SpringBooot

目录

一、简介

1、使用原因

2、JavaConfig

（1）Configuration注解

（2）Bean注解

（3）ImportResource注解

（4）PropertyResource注解

（5）案例

3、简介

4、特征

 5、SpringBoot案例

 6、SpringBoot配置文件

二、多环境配置

三、@Value 注解@ConfigurationProperties注解

四、SpringBoot使用jsp

五、SpringBoot使用容器

六、CommandLineRunner接口, ApplicationRunner接口

 七、拦截器

八、servlet

九、过滤器

十、SpringBoot字符集过滤器

1、spingmvc自带的

2、根据属性文件

十一、SpringBoot整合Mybatis

1、 @mapper

2、 @MapperScan

十二、SpringBoot事务

1、Spring框架中的事务

2、Springboot中使用事务,

十三、RESTFUL 架构风格

---

一、简介

1、使用原因

（1、）因为spring,springmvc需要使用的大量的配置文件(xml)

             还需要配置各种对象，把使用的对象放入到spring容器中才能使用对象

             需要了解其它框架配置规则

（2、）springboot,就相当于不需要配置文件 spring+springmvc.常用的框架和第三方都已经配置好了.直接拿来使用就可以

（3、）Springboot开发效率高，使用方便

2、JavaConfig

JavaConfig: 使用java类作为XML配置文件的替代。

                    是配置spring容器的纯JAVA的方式

                   在这个java类这可以创建java对象，把对象放入spring容器中(注入到容器)

（1）Configuration注解

放在一个类的上面,表示这个类是作为配置文件使用的.

（2）Bean注解

声明对象，把对象注入到容器中

（3）ImportResource注解

作用导入其它的xml配置文件

相当于<import resource="文件.xml"/>

（4）PropertyResource注解

作用:读取properties属性配置文件，使用配置文件可以实现外部化配置

在程序代码之外提供数据.

步骤：

<1>resources目录下,创建properties 文件，使用 key =value的格式提供数据

<2>PropertyResource指定 properties文件的位置

<3>使用@Value(value="${key")

（5）案例

package com.iotek.vo;/*** @Author:* @CreateTime: 2023-04-03  16:52*/
public class Car {private String name;private String color;private String brand;public Car() {super();}public Car(String name, String color, String brand) {this.name = name;this.color = color;this.brand = brand;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getColor() {return color;}public void setColor(String color) {this.color = color;}public String getBrand() {return brand;}public void setBrand(String brand) {this.brand = brand;}@Overridepublic String toString() {return "Car{" +"name='" + name + '\'' +", color='" + color + '\'' +", brand='" + brand + '\'' +'}';}
}

package com.iotek.vo;import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;/*** @Author:* @CreateTime: 2023-04-03  17:24*/
@Component("employee")
public class Employee {@Value("${employee.name}")private String name;@Value("${employee.age}")private Integer age;@Overridepublic String toString() {return "Employee{" +"name='" + name + '\'' +", age=" + age +'}';}
}

package com.iotek.vo;/*** @Author:* @CreateTime: 2023-04-03  16:25*/
public class Student {private String name;private Integer age;private String address;public Student() {super();}public Student(String name, Integer age, String address) {this.name = name;this.age = age;this.address = address;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}@Overridepublic String toString() {return "Student{" +"name='" + name + '\'' +", age=" + age +", address='" + address + '\'' +'}';}
}

package com.iotek.config;import com.iotek.vo.Student;
import org.springframework.context.annotation.*;/*** @Author:* @CreateTime: 2023-04-03  16:24*/
//Configuration 表示当前类是作为配置文件使用的，用来配置容器，位置在类上
//PropertySource  加载配置文件
//@ComponentScan  扫描
@Configuration
@ImportResource(value = "classpath:applicationContext.xml")
@PropertySource(value = "classpath:config.properties")
@ComponentScan(basePackages="com.iotek.vo")
public class SpringConfig {/*** 创建方法:方法的返回值是对象,在方法的上面加入@Bean* 方法的返回值对象就注入到容器中** @Bean 把对象注入到Spring容器中  相当于<bean></bean>* @Bean 不指定对象的名称，默认是方法名是ID**/@Beanpublic Student createStudent(){Student student = new Student();student.setName("蓉儿");student.setAge(23);student.setAddress("台湾");return  student;}/*** 指定对象在容器中的名称<bean>的ID属性**/@Bean(name = "s2")public Student createStudent2(){Student student = new Student();student.setName("祖儿");student.setAge(26);student.setAddress("杭州");return  student;}
}

