SpringMVC与前端交互案例教程

package cn.tedu;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

//启动类

@SpringBootApplication

public class RunApp {

     public static void main(String[] args) {

         SpringApplication.run(RunApp. class );

     }

}

package cn.tedu.pojo;

//Model用来封装数据

public class Car {

     private int id;

     private String name;

     private double price;

     //Constructor构造方法，用来方便的new

     public Car(){}

     public Car( int id, String name, double price) {

         this .id = id;

         this .name = name;

         this .price = price;

     }

     public int getId() {

         return id;

     }

     public void setId( int id) {

         this .id = id;

     }

     public String getName() {

         return name;

     }

     public void setName(String name) {

         this .name = name;

     }

     public double getPrice() {

         return price;

     }

     public void setPrice( double price) {

         this .price = price;

     }

}

package cn.tedu.controller;

//MVC里的C层，用来接受请求和做出响应(springmvc)

import cn.tedu.pojo.Car;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

@RestController //接受请求，并把json数据返回

@RequestMapping ( "car" )  //规定了url地址的写法

public class CarController {

     @RequestMapping ( "get" )

     public Car get(){

         Car c = new Car( 10 , "BMW" , 19.9 );

         return c ;

     }

}

package cn.tedu.controller;

//MVC里的C层，用来接受请求和做出响应(springmvc)

import cn.tedu.pojo.Car;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

@RestController //接受请求，并把json数据返回

@RequestMapping ( "car" )  //规定了url地址的写法

public class CarController {

     //SpringMVC框架解析请求中的参数

     //http://localhost:8080/car/get5?id=10&name=BMW&price=9.9

     @RequestMapping ( "get5" )

     public void get5(Car c){ //springmvc框架会把请求的参数，封装给car对象

         System.out.println(c.getId()+c.getName()+c.getPrice());

     }

     //http://localhost:8080/car/get4?id=10&name=BMW

     @RequestMapping ( "get4" )

     public void get4(Integer id,String name){

         //id是用来接受url里id的值，name用来接受url里name的值

         System.out.println(id+name);

     }

     //http://localhost:8080/car/get3?id=10

     @RequestMapping ( "get3" )

//    public void get3(int id){ //参数是基本类型，访问这个方法必须带参数，否则有异常

     public void get3(Integer id){ //参数是引用类型，访问这个方法没带参数就是null

         System.out.println(id);

     }

     //自己解析请求中的参数

     public void get2(){

         String url= "http://localhost:8080/car/get2?id=10&name=BMW&price=9.9" ;

         //先按？切出来，取第二部分，再用&切出来参数名和参数值[id=10,name=BMW,price=9.9]

         String[] s = url.split( "\\?" )[ 1 ].split( "&" );

         for (String ss : s) {

             String key =  ss.split( "=" )[ 0 ];

             String value = ss.split( "=" )[ 1 ] ;

         }

     }

     @RequestMapping ( "get" )

     public Car get(){

         Car c = new Car( 10 , "BMW" , 19.9 );

         return c ;

     }

}

package cn.tedu.controller;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

//对比，请求参数的不同获取方式：get/restful

@RestController

@RequestMapping ( "car2" )

public class CarController2 {

     //1.普通的get方式获取请求参数

     //解析参数：http://localhost:8080/car2/get?id=10&name=BMW&age=10&sex=1

     @RequestMapping ( "get" )

     public String get(Integer id,String name,Integer age,Integer sex){

//        return id+name+age+sex ;//直接把结果展示在浏览器上

         return "{'id':'" +id+ "'}" ; //组织成json串给浏览器展示

     }

     //2.restful方式获取请求参数:通过{}绑定地址中参数的位置 + 通过注解获取{???}的值

     //解析参数：http://localhost:8080/car2/get2/10/BMW/10/1

     @RequestMapping ( "get2/{id}/{name}/{x}/{y}" )

     public void get2( @PathVariable Integer id,

                      @PathVariable String name,

                      @PathVariable    String x,

                      @PathVariable Integer y){

         System.out.println(id);

