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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.common.fmt;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.tagext.BodyTagSupport;
import javax.servlet.jsp.tagext.Tag;

import org.apache.taglibs.standard.resources.Resources;

/**
 * Support for tag handlers for <param>, the message argument
 * subtag in JSTL 1.0 which supplies an argument for parametric replacement
 * to its parent <message> tag.
 *
 * @see MessageSupport
 * @author Jan Luehe
 */

public abstract class ParamSupport extends BodyTagSupport {

    //*********************************************************************
    // Protected state

    protected Object value;                          // 'value' attribute
    protected boolean valueSpecified;	             // status


    //*********************************************************************
    // Constructor and initialization

    public ParamSupport() {
	super();
	init();
    }

    private void init() {
	value = null;
	valueSpecified = false;
    }


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

    // Supply our value to our parent  tag
    public int doEndTag() throws JspException {
	Tag t = findAncestorWithClass(this, MessageSupport.class);
	if (t == null) {
	    throw new JspTagException(Resources.getMessage(
                            "PARAM_OUTSIDE_MESSAGE"));
	}
	MessageSupport parent = (MessageSupport) t;

	/*
	 * Get argument from 'value' attribute or body, as appropriate, and
	 * add it to enclosing  tag, even if it is null or equal
	 * to "".
	 */
	Object input = null;
        // determine the input by...
	if (valueSpecified) {
	    // ... reading 'value' attribute
	    input = value;
	} else {
	    // ... retrieving and trimming our body (TLV has ensured that it's
	    // non-empty)
	    input = bodyContent.getString().trim();
	}
	parent.addParam(input);

	return EVAL_PAGE;
    }

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