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><bean id="car" class="com.iotek.vo.Car"><property name="name" value="奥迪"/><property name="color" value="黑"/><property name="brand" value="大众"/></bean>
</beans>

beans.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd"><bean id="s1" class="com.iotek.vo.Student"><property name="name" value="小青"/><property name="age" value="22"/><property name="address" value="上海"/></bean>
</beans>

config.properties

employee.name=小花
employee.age=33

package com.iotek;import com.iotek.config.SpringConfig;
import com.iotek.vo.Car;
import com.iotek.vo.Employee;
import com.iotek.vo.Student;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;/*** @Author:* @CreateTime: 2023-04-03  16:30*/
public class SpringTest {@Testpublic void test1(){ApplicationContext applicationContext = new ClassPathXmlApplicationContext("beans.xml");Student student = (Student) applicationContext.getBean("s1");System.out.println("student容器对象----"+student);//student容器对象----Student{name='小青', age=22, address='上海'}}@Testpublic void test2(){ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfig.class);Student student = (Student) applicationContext.getBean("createStudent");System.out.println("JavaConfig容器对象----"+student);//JavaConfig容器对象----Student{name='蓉儿', age=23, address='台湾'}}@Testpublic void test3(){ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfig.class);Student student = (Student) applicationContext.getBean("s2");System.out.println("JavaConfig容器对象----"+student);//JavaConfig容器对象----Student{name='祖儿', age=26, address='杭州'}}@Testpublic void test4(){ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfig.class);Car car = (Car) applicationContext.getBean("car");System.out.println("JavaConfig容器ImportResource注解对象----"+car);//JavaConfig容器ImportResource注解对象----Car{name='奥迪', color='黑', brand='大众'}}@Testpublic void test5(){ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfig.class);Employee employee = (Employee) applicationContext.getBean("employee");System.out.println("JavaConfig容器PropertySource注解对象----"+employee);//JavaConfig容器PropertySource注解对象----Employee{name='小花', age=33}}
}

3、简介

springboot是spring中的一个成员.可简化 spring,springmvc的使用。它的核心还是lOC容器.

4、特征

• 创建独立的 Spring 应用程序

• 直接嵌入Tomcat，Jetty或Undertow（无需部署WAR文件）

• 提供“starter”依赖项以简化构建配置

       比如使用mybatis框架，需要在spring项目中，配置 mybatis的对象sqlsessionFactory, Dao的代理对象，在springboot项目中，在POM.xml里面加入了一个 mybatis spring.boot starter依赖。

• 尽可能自动配置 Spring 和第三方库

• 提供了健康检查，统计，外部化配置.

• 无需生成代码，也无需 XML 配置 

 5、SpringBoot案例

@SpringBootConfiguration注解标注的类，可以作为配置文件使用的，可以使用bean声明对象，并注入容器配置文件
@EnableAutoConfiguration启用自动配置，把Java对象配置好，注入到spring容器中
@ComponentScan扫描器，找到注解，根据注解的功能创建好，给属性赋值等等.默认扫描包:@ComponentScan所在的类所在的包和子包.

package com.iotek.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;/*** @Author:* @CreateTime: 2023-04-03  18:17*/
@Controller
public class HelloSpringboot {@RequestMapping(value = "/hello")@ResponseBody//响应public String helloSpringBoot(){return "欢迎使用SpringBoot框架";}
}

