requestblocker.java~

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package webtests.filters;

import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;

public class RequestBlocker implements Filter {
  private Properties blockThese = new Properties();
  {
    blockThese.setProperty("company", "FlakyNetworks");
  }
  private ServletContext ctx;
  public void init(javax.servlet.FilterConfig filterConfig) 
         throws ServletException {
    ctx = filterConfig.getServletContext();
    ctx.log("Filter " + filterConfig.getFilterName() + 
                                                " initialized.");
  }
    public void doFilter(javax.servlet.ServletRequest servletRequest,
                       javax.servlet.ServletResponse servletResponse,
                       javax.servlet.FilterChain filterChain)
         throws java.io.IOException, javax.servlet.ServletException {
    HttpServletRequest hsr = (HttpServletRequest)servletRequest;
    final HttpServletResponse resp = (HttpServletResponse)servletResponse;
    boolean block = false;
    String message = null;

    Enumeration paramNames = hsr.getParameterNames();
    while (paramNames.hasMoreElements()) {
      String paramName = (String)paramNames.nextElement();
      System.out.println("paramName=" +paramName);
      String[] paramValues =hsr.getParameterValues(paramName);
      
      for (Enumeration propertyNames = blockThese.propertyNames(); propertyNames.hasMoreElements() ;) {	    
	String propertyName = (String)propertyNames.nextElement();
	System.out.println("propertyName =" + propertyName);
	String propertyValue = (String)blockThese.getProperty(propertyName);
	String paramValue = paramValues[0];
	System.out.println("paramValue =" + paramValue);
	if(paramName.equals(propertyName)&&paramValue.equals(propertyValue))
	  {
	    System.out.println("send to Error Page");
	    block = true;
	    message = new String("Request for "+propertyName+" "+propertyValue+" rejected.");
	    // resp.sendError(resp.SC_SERVICE_UNAVAILABLE, "Request for "+propertyName+" "+propertyValue+" rejected.");
	  }
	else
	  {
	    //filterChain.doFilter(hsr, resp);
	  }
      }
    }

    if (block==true)
      {
	resp.sendError(resp.SC_SERVICE_UNAVAILABLE, message);}
    else
      {
    filterChain.doFilter(hsr, resp);
      }
    }
  public void destroy() {
  }
}