pageInfo = employeeService.selectCondByPage(pageNum, 5, pid);
model.addAttribute("pageInfo", pageInfo);
if (StringUtils.isBlank(pid.toString())){
model.addAttribute("pid","000");
}
model.addAttribute("pid",pid);
return "/employee";
}
```
### jsp
```jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
Title
当前${pageInfo.pageNum }页
总共${pageInfo.pages }页
总共${pageInfo.total }条记录
```
## 当需要接收集合类型时
```java
@Data
@AllArgsConstructor
@NoArgsConstructor
@ToString
public class Department {
private List employees;
}
```
```java
@Controller
public class DepartmentController {
@GetMapping("/toDepAdd")
public String toDepAdd(){
return "/department_add";
}
@PostMapping("/depAdd")
public String toDepAdd(@ModelAttribute Department department){
for (Employee employee : department.getEmployees()) {
System.out.println(employee);
}
return "/department_add";
}
}
```
```jsp
```
## 自定义类型转换器
### utils
```java
@Component
public class DateConverter implements Converter {
@Override
public Date convert(String s) {
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy:MM:dd");
Date date = null;
try {
date = dateFormat.parse(s);
} catch (ParseException e) {
e.printStackTrace();
}
return date;
}
}
```
### springmvc.xml
```xml-dtd
```
### jsp
```jsp
```
### web
```java
@Controller
public class CheckHouseRecordController {
@Resource
private CheckHouseRecordService service;
@GetMapping("/toCheckHouseRecordAdd")
public String toCheckHouseRecordAdd() {
return "/date_add";
}
@PostMapping("/checkHouseRecordAdd")
public String checkHouseRecordAdd(@ModelAttribute CheckHouseRecord record) {
System.out.println(record);
Integer add = service.add(record);
if (add <= 0) {
System.out.println("添加失败！");
}
return "/date_add";
}
}
```
## 异步请求,响应
> @ResponseBody 写在方法上，返回值可以为void
> @RequestBody 写在参数列表上，可以post提交的表单数据，自动封装成pojo实体对象
### pom.xml
```xml
com.fasterxml.jackson.core
jackson-databind
2.11.4
com.fasterxml.jackson.core
jackson-core
2.11.4
com.fasterxml.jackson.core
jackson-annotations
2.11.4
```
### service
```java
@GetMapping(value = "/toSelectOneEmp")
public String toSelectOneEmp(){
return "/select_emp";
}
@PostMapping(value = "/selectOneEmp")
@ResponseBody
public Employee selectOneEmp(@RequestBody Employee employee){
System.out.println(employee);
Integer employeeEid = employee.getEid();
Employee emp = employeeService.selectOneEmp(employeeEid);
return emp;
}
```
### pojo
```java
@Data
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class Employee {
private Integer eid;
private String ename;
private String sex;
private Integer pid;
private String salary;
private String dizhi;
private String job;
private String file;
}
```
### jsp
```javascript
Title
员工编号:
```
## 多条件异步查询
### pojo
```java
public class Employee {
private Integer eid;
private String ename;
private String sex;
private Integer pid;
private Double salary;
private String dizhi;
private String job;
private String file;
}
public class ResultInfo {
private String msg;
private List resultObj;
}
```
### mapper
```java
List selectCondEmpXml(Employee employee);
```
### service
```java
ResultInfo selectCondEmp(Employee employee);
@Override
public ResultInfo selectCondEmp(Employee employee) {
List employees = employeeMapper.selectCondEmpXml(employee);
System.out.println("service"+employees);
ResultInfo resultInfo = new ResultInfo<>();
resultInfo.setResultObj(employees);
if (employees.size() >= 0) {
resultInfo.setMsg("查询成功！");
} else {
resultInfo.setMsg("查询失败！");
}
return resultInfo;
}
```
### controller
```java
@PostMapping(value = "/selectCondEmp")
@ResponseBody
public ResultInfo selectCondEmp(@RequestBody Employee employee) {
System.out.println("进入controller");
System.out.println("controller"+employee);
ResultInfo info = employeeService.selectCondEmp(employee);
return info;
}
```
### jsp
```jsp
Title
```
## 访问静态资源
### springmvc.xml
```xml-dtd
```
## 文件上传
### pom.xml
```xml
commons-fileupload
commons-fileupload
1.3.1
commons-io
commons-io
2.3
```
### springmvc.xml
```xml-dtd
```
### controller
```java
@PostMapping(value = "/empAdd")
public String empAdd(Model model,
HttpServletRequest request,
@ModelAttribute(value = "employee") Employee employee,
@RequestParam MultipartFile upload
) throws IOException {
//服务器保存文件的真实路径
String path = request.getSession().getServletContext().getRealPath("/uploads/");
//判断该文件夹是否存在，如果不存在则创建
File file = new File(path);
if (!file.exists()) {
file.mkdirs();
}
//获取上传文件的原始名称
String filename = upload.getOriginalFilename();
//改造文件名，防止重名发生
String uuid = UUID.randomUUID().toString().replace("-", "");
//执行上传
filename = uuid + filename;
System.out.println("文件名称"+filename);
upload.transferTo(new File(path, filename));
employee.setFile(filename);
Integer empAdd = employeeService.empAdd(employee);
if (empAdd <= 0) {
System.out.println("添加失败！");
