if no object meets the condition.

Throws:

DataException - exception thrown if the specific data store controls throw an Exception, such as a JDBC driver.

See Also:

DataControl.retrieveList(Condition), Condition