requestfilter.java

来自「JAVA Servlet2.3外文书籍源码」· Java 代码 · 共 39 行

package persistence.requester;

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

public class RequestFilter implements Filter {

  private String attribute = null;
  private FilterConfig filterConfig = null;

  public void destroy() {
    this.attribute = null;
    this.filterConfig = null;
  }
  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    try {
      if (request instanceof HttpServletRequest) {
        System.out.println("Filtering...");
        HttpServletRequest ref = (HttpServletRequest) request;
        HttpSession session = ref.getSession();
        Requester req = (Requester) session.getAttribute(Requester.KEY);
        if (req == null) {
          req = new Requester(ref);
          session.setAttribute(Requester.KEY, req);
        }
        req.addRequest(ref);
      }
    } catch (Throwable t) {
      filterConfig.getServletContext().log("RequestFilter", t);
    }

    chain.doFilter(request, response);
  }

  public void init(FilterConfig filterConfig) throws ServletException {
    this.filterConfig = filterConfig;
  }
}