一,创建day13的module
选中project-右键-new-module-选择maven-next-输入module名-finish
二,复习SpringMVC
–1,需求:访问/car/get ,获取汽车数据
–2,创建RunApp类
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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 ); } } |
–3,创建Car类
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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; } } |
–4,创建CarController类
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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 ; } } |
三,SpringMVC解析请求参数
SpringMVC框架,可以自动解析请求中,携带的参数。甚至可以直接封装成Java对象。而不必自己一个个解析参数。
–1,普通的GET提交
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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 ; } } |
–2,RestFul提交
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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); } } |
四,简单的前后端关联
–1,需求
点击页面的a,Get方式提交数据,交给框架解析参数
–2,创建html页面
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<!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 > |
–3,创建UserController类,解析参数
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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); } } |
五,利用JDBC技术,把请求参数入库
–1,添加jdbc的依赖(修改pom.xml)
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<? 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 > |
–2,准备user表
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CREATE TABLE ` user ` ( `id` int (3) default NULL , ` name ` varchar (10) default NULL , `age` int (2) default NULL ) ENGINE=InnoDB DEFAULT CHARSET=utf8; |
–3,修改UserController类的save()
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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&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); } } |
–4,测试
六、总结
本篇文章就到这里了,希望能给你带来帮助,也希望您能够多多关注服务器之家的更多内容!
原文链接:https://blog.csdn.net/u012932876/article/details/117918962