Servlet

• extends HttpServlet
• HttpServletRequest HttpServletResponse
• throws ServletException, IOException
• web.xml中的配置信息
  

ServletContext

• 获取：getServletContext();
• 保存：context.setAttribute("times", times)

ServletConfig-获取servlet的配置信息

• 获取：ServletConfig config = this.getServletConfig()
• 获取参数名所对应的参数值：String param = config.getInitParameter("参数名")
  

response

• 设置编码：

  resp.setContentType("text/html;charset=GB2312");
  resp.setContentType("text/html;charset=utf-8");
  

• 得到输出流对象：

  PrintWriter out = resp.getWriter();
  out.println("XXX");
  

• 禁止浏览器缓存：

  resp.setDateHeader("Expires", 0);
  resp.setHeader("Cache-Control", "no-cache");
  resp.setHeader("Pragma", "no-cache");
  

• 实现重定向：

  response.sendRedirect(request.getContextPath() + "/index.jsp");
  

request

• 实现请求转发（留头不留体）

  request.getRequestDispatcher("/TwoServlet").forward(request, response);
  

• 实现请求包含

  request.getRequestDispatcher("/TwoServlet").include(request, response);
  

• Referer 实现防盗链

  // Referer 说明请求头来源
  request.getHeader("Referer");
  

Cookie

• 获取所有的cookie

  Cookie[] cookies = request.getCookies();
  

• 获取第i个cookie的键和值

  cookies[i].getName();
  cookies[i].getValue();
  

• 创建cookie

  // 创建cookie
  Cookie cookie = new Cookie(键, 值);
  // 设置保存时间
  cookie.setMaxAge(60 * 60);
  // 设置路径：访问chapter05下资源时回送cookie
  cookie.setPath("/chapter05");
  // 发送cookie
  response.addCookie(cookie);
  

Session

• 创建或者获得用户的Session对象

  HttpSession session = req.getSession();
  

• 获取属性对应的值

  session.getAttribute("cart");
  

• 设置session

  session.setAttribute("cart", cart);
  

• 创建cookie存放Session的标识号

  Cookie cookie = new Cookie("JSESSIONID", session.getId());
  cookie.setMaxAge(60 * 30);
  cookie.setPath("/chapter05");
  resp.addCookie(cookie);
  

Filter

• 编写web.xml文件，设置对MyServlet的拦截
  

Listener

• 编写一个MyAttributeListener类，该类实现了ServletContextAttributeListener、HttpSessionAttributeListener和ServletRequestAttributeListener接口，并实现该接口中的所有方法

  public class MyAttributeListener implements ServletContextAttributeListener,
  		HttpSessionAttributeListener, ServletRequestAttributeListener {
  	public void attributeAdded(ServletContextAttributeEvent sae) {
  		String name = sae.getName();
  		System.out.println("ServletContext添加属性：" + name + "="
  				+ sae.getServletContext().getAttribute(name));
  	}
  	public void attributeRemoved(ServletContextAttributeEvent sae) {
  		String name = sae.getName();
  		System.out.println("ServletContext移除属性: " + name);
  	}
  	public void attributeReplaced(ServletContextAttributeEvent sae) {
  		String name = sae.getName();
  		System.out.println("ServletContext替换属性：" + name + "="
  				+ sae.getServletContext().getAttribute(name));
  	}
  	public void attributeAdded(HttpSessionBindingEvent hbe) {
  		String name = hbe.getName();
  		System.out.println("HttpSession添加属性：" + name + "="
  				+ hbe.getSession().getAttribute(name));
  	}
  	public void attributeRemoved(HttpSessionBindingEvent hbe) {
  		String name = hbe.getName();
  		System.out.println("HttpSession移除属性: " + name);
  	}
  	public void attributeReplaced(HttpSessionBindingEvent hbe) {
  		String name = hbe.getName();
  		System.out.println("HttpSession替换属性：" + name + "="
  				+ hbe.getSession().getAttribute(name));
  	}
  	public void attributeAdded(ServletRequestAttributeEvent sra) {
  		String name = sra.getName();
  		System.out.println("ServletRequest添加属性：" + name + "="
  				+ sra.getServletRequest().getAttribute(name));
  	}
  	public void attributeRemoved(ServletRequestAttributeEvent sra) {
  		String name = sra.getName();
  		System.out.println("ServletRequest移除属性: " + name);
  	}
  	public void attributeReplaced(ServletRequestAttributeEvent sra) {
  		String name = sra.getName();
  		System.out.println("ServletRequest替换属性：" + name + "="
  				+ sra.getServletRequest().getAttribute(name));
  	}
  }
  

• 在web.xml文件中，部署MyAttributeListener事件监听器
  

数据库

• 请编写一个用于读取数据库中users表信息的JDBC程序，要求分别获取字段id、name、password和email字段的值