package org.apache.turbine.services.jsp.tags;

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 * reserved.
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 * modification, are permitted provided that the following conditions
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 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
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 *    if and wherever such third-party acknowledgments normally appear.
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 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import java.io.IOException;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagSupport;
import org.apache.turbine.services.jsp.JspService;
import org.apache.turbine.util.DynamicURI;
import org.apache.turbine.util.Log;
import org.apache.turbine.util.RunData;
import org.apache.turbine.util.template.TemplateLink;

/**
  * Supporting class for the TemplateLink tag.
  * Uses the TemplateLink class to construct a URI
  *
  * @author <a href="mailto:ingo@raleigh.ibm.com">Ingo Schuster</a>
  */
public class TemplateLinkTag extends TagSupport
{
     /**
      * template parameter defines the template to set
      * mandatory parameter
      */
     private String template;

     /**
      * The setter for template parameter
      */
     public void setTemplate(String template)
     {
         this.template = template;
     }

     /**
      * action parameter defines the action to set
      * optional parameter
      */
     private String action;

     /**
      * The setter for screen parameter
      */
     public void setAction(String action)
     {
         this.action = action;
     }

     public int doStartTag() throws JspException
     {
         RunData data = 
             (RunData)pageContext.getAttribute(JspService.RUNDATA, 
                                               PageContext.REQUEST_SCOPE);

         TemplateLink link = new TemplateLink( data );
         DynamicURI uri = link.setPage( template );
         if ( action != null ) uri = uri.setAction( action );

         try
         {
             if (uri != null) {
                 pageContext.getOut().print(uri.toString());
             }
         }
         catch (Exception e)
         {
             String message = 
                 "Error processing TemplateLink-tag, parameter: template='"
                 + template + "', action='" +action +"'";
             Log.error(message, e);
             try
             {
                 data.getOut().print( message );
             }
             catch(java.io.IOException ioe) {}
         }

         return EVAL_BODY_INCLUDE;
     }

}