org.liquidsite.core.data
Class AbstractPeer

java.lang.Object
  org.liquidsite.core.data.AbstractPeer

Direct Known Subclasses:

AttributePeer, ConfigurationPeer, ContentPeer, DomainPeer, GroupPeer, HostPeer, LockPeer, PermissionPeer, PreferencePeer, UserGroupPeer, UserPeer

public abstract class AbstractPeer

extends java.lang.Object

An abstract data object peer. This class provides some of the functionality needed by all data object peers. The data object peers each provide specialized static methods for operating on the data objects by retrieving and storing them to the data source (i.e. a database).

Constructor Summary

protected

AbstractPeer(java.lang.String name) Creates a new peer for the specified database object.

Method Summary

protected long	count(DataSource src, DatabaseQuery query) Performs a database query that returns a single number as the result.
protected void	delete(DataSource src, DatabaseQuery query) Performs a database delete statement.
protected abstract AbstractData	getDataObject() Returns a new instance of the data object.
protected void	insert(DataSource src, DatabaseQuery query) Performs a database insert statement.
protected AbstractData	select(DataSource src, DatabaseQuery query) Performs a database select query.
protected java.util.ArrayList	selectList(DataSource src, DatabaseQuery query) Performs a database list select query.
protected void	update(DataSource src, DatabaseQuery query) Performs a database update statement.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractPeer

protected AbstractPeer(java.lang.String name)

Creates a new peer for the specified database object.

Parameters:

name - the database object name

Method Detail

getDataObject

protected abstract AbstractData getDataObject()

Returns a new instance of the data object.

Returns:

a new instance of the data object

count

protected long count(DataSource src,
                     DatabaseQuery query)
              throws DataObjectException

Performs a database query that returns a single number as the result. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Returns:

the query result number, or zero (0) if no results were found

Throws:

DataObjectException - if the query couldn't be executed correctly, or the results were malformed

select

protected AbstractData select(DataSource src,
                              DatabaseQuery query)
                       throws DataObjectException

Performs a database select query. This query is supposed to return either one or zero rows. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Returns:

the database object found, or null if the query didn't match any row

Throws:

DataObjectException - if the query couldn't be executed correctly, or the results were malformed

selectList

protected java.util.ArrayList selectList(DataSource src,
                                         DatabaseQuery query)
                                  throws DataObjectException

Performs a database list select query. This query is supposed to zero or more rows. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Returns:

the list of database objects found

Throws:

DataObjectException - if the query couldn't be executed correctly, or the results were malformed

insert

protected void insert(DataSource src,
                      DatabaseQuery query)
               throws DataObjectException

Performs a database insert statement. No database results are returned. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Throws:

DataObjectException - if the statement couldn't be executed correctly

update

protected void update(DataSource src,
                      DatabaseQuery query)
               throws DataObjectException

Performs a database update statement. No database results are returned. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Throws:

DataObjectException - if the statement couldn't be executed correctly

delete

protected void delete(DataSource src,
                      DatabaseQuery query)
               throws DataObjectException

Performs a database delete statement. No database results are returned. The data source will NOT be closed after this operation.

Parameters:

src - the data source to use

query - the database query

Throws:

DataObjectException - if the statement couldn't be executed correctly