 6、SpringBoot配置文件

配置文件application

扩展名：properties(k=v)  yml

使用application.properties       application.yml

application.properties

#设置端口号
#server.port=8022
#设置访问应用上下文路径 contextpath
#server.servlet.context-path=/myboot

application.yml

server:port: 8044servlet:context-path: /myboot2

二、多环境配置

有开发环境、测试环境，上线环境

每个环境有不同的配置信息，比如:端口，上下文件，数据库 URL，用户名，密码等等

使用多环境配置文件，可以方便的切换不同的配置

使用方式:创建多个配置文件，名称规则application-环境名称.properties(yml)

创建开发环境的配置文件：applicatio-dev.properties(application-dev.yml)

创建测试环境的配置文件：application-test.properties

application.properties

#激活使用哪个配置文件
spring.profiles.active=test

三、@Value 注解@ConfigurationProperties注解

@ConfigurationProperties把配置文件的数据映射为java对象。

属性: prefix配置文件中的某些key的开头的内容.

package com.iotek.vo;import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;/*** @Author:* @CreateTime: 2023-04-03  21:27*/
@Component
@ConfigurationProperties(prefix = "employee")
public class EmployeeInfo {private String name;private Integer age;private String address;public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getAddress() {return address;}public void setAddress(String address) {this.address = address;}@Overridepublic String toString() {return "EmployeeInfo{" +"name='" + name + '\'' +", age=" + age +", address='" + address + '\'' +'}';}
}

package com.iotek.controller;import com.iotek.vo.EmployeeInfo;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;import javax.annotation.Resource;/*** @Author:* @CreateTime: 2023-04-03  21:11*/
@Controller
public class EmployeeController {@Value("${server.port}")private Integer port;@Value("${server.servlet.context-path}")private String contextPath;@Value("${employee.name}")private String name;@Value("${employee.age}")private Integer age;@Value("${employee.address}")private String address;@Resourceprivate EmployeeInfo info;@RequestMapping(value = "/data")@ResponseBodypublic String queryData(){return "name="+name+" age=" + age +" address=" + address+"；访问路径=" + contextPath+" 端口号="+port;}@RequestMapping(value = "/info")@ResponseBodypublic String queryEmployeeInfo(){return info.toString();}
}

application.properties

server.port=8083
server.servlet.context-path=/mydataemployee.name=蓉儿
employee.age=24
employee.address=台湾

四、SpringBoot使用jsp

Springboot不推荐使用jsp，而是使用模板技术代替 jsp

<!-- 编译jsp --><dependency><groupId>org.apache.tomcat.embed</groupId><artifactId>tomcat-embed-jasper</artifactId></dependency><dependency><groupId>javax.servlet</groupId><artifactId>servlet-api</artifactId><version>2.5</version></dependency><dependency><groupId>javax.servlet.jsp</groupId><artifactId>javax.servlet.jsp-api</artifactId><version>2.2.1</version></dependency><dependency><groupId>javax.servlet</groupId><artifactId>jstl</artifactId></dependency><!-- 指定jsp编译后存放的路径 --><resources><resource><!-- jsp原来的路径 --><directory>src/main/webapp</directory><!-- 指定编译后的存放路径 --><targetPath>META-INF/resources</targetPath><!-- 指定处理的目录文件 --><includes><include>**/*.*</include></includes></resource></resources>

server.port=8088
server.servlet.context-path=/myboot#视图解析器
#前缀  后缀
spring.mvc.view.prefix=/
spring.mvc.view.suffix=.jsp

<%--Created by IntelliJ IDEA.User: 杪&秋Date: 2023/4/4Time: 10:39To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head><title>Title</title>
</head>
<body><h1>使用JSP，显示控制器的数据${data}</h1>
</body>
</html>

package com.iotek.controller;import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;import javax.servlet.http.HttpServletRequest;/*** @Author:* @CreateTime: 2023-04-04  10:41*/
@Controller
public class ShowDataController {@RequestMapping(value ="showdata")public String showData(Model model){model.addAttribute("data","小青");return "index";//逻辑视图名}
}

五、SpringBoot使用容器

想在通过代码，从容器获取对象

SpringApplication.run(Application.class args);返回值获取容器.

