package com.acme.tag;

import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;

/**
 * A simple Case Tag
 * @author Magnus Rydin
 */

public class CaseTag extends SwitchTag
{

  public CaseTag()
  {
    super();
  }

  public int doStartTag() throws JspTagException
  {
    //The Switch Tag should be our parent Tag
    SwitchTag parent=(SwitchTag)findAncestorWithClass(this,SwitchTag.class);
    //If Switch was not our parent, throw Exception
    if(parent==null)
    {
      throw new JspTagException("Case Tag without Switch Tag");
    }
    try
    {
      //check if values match
      if(parent.getValue().equals(getValue()))
      {
        return EVAL_BODY_INCLUDE;
      }
      else
      {
        return SKIP_BODY;
      }
    }
    catch(NullPointerException e)
    {
      //check if both values are null
      if(parent.getValue()==null && getValue()==null)
      {
        return EVAL_BODY_INCLUDE;
      }
      else
      {
        return SKIP_BODY;
      }
    }
  }
}