primeservlet.java

来自「sourse code of a very good book which is」· Java 代码 · 共 26 行

package coreservlets;  

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

public class PrimeServlet extends HttpServlet {
  public void doGet(HttpServletRequest request,
                    HttpServletResponse response)
      throws ServletException, IOException {
    String length = request.getParameter("primeLength");
    ServletContext context = getServletContext();
    synchronized(this) {
      if ((context.getAttribute("primeBean") == null) ||
          (length != null)) {
        PrimeBean primeBean = new PrimeBean(length);
        context.setAttribute("primeBean", primeBean);
      }
      String address = "/WEB-INF/mvc-sharing/ShowPrime.jsp";
      RequestDispatcher dispatcher =
        request.getRequestDispatcher(address);
      dispatcher.forward(request, response);
    }
  }
}