public interface ConfigurableApplicationContext extends ApplicationContext, Lifecycle, Closeable {

package com.iotek.service;/*** @Author:* @CreateTime: 2023-04-04  11:48*/
public interface UserService {void sayHello(String name);
}

package com.iotek.service.impl;import com.iotek.service.UserService;
import org.springframework.stereotype.Service;/*** @Author:* @CreateTime: 2023-04-04  11:49*/
@Service(value = "userService")
public class UserServiceImpl implements UserService {@Overridepublic void sayHello(String name) {System.out.println("say hello" + name);//say hello小花}
}

package com.iotek;import com.iotek.service.UserService;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;@SpringBootApplication
public class Application {public static void main(String[] args) {//手动获取容器对象ConfigurableApplicationContext context = SpringApplication.run(Application.class, args);UserService userService = (UserService)context.getBean("userService");userService.sayHello("小花");}}

六、CommandLineRunner接口, ApplicationRunner接口

这两个接口都有一个run方法，执行时间在容器对象创建好后，自动执行run()方法

可以完成自定义的在容器对象创建好的一些操作

public interface CommandLineRunner {void run(String... args) throws Exception;
}

public interface ApplicationRunner {void run(ApplicationArguments args) throws Exception;
}

 案例：

package com.iotek.service;public interface UserService {String sayHello(String name);
}

package com.iotek.service.impl;import com.iotek.service.UserService;
import org.springframework.stereotype.Service;/*** @Author:* @CreateTime: 2023-04-04  12:18*/
@Service(value = "userService")
public class UserServiceImpl implements UserService {@Overridepublic String sayHello(String name) {return "say hello---"+name;}
}

package com.iotek;import com.iotek.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;import javax.annotation.Resource;@SpringBootApplication
public class Application implements CommandLineRunner {@Autowiredprivate UserService userService;public static void main(String[] args) {System.out.println("创建容器对象之前准备工作...........");SpringApplication.run(Application.class, args);System.out.println("创建容器对象之后...........");}@Overridepublic void run(String... args) throws Exception {//自定义的操作，读取文件、数据库等等。。。。。。。。。。String message = userService.sayHello("祖儿");System.out.println(message);System.out.println("容器对象创建好，执行的方法............");}
}

 七、拦截器

拦截器是spirngmvc中一种对象，能拦截对controller的请求.

自定义拦截器：

1、创建springmvc框架的handlerlnterceptor接口

//请求方法处理前执行@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {return true;}//请求方法处理后执行@Overridepublic void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {}//处理后执行@Overridepublic void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {HandlerInterceptor.super.afterCompletion(request, response, handler, ex);}

package com.iotek.web;import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;/*** @Author:* @CreateTime: 2023-04-04  14:48*/
public class LoginInterceptor implements HandlerInterceptor {@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {System.out.println("执行拦截器..........preHandle");return true;}
}

package com.iotek.config;import com.iotek.web.LoginInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;/*** @Author:* @CreateTime: 2023-04-04  15:01*/
@Configuration
public class WebMcvConfig implements WebMvcConfigurer {//添加拦截器对象，注入到容器中@Overridepublic void addInterceptors(InterceptorRegistry registry) {//创建拦截器对象HandlerInterceptor interceptor = new LoginInterceptor();//指定拦截的请求URL地址String path[]={"/user/**"};//指定不拦截的地址String excludePath[] = {"/user/login"};registry.addInterceptor(interceptor).addPathPatterns(path).excludePathPatterns(excludePath);}
}

package com.iotek.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;/*** @Author:* @CreateTime: 2023-04-04  15:06*/
@Controller
public class BootController {@RequestMapping(value = "/user/account")@ResponseBodypublic String userAccount(){return "访问user/account地址";}@RequestMapping(value = "/user/login")@ResponseBodypublic String userLogin(){return "访问user/login地址";}
}

