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/*
 * 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
 * glassfish/bootstrap/legal/CDDLv1.0.txt or
 * https://glassfish.dev.java.net/public/CDDLv1.0.html.
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * glassfish/bootstrap/legal/CDDLv1.0.txt.  If applicable,
 * add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your
 * own identifying information: Portions Copyright [yyyy]
 * [name of copyright owner]
 *
 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
 *
 * Portions Copyright Apache Software Foundation.
 */ 

package org.apache.taglibs.standard.tag.el.fmt;

import javax.servlet.jsp.JspException;

import org.apache.taglibs.standard.lang.support.ExpressionEvaluatorManager;
import org.apache.taglibs.standard.tag.common.fmt.SetLocaleSupport;

/**
 * A handler for <setLocale> that accepts attributes as Strings
 * and evaluates them as expressions at runtime.
 *
 * @author Jan Luehe
 */

public class SetLocaleTag extends SetLocaleSupport {

    //*********************************************************************
    // 'Private' state (implementation details)

    private String value_;                      // stores EL-based property
    private String variant_;                    // stores EL-based property


    //*********************************************************************
    // Constructor

    /**
     * Constructs a new LocaleTag.  As with TagSupport, subclasses
     * should not provide other constructors and are expected to call
     * the superclass constructor
     */
    public SetLocaleTag() {
        super();
        init();
    }


    //*********************************************************************
    // Tag logic

    // evaluates expression and chains to parent
    public int doStartTag() throws JspException {

        // evaluate any expressions we were passed, once per invocation
        evaluateExpressions();

	// chain to the parent implementation
	return super.doStartTag();
    }

    // Releases any resources we may have (or inherit)
    public void release() {
        super.release();
        init();
    }


    //*********************************************************************
    // Accessor methods

    // for EL-based attribute
    public void setValue(String value_) {
        this.value_ = value_;
    }

    // for EL-based attribute
    public void setVariant(String variant_) {
        this.variant_ = variant_;
    }


    //*********************************************************************
    // Private (utility) methods

    // (re)initializes state (during release() or construction)
    private void init() {
        // null implies "no expression"
	value_ = variant_ = null;
    }

    // Evaluates expressions as necessary
    private void evaluateExpressions() throws JspException {

	// 'value' attribute (mandatory)
	value = ExpressionEvaluatorManager.evaluate(
	    "value", value_, Object.class, this, pageContext);

	// 'variant' attribute (optional)
	if (variant_ != null) {
	    variant = (String) ExpressionEvaluatorManager.evaluate(
	        "variant", variant_, String.class, this, pageContext);
	}
    }
}