javax.faces.convert.EnumConverter Maven / Gradle / Ivy
/*
* $Id: EnumConverter.java,v 1.8 2007/01/29 06:59:55 rlubke Exp $
*/
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the License). You may not use this file except in
* compliance with the License.
*
* You can obtain a copy of the License at
* https://javaserverfaces.dev.java.net/CDDL.html or
* legal/CDDLv1.0.txt.
* See the License for the specific language governing
* permission and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at legal/CDDLv1.0.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* your own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* [Name of File] [ver.__] [Date]
*
* Copyright 2005 Sun Microsystems Inc. All Rights Reserved
*/
package javax.faces.convert;
import javax.faces.component.StateHolder;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
/**
* {@link Converter} implementation for java.lang.Enum
* (and enum primitive) values.
*
* @since 1.2
*/
public class EnumConverter implements Converter, StateHolder {
// for StateHolder
public EnumConverter() {
}
public EnumConverter(Class targetClass) {
this.targetClass = (Class extends Enum>) targetClass;
}
// ------------------------------------------------------ Manifest Constants
/**
* The standard converter id for this converter.
*/
public static final String CONVERTER_ID = "javax.faces.Enum";
/**
* The message identifier of the {@link javax.faces.application.FacesMessage} to be created if
* the conversion to Enum
fails. The message format
* string for this message may optionally include the following
* placeholders:
*
* {0}
replaced by the unconverted value.
* {1}
replaced by one of the enum constants or the empty
* string if none can be found.
* {2}
replaced by a String
whose value
* is the label of the input component that produced this message.
*
*/
public static final String ENUM_ID =
"javax.faces.converter.EnumConverter.ENUM";
/**
* The message identifier of the {@link javax.faces.application.FacesMessage} to be created if
* the conversion to Enum
fails and no target class has been
* provided. The message format
* string for this message may optionally include the following
* placeholders:
*
* {0}
replaced by the unconverted value.
* {1}
replaced by a String
whose value
* is the label of the input component that produced this message.
*
*/
public static final String ENUM_NO_CLASS_ID =
"javax.faces.converter.EnumConverter.ENUM_NO_CLASS";
// ----------------------------------------------------- Converter Methods
private Class extends Enum> targetClass;
/**
* Convert the value
argument to one of the enum
* constants of the class provided in our constructor. If no
* target class argument has been provided to the constructor of
* this instance, throw a ConverterException
* containing the {@link #ENUM_NO_CLASS_ID} message with proper
* parameters. If the value
argument is null
* or it has a length of zero, return null
.
* Otherwise, perform the equivalent of Enum.valueOf
using
* target class and value
and return the Object
.
* If the conversion fails, throw a ConverterException
* containing the {@link #ENUM_ID} message with proper parameters.
*
*
* @param context the FacesContext
for this request.
* @param component the UIComponent
to which this value
* will be applied.
* @param value the String value
to be converted to
* Object
.
* @throws ConverterException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public Object getAsObject(FacesContext context, UIComponent component,
String value) {
if (context == null || component == null) {
throw new NullPointerException();
}
if (targetClass == null) {
throw new ConverterException(
MessageFactory.getMessage(context,
ENUM_NO_CLASS_ID,
value,
MessageFactory.getLabel(context,
component)));
}
// If the specified value is null or zero-length, return null
if (value == null) {
return (null);
}
value = value.trim();
if (value.length() < 1) {
return (null);
}
try {
return Enum.valueOf(targetClass, value);
} catch (IllegalArgumentException iae) {
throw new ConverterException(
MessageFactory.getMessage(context,
ENUM_ID,
value,
value,
MessageFactory.getLabel(context,
component)));
}
}
/**
* Convert the enum constant given by the value
* argument into a String. If no target class argument has been
* provided to the constructor of this instance, throw a
* ConverterException
containing the
* {@link #ENUM_NO_CLASS_ID} message with proper parameters. If the
* value,/code> argument is null
, return null
.
* If the value is an instance of the provided target class, return its
* string value (value.toString()
). Otherwise, throw a
* {@link ConverterException} containing the {@link #ENUM_ID} message with
* proper parameters.
*
* @throws ConverterException {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
*/
public String getAsString(FacesContext context, UIComponent component,
Object value) {
if (context == null || component == null) {
throw new NullPointerException();
}
if (targetClass == null) {
throw new ConverterException(
MessageFactory.getMessage(context,
ENUM_NO_CLASS_ID,
value,
MessageFactory.getLabel(context,
component)));
}
// If the specified value is null, return null
if (value == null) {
return (null);
}
if (targetClass.isInstance(value)) {
return value.toString();
}
throw new ConverterException(
MessageFactory.getMessage(context,
ENUM_ID,
value,
value,
MessageFactory.getLabel(context,
component)));
}
// ----------------------------------------------------------- StateHolder
public void restoreState(FacesContext facesContext, Object object) {
this.targetClass = (Class extends Enum>) object;
}
public Object saveState(FacesContext facesContext) {
return this.targetClass;
}
private boolean isTransient = false;
public void setTransient(boolean b) {
isTransient = b;
}
public boolean isTransient() {
return isTransient;
}
}