com.cc.framework.ui.model.imp
Class KeyListDataModel

java.lang.Object
  com.cc.framework.ui.model.imp.KeyListDataModel

All Implemented Interfaces:

DataModel, ListDataModel, java.io.Serializable, VirtualDataModel

public abstract class KeyListDataModel

extends java.lang.Object

implements VirtualDataModel, ListDataModel, java.io.Serializable

ListDataModel which holds only a Key Set in Memory. The Display Beans are loaded as needed

Version:

$Revision: 1.10 $

Author:

Harald Schulz

See Also:

Serialized Form

Field Summary

private int	cache The List implements a very simple cache mechanism to prevent unnecessary loading
private java.lang.Object	cacheBean Cached row bean
private java.util.Vector	keySet The Set of Keys
private static long	serialVersionUID Serial Version UID

Constructor Summary

KeyListDataModel()

Method Summary

void	clear() Clears the current keyset
protected abstract java.util.Collection	doFetchKeys() Overwrite this method to load the keyset
protected abstract java.lang.Object	doFetchRowBean(java.lang.Object key) Overwrite this method to load one single row bean
protected void	doSetup() This method is called first to do any initialization processing
java.lang.Object	getElementAt(int index) Returns the (row) object for the specified index.
private java.lang.Object	getRowBean(int index) Returns the row bean for the given index
java.lang.String	getUniqueKey(int index) Returns a unique key for the row which is specified by the index.
void	setupKeys() Use this method to set up the keys collection explicit
int	size() Returns the number of rows within the list.

Methods inherited from class java.lang.Object

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

Field Detail

serialVersionUID

private static final long serialVersionUID

Serial Version UID

See Also:

Constant Field Values

keySet

private java.util.Vector keySet

The Set of Keys

cache

private int cache

The List implements a very simple cache mechanism to prevent unnecessary loading

cacheBean

private java.lang.Object cacheBean

Cached row bean

Constructor Detail

KeyListDataModel

public KeyListDataModel()

Method Detail

doSetup

protected void doSetup()
                throws java.lang.Exception

This method is called first to do any initialization processing

Throws:

java.lang.Exception - Will be thrown in case of an error in the integration layer

doFetchKeys

protected abstract java.util.Collection doFetchKeys()
                                             throws java.lang.Exception

Overwrite this method to load the keyset

Returns:

Collection of keys

Throws:

java.lang.Exception - An error ocurred while loading the keyset

doFetchRowBean

protected abstract java.lang.Object doFetchRowBean(java.lang.Object key)
                                            throws java.lang.Exception

Overwrite this method to load one single row bean

Parameters:

key - The key

Returns:

row bean

Throws:

java.lang.Exception - An error ocurred while loading the row bean

clear

public void clear()

Clears the current keyset

setupKeys

public void setupKeys()
               throws java.lang.Exception

Use this method to set up the keys collection explicit

Throws:

java.lang.Exception - An error ocurred while loading the keyset

getRowBean

private java.lang.Object getRowBean(int index)

Returns the row bean for the given index

Parameters:

index - Element index

Returns:

row bean

getElementAt

public java.lang.Object getElementAt(int index)

Description copied from interface: ListDataModel

Returns the (row) object for the specified index. This can be a display object (view helper) whose properties will be accessed within the columns of a List- or TreeControl

Specified by:

getElementAt in interface ListDataModel

Parameters:

index - A zero based index

Returns:

A row object.

See Also:

ListDataModel.getElementAt(int)

getUniqueKey

public java.lang.String getUniqueKey(int index)

Description copied from interface: ListDataModel

Returns a unique key for the row which is specified by the index. This id will be attached in hyperlinks to identify the row/object. This can be a simple row index or a key which correspond to the primary key from the database.

Specified by:

getUniqueKey in interface ListDataModel

Parameters:

index - A zero based index

Returns:

The unique key

See Also:

ListDataModel.getUniqueKey(int)

size

public int size()

Description copied from interface: ListDataModel

Returns the number of rows within the list.

Specified by:

size in interface ListDataModel

Returns:

Number of rows

See Also:

ListDataModel.size()