}
return "redirect:/queryAllEmp";
}
```
### 上传jsp
```jsp
```
### 显示jsp
```jsp
 |
```
## 拦截器
https://cloud.tencent.com/developer/article/1562376#:~:text=%E6%8B%A6%E6%88%AA%E5%99%A8%20%28interceptor%29%E6%98%AFspringmvc%E4%B8%AD%E7%9A%84%E4%B8%80%E4%B8%AA%20%E7%BB%84%E4%BB%B6%20%EF%BC%8C%E6%98%AF%E8%BF%90%E8%A1%8C%E5%9C%A8%20DispatcherServlet%20%E4%B9%8B%E5%90%8E%EF%BC%8C%E8%BF%90%E8%A1%8C%E5%9C%A8,Controller%20%E4%B9%8B%E5%89%8D%E7%9A%84%20%E6%8B%A6%E6%88%AA%E5%99%A8%E5%8F%AF%E4%BB%A5%E5%86%B3%E5%AE%9A%E5%AF%B9%E6%9F%90%E4%BA%9B%E7%AC%A6%E5%90%88%E6%9D%A1%E4%BB%B6%E7%9A%84%E8%BF%9B%E8%A1%8C%20%E6%8B%A6%E6%88%AA%20%E6%88%96%E8%80%85%20%E6%94%BE%E8%A1%8C%20%EF%BC%8C%E6%89%80%E4%BB%A5%EF%BC%8C%E9%80%9A%E5%B8%B8%E7%94%A8%E4%BA%8E%E5%AF%B9%E4%B8%80%E4%BA%9B%E5%85%B7%E6%9C%89%E7%9B%B8%E5%90%8C%E8%BF%90%E8%A1%8C%E6%9D%A1%E4%BB%B6%E7%9A%84%E5%8A%9F%E8%83%BD%E8%BF%9B%E8%A1%8C%E7%BA%A6%E6%9D%9F
```java
public class EmployeeInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("handler执行之前");
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("handler执行之后，view返回之前");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("view执行之后");
}
}
```
### 登录验证
#### springmvc
```xml-dtd
```
#### interceptor
```java
public class EmployeeInterceptor implements HandlerInterceptor {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
System.out.println("handler执行之前");
String uri = request.getRequestURI();
if (uri.contains("login")) {
return true;
}
if (request.getSession().getAttribute("login") == null) {
response.sendRedirect("/login.jsp");
}
return false;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
System.out.println("handler执行之后，view返回之前");
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
System.out.println("view执行之后");
}
}
```
#### mapper
```java
Employee login(String username);
```
```xml-dtd
```
#### service
```java
Boolean login(String username);
@Override
public Boolean login(String username) {
Employee employee = employeeMapper.login(username);
if (employee == null) {
return false;
}
return true;
}
```
#### web
```java
@PostMapping(value = "/emp_login")
public String login(HttpServletRequest request,
@RequestParam(value = "username") String username,
@RequestParam(value = "password") String password) {
System.out.println(username);
System.out.println(password);
if (employeeService.login(username) && "12345".equals(password)) {
request.getSession().setAttribute("login","2000");
return "/index";
}
return "/login";
}
```
#### jsp
```jsp
```
### 多个拦截器的执行顺序
## 防止多表单提交
### js
```jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
Form表单
```
### session
```jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
form表单
```
### 生成token字符串
```java
package com.zr.utils;
import java.util.Random;
public class TokenProccessor {
/*
*单例模式
*/
private TokenProccessor(){}
private static final TokenProccessor instance = new TokenProccessor();
/**
* 返回类的对象
* @return
*/
public static TokenProccessor getInstance(){
return instance;
}
/**
* 生成Token
*/
public String makeToken(){
String token = (System.currentTimeMillis() + new Random().nextInt(999999999)) + "";
return token;
}
}
```
### 进入页面之前，生成token，传给前端
```java
package com.zr.web;
import com.zr.utils.TokenProccessor
;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import java.io.IOException;
@WebServlet(name = "DoFormSession",urlPatterns = "/DoFormSession")
public class DoFormSession extends HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
String token = TokenProccessor.getInstance().makeToken();//创建令牌
System.out.println("在FormServlet中生成的token："+token);
request.getSession().setAttribute("token", token); //在服务器使用session保存token(令牌)
response.sendRedirect("/add_session.jsp");//跳转到form.jsp页面
}
}
```
### 提交时，验证token隐藏域
```java
package com.zr.web;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebServlet(name = "DoFormToken",urlPatterns = "/DoFormToken")
public class DoFormToken extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
boolean b = isRepeatSubmit(request);//判断用户是否是重复提交
if(b==true){
System.out.println("请不要重复提交!!!");
return;
}
request.getSession().removeAttribute("token");//移除session中的token
System.out.println("处理用户提交请求：添加完毕......");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
/**
* 判断客户端提交上来的令牌和服务器端生成的令牌是否一致
* true：重复提交
* false：没有重复提交
*/
private boolean isRepeatSubmit(HttpServletRequest request) {
String client_token = request.getParameter("token");
//如果用户提交的表单数据中没有token，则是重复提交
if(client_token==null){
return true;
}
//取出存储在Session中的token
String server_token = (String) request.getSession().getAttribute("token");
//如果当前用户的Session中不存在Token，则是重复提交
if(server_token==null){
return true;
}
//存储在Session中的Token)与表单提交的Token不同，则是重复提交
if(!client_token.equals(server_token)){
return true;
}
return false;
}
}
```