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/*
 * Copyright (c) 1997, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package jakarta.faces.convert;

import jakarta.faces.component.UIComponent;
import jakarta.faces.context.FacesContext;

/**
 * 
 * {@link Converter} implementation for java.lang.Character (and char primitive) values.
 * 
 */

public class CharacterConverter implements Converter {

    // ------------------------------------------------------ Manifest Constants

    /**
     * 
     * The standard converter id for this converter.
     * 
     */
    public static final String CONVERTER_ID = "jakarta.faces.Character";

    /**
     * 
     * The message identifier of the {@link jakarta.faces.application.FacesMessage} to be created if the conversion to
     * Character fails. 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 CHARACTER_ID = "jakarta.faces.converter.CharacterConverter.CHARACTER";

    /**
     * 
     * The message identifier of the {@link jakarta.faces.application.FacesMessage} to be created if the conversion of the
     * Character value to String fails. The message format string for this message may optionally
     * include the following placeholders:
     * 

     * {0} relaced 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 STRING_ID = "jakarta.faces.converter.STRING";

    // ------------------------------------------------------- Converter Methods

    /**
     * @throws ConverterException {@inheritDoc}
     * @throws NullPointerException {@inheritDoc}
     */
    @Override
    public Object getAsObject(FacesContext context, UIComponent component, String value) {

        if (context == null || component == null) {
            throw new NullPointerException();
        }

        // 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 value.charAt(0);
        } catch (Exception e) {
            throw new ConverterException(MessageFactory.getMessage(context, CHARACTER_ID, value, MessageFactory.getLabel(context, component)), e);
        }
    }

    /**
     * @throws ConverterException {@inheritDoc}
     * @throws NullPointerException {@inheritDoc}
     */
    @Override
    public String getAsString(FacesContext context, UIComponent component, Object value) {

        if (context == null || component == null) {
            throw new NullPointerException();
        }

        // If the specified value is null, return a zero-length String
        if (value == null) {
            return "";
        }

        try {
            return value.toString();
        } catch (Exception e) {
            throw new ConverterException(e);
        }

    }
}