         System.out.println(name);

         System.out.println(x);

         System.out.println(y);

     }

}

<!DOCTYPE html>

< html >

     < head >

         < meta charset = "utf-8" >

         < title >用get方式提交数据给服务器</ title >

     </ head >

     < body >

         < a href = "http://localhost:8080/user/save?id=857&name=jack&age=666" >点我提交数据get</ a >

         < a href = "http://localhost:8080/user/save2/857/jack/666" >点我提交数据restful</ a >

     </ body >

</ html >

package cn.tedu.controller;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

@RestController

@RequestMapping ( "user" )

public class UserController {

     //1. 解析get的请求参数 http://localhost:8080/user/save?id=857&name=jack&age=666

     @RequestMapping ( "save" )

     public void save(Integer id,String name,Integer age){

         System.out.println(id+name+age);

     }

     //2. 解析restful的请求参数 http://localhost:8080/user/save2/857/jack/666

     //get和restful的区别？

          //get的好处是数据都在地址栏拼接，restful的好处是相对安全

         //restful主要是用来优化、简化get提交数据的写法

     @RequestMapping ( "save2/{x}/{y}/{z}" )

     public void save2( @PathVariable Integer x,

                       @PathVariable String y,

                       @PathVariable Integer z){

         System.out.println(x+y+z);

     }

}

<? xml version = "1.0" encoding = "UTF-8" ?>

< project xmlns = "http://maven.apache.org/POM/4.0.0"

          xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"

          xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" >

     < parent >

         < artifactId >cgb2104boot01</ artifactId >

         < groupId >cn.tedu</ groupId >

         < version >0.0.1-SNAPSHOT</ version >

     </ parent >

     < modelVersion >4.0.0</ modelVersion >

     < artifactId >day13</ artifactId >

     <!--添加jar包的依赖-->

     < dependencies >

         < dependency >

             < groupId >mysql</ groupId >

             < artifactId >mysql-connector-java</ artifactId >

             < version >5.1.48</ version >

         </ dependency >

     </ dependencies >

</ project >

CREATE TABLE ` user ` (

   `id` int (3) default NULL ,

   ` name ` varchar (10) default NULL ,

   `age` int (2) default NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

package cn.tedu.controller;

import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

@RestController

@RequestMapping ( "user" )

public class UserController {

     //1. 解析get的请求参数 http://localhost:8080/user/save?id=857&name=jack&age=666

     @RequestMapping ( "save" )

     public void save(Integer id,String name,Integer age) throws Exception {

//        System.out.println(id+name+age);

         /* 把解析出来的参数，利用jdbc技术入库*/

         //注册驱动

         Class.forName( "com.mysql.jdbc.Driver" );

         //获取连接

         String url = "jdbc:mysql:///cgb2104?characterEncoding=utf8&amp;serverTimezone=Asia/Shanghai" ;

         Connection conn = DriverManager.getConnection(url, "root" , "root" );

         //获取传输器

//        String sql= "insert into user(id,name) values(?,?)";//给指定的字段设置值

         String sql= "insert into user values(?,?,?)" ; //所有字段设置值

         PreparedStatement ps = conn.prepareStatement(sql);

         //给SQL设置参数

         ps.setInt( 1 ,id); //给第一个？设置值

         ps.setString( 2 ,name); //给第二个？设置值

         ps.setInt( 3 ,age); //给第三个？设置值

         //执行SQL

         int rows = ps.executeUpdate();

         //释放资源 -- OOM(OutOfMemory)

         ps.close();

         conn.close();

     }

     //2. 解析restful的请求参数 http://localhost:8080/user/save2/857/jack/666

     //get和restful的区别？

          //get的好处是数据都在地址栏拼接，restful的好处是相对安全

         //restful主要是用来优化、简化get提交数据的写法

     @RequestMapping ( "save2/{x}/{y}/{z}" )

     public void save2( @PathVariable Integer x,

                       @PathVariable String y,

                       @PathVariable Integer z){

         System.out.println(x+y+z);

     }

}