org.apache.tapestry.form
Class EnumPropertySelectionModel

java.lang.Object
  org.apache.tapestry.form.EnumPropertySelectionModel

All Implemented Interfaces:

IPropertySelectionModel

public class EnumPropertySelectionModel
extends Object
implements IPropertySelectionModel

Implementation of IPropertySelectionModel that wraps around a set of Enums.

Uses a simple index number as the value (used to represent the option).

The resource bundle from which labels are extracted is usually a resource within the Tapestry application. Since ResourceBundle.getBundle(String, java.util.Locale) uses its caller's class loader, and that classloader will be the Tapestry framework's classloader, the application's resources won't be visible. This requires that the application resolve the resource to a ResourceBundle before creating this model.

Version:

$Id: EnumPropertySelectionModel.java 243791 2004-02-19 17:38:13Z hlship $

Author:

Howard Lewis Ship

Constructor Summary

EnumPropertySelectionModel(org.apache.commons.lang.enum.Enum[] options, ResourceBundle bundle)
Simplified constructor using no prefix.

EnumPropertySelectionModel(org.apache.commons.lang.enum.Enum[] options, ResourceBundle bundle, String resourcePrefix)
Standard constructor.

Method Summary

String	getLabel(int index) Returns the label for an option.
Object	getOption(int index) Returns one possible option.
int	getOptionCount() Returns the number of possible options.
String	getValue(int index) Returns a String used to represent the option in the HTML (as the value of an <option> or <input type=radio>.
Object	translateValue(String value) Returns the option corresponding to a value.

Methods inherited from class java.lang.Object

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

Constructor Detail

EnumPropertySelectionModel

public EnumPropertySelectionModel(org.apache.commons.lang.enum.Enum[] options,
                                  ResourceBundle bundle,
                                  String resourcePrefix)

Standard constructor.

Labels for the options are extracted from a resource bundle. resourceBaseName identifies the bundle. Typically, the bundle will be a .properties file within the classpath. Specify the fully qualified class name equivalent, i.e., for file /com/example/foo/LabelStrings.properties use com.example.foo.LabelStrings as the resource base name.

Normally (when resourcePrefix is null), the keys used to extract labels matches the enumeration id of the option. By convention, the enumeration id matches the name of the static variable.

To avoid naming conflicts when using a single resource bundle for multiple models, use a resource prefix. This is a string which is prepended to the enumeration id (they prefix and enumeration id are seperated with a period).

Parameters:

options - The list of possible values for this model, in the order they should appear. This exact array is retained (not copied).

bundle - The ResourceBundle from which labels may be extracted.

resourcePrefix - An optional prefix used when accessing keys within the bundle. Used to allow a single ResouceBundle to contain labels for multiple Enums.

EnumPropertySelectionModel

public EnumPropertySelectionModel(org.apache.commons.lang.enum.Enum[] options,
                                  ResourceBundle bundle)

Simplified constructor using no prefix.

Method Detail

getOptionCount

public int getOptionCount()

Description copied from interface: IPropertySelectionModel

Returns the number of possible options.

Specified by:

getOptionCount in interface IPropertySelectionModel

getOption

public Object getOption(int index)

Description copied from interface: IPropertySelectionModel

Returns one possible option.

Specified by:

getOption in interface IPropertySelectionModel

getLabel

public String getLabel(int index)

Description copied from interface: IPropertySelectionModel

Returns the label for an option. It is the responsibility of the adaptor to make this value localized.

Specified by:

getLabel in interface IPropertySelectionModel

getValue

public String getValue(int index)

Description copied from interface: IPropertySelectionModel

Returns a String used to represent the option in the HTML (as the value of an <option> or <input type=radio>.

Specified by:

getValue in interface IPropertySelectionModel

translateValue

public Object translateValue(String value)

Description copied from interface: IPropertySelectionModel

Returns the option corresponding to a value. This is used when interpreting submitted form parameters.

Specified by:

translateValue in interface IPropertySelectionModel