javax.faces.convert.Converter Maven / Gradle / Ivy
Show all versions of jsf-api Show documentation
/*
* $Id: Converter.java,v 1.16 2007/04/27 22:00:07 ofung Exp $
*/
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package javax.faces.convert;
import javax.faces.component.StateHolder;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
/**
* Converter is an interface describing a Java class
* that can perform Object-to-String and String-to-Object conversions
* between model data objects and a String representation of those
* objects that is suitable for rendering.
*
* {@link Converter} implementations must have a zero-arguments public
* constructor. In addition, if the {@link Converter} class wishes to have
* configuration property values saved and restored with the component tree,
* the implementation must also implement {@link StateHolder}.
*
* Starting with version 1.2 of the specification, an exception to the above
* zero-arguments constructor requirement has been introduced. If a converter has
* a single argument constructor that takes a Class instance and
* the Class of the data to be converted is
* known at converter instantiation time, this constructor
* must be used to instantiate the converter instead of the zero-argument
* version. This enables the per-class conversion
* of Java enumerated types.
*
* If any Converter implementation requires a
* java.util.Locale to perform its job, it must obtain that
* Locale from the {@link javax.faces.component.UIViewRoot}
* of the current {@link FacesContext}, unless the
* Converter maintains its own Locale as part
* of its state.
*/
public interface Converter {
/**
* Convert the specified string value, which is associated with
* the specified {@link UIComponent}, into a model data object that
* is appropriate for being stored during the Apply Request
* Values phase of the request processing lifecycle.
*
* @param context {@link FacesContext} for the request being processed
* @param component {@link UIComponent} with which this model object
* value is associated
* @param value String value to be converted (may be null)
* @return null if the value to convert is null,
* otherwise the result of the conversion
* @throws ConverterException if conversion cannot be successfully
* performed
* @throws NullPointerException if context or
* component is null
*/
public Object getAsObject(FacesContext context, UIComponent component,
String value);
/**
* Convert the specified model object value, which is associated with
* the specified {@link UIComponent}, into a String that is suitable
* for being included in the response generated during the
* Render Response phase of the request processing
* lifeycle.
*
* @param context {@link FacesContext} for the request being processed
* @param component {@link UIComponent} with which this model object
* value is associated
* @param value Model object value to be converted
* (may be null)
* @return a zero-length String if value is null,
* otherwise the result of the conversion
* @throws ConverterException if conversion cannot be successfully
* performed
* @throws NullPointerException if context or
* component is null
*/
public String getAsString(FacesContext context, UIComponent component,
Object value);
}