优化Servlet
目的
减少Servlet的数量，现在是一个功能一个Servlet，将其优化为一个模块一个Servlet，
相当于在数据库中一张表对应一个Servlet，在Servlet中提供不同的方法，完成用户的请求。
BaseServlet
public class BaseServlet extends HttpServlet {
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//System.out.println("baseServlet的service方法被执行了...");
//完成方法分发
//获取请求路径
String uri = req.getRequestURI();// /travel/user/add
System.out.println("请求方法"+uri);// /travel/user/add
//获取方法名称
String methodName = uri.substring(uri.lastIndexOf('/') + 1);
System.out.println("方法名称"+methodName);
//获取方法对象Method
//谁调用我我代表谁
System.out.println(this);
try {
//忽略访问权限修饰符，获取方法
Method method = this.getClass().getMethod(methodName, HttpServletRequest.class, HttpServletResponse.class);
//执行方法
//暴力反射
// method.setAccessible(true);true
method.invoke(this,req,resp);
} catch (NoSuchMethodException e) {
throw new RuntimeException(e);
} catch (IllegalAccessException e) {
throw new RuntimeException(e);
} catch (InvocationTargetException e) {
throw new RuntimeException(e);
}
}
}
UserServlet
@WebServlet("/user/*") // /user/add /user/find
public class UserServlet extends BaseServlet {
public void add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("userServlet的add方法...");
}
public void find(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("userServlet的find方法...");
}
}
CategoryServlet
@WebServlet("/category/*")
public class CategoryServlet extends BaseServlet {
public void add(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("CategoryServlet的add方法...");
}
public void find(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("CategoryServlet的find方法...");
}
}
调用其他方法进行优化
UserServlet
@WebServlet("/user/*") // /user/add /user/find
public class UserServlet extends BaseServlet {
//声明UserService业务对象
private UserService service = new UserServiceImpl();
/*
注册功能
*/
public void regist(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//验证校验
String check = request.getParameter("check");
//从sesion中获取验证码
HttpSession session = request.getSession();
String checkcode_server = (String) session.getAttribute("CHECKCODE_SERVER");
session.removeAttribute("CHECKCODE_SERVER");//为了保证验证码只能使用一次
//比较
if(checkcode_server == null || !checkcode_server.equalsIgnoreCase(check)){
//验证码错误
ResultInfo info = new ResultInfo();
//注册失败
info.setFlag(false);
info.setErrorMsg("验证码错误");
//将info对象序列化为json
ObjectMapper mapper = new ObjectMapper();
String json = mapper.writeValueAsString(info);
response.setContentType("application/json;charset=utf-8");
response.getWriter().write(json);
return;
}
//1.获取数据
Map<String, String[]> map = request.getParameterMap();
//2.封装对象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//3.调用service完成注册
//UserService service = new UserServiceImpl();
boolean flag = service.regist(user);
ResultInfo info = new ResultInfo();
//4.响应结果
if(flag){
//注册成功
info.setFlag(true);
}else{
//注册失败
info.setFlag(false);
info.setErrorMsg("注册失败!");
}
//将info对象序列化为json
ObjectMapper mapper = new ObjectMapper();
String json = mapper.writeValueAsString(info);
//将json数据写回客户端
//设置content-type
response.setContentType("application/json;charset=utf-8");
response.getWriter().write(json);
}
/*
登录功能
*/
public void login(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.获取用户名和密码数据
Map<String, String[]> map = req.getParameterMap();
//2.封装User对象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//3.调用Service查询
//UserService service = new UserServiceImpl();
User u = service.login(user);
ResultInfo info = new ResultInfo();
//4.判断用户对象是否为null
if(u == null){
//用户名密码或错误
info.setFlag(false);
info.setErrorMsg("用户名密码或错误");
}
//5.判断用户是否激活
if(u != null && !"Y".equals(u.getStatus())){
//用户尚未激活
info.setFlag(false);
info.setErrorMsg("您尚未激活，请激活");
}
//6.判断登录成功
if(u != null && "Y".equals(u.getStatus())){
req.getSession().setAttribute("user",u);//登录成功标记
//登录成功
info.setFlag(true);
}
//响应数据
ObjectMapper mapper = new ObjectMapper();
resp.setContentType("application/json;charset=utf-8");
mapper.writeValue(resp.getOutputStream(),info);
}
/*
查找单个对象功能
*/
protected void findOne(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//从session中获取登录用户
Object user = req.getSession().getAttribute("user");
//将user写回客户端
ObjectMapper mapper = new ObjectMapper();
resp.setContentType("application/json;charset=utf-8");
mapper.writeValue(resp.getOutputStream(),user);
}
/*
推出功能
*/
protected void exit(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1.销毁session
req.getSession().invalidate();
//2.跳转登录页面
resp.sendRedirect(req.getContextPath() + "/login.html");
}
/*
激活功能
*/
protected void active(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//获取激活码
String code = req.getParameter("code");
if (code != null) {
//调用Service完成激活
//UserServiceImpl service = new UserServiceImpl();
boolean flag = service.active(code);
//判断标记
String msg = null;
if (flag) {
//激活成功
msg = "激活成功，请<a href='login.html'>登录</a>";
} else {
//激活失败
msg = "激活失败，请联系管理";
}
resp.setContentType("text/html;charset=utf-8");
resp.getWriter().write(msg);
}
}
}
标签：info,BaseServlet,Userservlet,resp,req,json,user,933,new From： https://www.cnblogs.com/agzq/p/17167045.html