八、servlet

package com.iotek.web;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;/*** @Author:* @CreateTime: 2023-04-04  16:06*/
public class MyServlet extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doPost(req,resp);}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {resp.setContentType("text/html;charset=utf-8");PrintWriter out = resp.getWriter();out.println("执行servlet。。。。。。。。。。。。。");out.flush();out.close();}
}

package com.iotek.config;import com.iotek.web.MyServlet;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** @Author:* @CreateTime: 2023-04-04  16:10*/
@Configuration
public class WebApplicationConfig {@Beanpublic ServletRegistrationBean servletRegistrationBean(){/*ServletRegistrationBean bean = new ServletRegistrationBean(new MyServlet(),"/myServlet");*/ServletRegistrationBean bean = new ServletRegistrationBean();bean.setServlet(new MyServlet());bean.addUrlMappings("/login","/test");return bean;}
}

九、过滤器

package com.iotek.web;import javax.servlet.*;
import java.io.IOException;/*** @Author:* @CreateTime: 2023-04-04  16:27*/
public class MyFilter implements Filter {@Overridepublic void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {System.out.println("执行了过滤器");filterChain.doFilter(servletRequest,servletResponse);}
}

package com.iotek.config;import com.iotek.web.MyFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;/*** @Author:* @CreateTime: 2023-04-04  16:28*/
@Configuration
public class WebAppConfig{@Beanpublic FilterRegistrationBean filterRegistrationBean(){FilterRegistrationBean bean = new FilterRegistrationBean();bean.setFilter(new MyFilter());bean.addUrlPatterns("/user/*");return bean;}
}

package com.iotek.controller;import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;/*** @Author:* @CreateTime: 2023-04-04  16:31*/
@Controller
public class FilterController {@RequestMapping(value = "/user/account")@ResponseBodypublic String userAccount(){return "user/account";}@RequestMapping(value = "/query")@ResponseBodypublic String queryAccount(){return "/query";}
}

十、SpringBoot字符集过滤器

1、spingmvc自带的

CharacterEncodingFilter:解决post 请求中文乱码的问题

package com.iotek.web;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;/*** @Author:* @CreateTime: 2023-04-07  11:45*/
public class MyServlet extends HttpServlet {@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {resp.setContentType("text/html");PrintWriter pw = resp.getWriter();pw.println("人生如梦");pw.flush();pw.close();}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doPost(req, resp);}
}

package com.iotek.config;import com.iotek.web.MyServlet;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.filter.CharacterEncodingFilter;import java.nio.charset.CharacterCodingException;/*** @Author:* @CreateTime: 2023-04-11  19:30*/
@Configuration
public class WebConfig {@Beanpublic ServletRegistrationBean servletRegistrationBean(){MyServlet myServlet = new MyServlet();ServletRegistrationBean bean = new ServletRegistrationBean(myServlet,"/myServlet");return bean;}//注册过滤器@Beanpublic FilterRegistrationBean filterRegistrationBean(){FilterRegistrationBean bean = new FilterRegistrationBean();//使用springMVC框架的自带的过滤器CharacterEncodingFilter filter = new CharacterEncodingFilter();filter.setEncoding("utf-8");//指定编码filter.setForceEncoding(true);//指定request，response请求都使用Encoding的值bean.setFilter(filter);bean.addUrlPatterns("/*");return bean;}
}

server.servlet.encoding.enabled=false

2、根据属性文件

package com.iotek.web;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;/*** @Author:* @CreateTime: 2023-04-11  20:25*/
public class MyServlet extends HttpServlet {@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {resp.setContentType("text/html");PrintWriter pw = resp.getWriter();pw.println("人生如梦");pw.flush();pw.close();}@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doPost(req, resp);}
}

package com.iotek.config;import com.iotek.web.MyServlet;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;/*** @Author:* @CreateTime: 2023-04-11  20:26*/
@Configuration
public class WebConfig {@Beanpublic ServletRegistrationBean servletRegistrationBean(){MyServlet myServlet = new MyServlet();ServletRegistrationBean bean = new ServletRegistrationBean(myServlet,"/myServlet");return bean;}
}

server.port=8082
server.servlet.context-path=/myboot#开启默认的过滤器
server.servlet.encoding.enabled=true
server.servlet.encoding.charset=utf-8#强制request、response使用charset
server.servlet.encoding.force=true

