package at.gv.egovernment.moa.id.util;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

/**
 * @author rschamberger
 *  
 */
/**
 * A Filter class wich uses the InOrderServletRequestWrapper to provide servlets a more precise
 * implementation of the getParameter* family. This implementation cares about the order of the parameters
 * from Query String and HTTP POST Body. Use this as Filter class for Servlets which such needs.
 * 
 * @author Rudolf Schamberger
 * @version $Id$
 */
public class ParameterInOrderFilter implements Filter
{

  /**
   * filterConfig
   */
  private FilterConfig filterConfig;

  /**
   * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
   */
  public final void init(final FilterConfig config)
  {
    this.filterConfig = config;
  }

  /**
   * @see javax.servlet.Filter#destroy()
   */
  public final void destroy()
  {
  };

  /**
   * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse,
   *      javax.servlet.FilterChain)
   */
  public final void doFilter(final ServletRequest request, final ServletResponse response,
    final FilterChain chain) throws IOException, ServletException
  {
    InOrderServletRequestWrapper sRequ = new InOrderServletRequestWrapper((HttpServletRequest) request,
      filterConfig.getServletContext());
    //parse the Query (and Body) parameters
    sRequ.parseParameters((HttpServletRequest) request);
    //process the rest of filter chain
    chain.doFilter(sRequ, response);
  }
}