十一、SpringBoot整合Mybatis

1、 @mapper

mapper:放在dao,接口上面，每个接口都需要使用这个注解。

package com.iotek.pojo;/*** @Author:* @CreateTime: 2023-04-11  20:51*/
public class User {private Integer id;private String name;private Integer age;private String email;public User() {super();}public User(Integer id, String name, Integer age, String email) {this.id = id;this.name = name;this.age = age;this.email = email;}public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Integer getAge() {return age;}public void setAge(Integer age) {this.age = age;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}@Overridepublic String toString() {return "User{" +"id=" + id +", name='" + name + '\'' +", age=" + age +", email='" + email + '\'' +'}';}
}

package com.iotek.dao;import com.iotek.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;@Mapper//mybatis是dao接口，创建此接口前代理对象
@Repository
public interface UserDao {User selectUserById(@Param("userId") Integer id);
}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.iotek.dao.UserDao"><select id="selectUserById" resultType="com.iotek.pojo.User">select * from user where id=#{userId}</select>
</mapper>

package com.iotek.server;import com.iotek.pojo.User;/*** @Author:* @CreateTime: 2023-04-11  21:00*/
public interface UserServer {User queryUser(Integer id);
}

package com.iotek.server.impl;import com.iotek.dao.UserDao;
import com.iotek.pojo.User;
import com.iotek.server.UserServer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;/*** @Author:* @CreateTime: 2023-04-11  21:01*/
@Service(value = "userServer")
public class UserServerImpl implements UserServer {@Autowiredprivate UserDao userDao;@Overridepublic User queryUser(Integer id) {return userDao.selectUserById(id);}
}

package com.iotek.controller;import com.iotek.pojo.User;
import com.iotek.server.UserServer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;/*** @Author:* @CreateTime: 2023-04-11  21:03*/
@Controller
public class UserController {@Autowiredprivate UserServer userServer;@RequestMapping(value = "/user/query")@ResponseBodypublic String queryUser(Integer id){User user = userServer.queryUser(id);return user.toString();}
}

server.port=8088
server.servlet.context-path=/myboot#连接数据库相关信息
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/mybatis_plus?characterEncoding=utf-8
spring.datasource.username=root
spring.datasource.password=123456

<!-- resources插件 --><resources><resource><directory>src/main/java</directory><includes><include>**/*.xml</include></includes></resource></resources>

2、 @MapperScan

找到dao接口和 mapper文件
basePackages: dao接口所在的包名.

十二、SpringBoot事务

1、Spring框架中的事务

1)管理事务的对象,事务管理器（接口，接口有很多的实现类)

JDBC和 mybatis,访问数据库，使用事务管理器DataSourceTranscationManager

2)声明式事务:在 xml配置文件或者使用注解说明事务控制的内容.

控制事务，隔离级别，传播行为，超时时间

3)事务处理方式

<1>Spring框架中的@Transactional

<2>Aspectl框架可以在XML 配置文件中，声明事务控制的内容

2、Springboot中使用事务,

（1、）在业务方法的上面加@Transactional ,加入注解后，方法有事务功能了

（2、）明确在主启动类上面加入@EnableTransationManager

<resources><resource><directory>src/main/resources</directory><includes><include>**/*.*</include></includes></resource></resources>

server.port=8088
server.servlet.context-path=/mybootspring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/mybatis_plus?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true
spring.datasource.username=root
spring.datasource.password=123456mybatis.mapper-locations=classpath:mapper/*.xml
mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

package com.iotek.service.impl;import com.iotek.dao.UserDao;
import com.iotek.pojo.User;
import com.iotek.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;/*** @Author:* @CreateTime: 2023-04-12  10:52*/
@Service
public class UserServiceImpl implements UserService {@Autowiredprivate UserDao userDao;@Transactional//事务表示方法有事务支持，默认使用库的隔离级别REQUIREO 传播行为超时时间 -1  抛出运行时异常，事务回退@Overridepublic int insertUser(User user) {System.out.println("添加用户");int row = userDao.insertUser(user);System.out.println("影响了"+row);int rs = 100 / 0;return row;}
}

package com.iotek.controller;import com.iotek.pojo.User;
import com.iotek.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;/*** @Author:* @CreateTime: 2023-04-12  10:56*/
@Controller
public class UserController {@Autowiredprivate UserService userService;@RequestMapping("addUser")@ResponseBodypublic String UserService(String name,Integer age,String email){User user = new User();user.setName(name);user.setAge(age);user.setEmail(email);int row = userService.insertUser(user);return "添加用户"+row;}
}

package com.iotek;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.transaction.annotation.EnableTransactionManagement;@SpringBootApplication
@EnableTransactionManagement
@MapperScan(basePackages = {"com.iotek.dao"})
public class Application {public static void main(String[] args) {SpringApplication.run(Application.class, args);}}

十三、RESTFUL 架构风格

Rest(Representational state transfer)表现层状态转移Rest是一种接口的架构风格和设计理念，不

是标准.优点:更简洁，更有层次

表现层就是视图层,显示资源的，通过视图页面，jsp等等为示操作资源的结果.状态:资源变化.

转移:资源可以变化的，资源能创建，查询资源，修改资源，删除资源

在url中，使用名词表示资源，以及访问资源的信息，在URL中，使用/分隔对资源的信息

比如:http://localhost:8088/myboot/user/1001

在使用http中的动作请求方式;表示对资源的操作 CRUD

GET查询资源  /post创建资源   /put更新资源  /DELETE删除资源

Rest :使用URL表示资源，使用HITP动作操作资源

注解:
@PathVariable从URL中获取资源

@GetMapping:支持get 请求-->@RequestMapping(method=RequestMethod.Get)

@PostMapping:支持post请求-->@RequestMapping(method=RequestMethod.Post)

@PutMapping:支持put请求-->@RequestMapping(method=RequestMethod.PUT)

@DeleteMapping:支持delete请求--> @RequestMapping(method=RequestMethod.Delete)

@RestController复合注解(@controller 和@ResponseBody)

在 springmvc中有一个过滤器 HiddenHttpMethodFilter

作用把请求post请求转换成put,delete

Springboot application.properties开启使用HiddenHttpMethodFilter过滤器

package com.iotek.controller;import org.springframework.web.bind.annotation.*;/*** @Author:* @CreateTime: 2023-04-12  20:59*/
@RestController
public class MyRestController {/*** @description: @PathVariablec从URL中获取资源* value路径变量名* userId   定义路径变量名* http://localhost:8080/user/1001**/@GetMapping("/user/{userId}")public String queryUser(@PathVariable(value = "userId") Integer uid){return "查询用户"+uid;//查询用户1001}@PostMapping("/user/{name}/{age}")public String insertUser(@PathVariable(value = "name") String uname,@PathVariable(value = "age") Integer uage){return "创建资源---"+"uname=="+uname+"uage=="+uage;}@PutMapping("/put/{id}/{name}")public String modifyUser(@PathVariable(value = "id") String uid,@PathVariable(value = "name") String uname){return "更新资源---"+"uid=="+uid+"uname=="+uname;}@DeleteMapping("/delete/{id}")public String deleteUser(@PathVariable(value = "id") Integer uid){return "删除资源---"+"uid=="+uid;}
}

<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>Title</title>
</head>
<body>
<form action="user/aaaa/12345" method="post"><input type="submit" value="添加用户">
</form>
<form action="put/999/aaa" method="post"><input type="hidden" name="_method" value="put"><input type="submit" value="修改用户">
</form>
<form action="delete/999" method="post"><input type="hidden" name="_method" value="delete"><input type="submit" value="删除用户">
</form>
</body>
</html>

#启用支持put、delete
spring.mvc.hiddenmethod.filter.enabled=true