文章目录

SpringBoot

SpringBoot

1 SpringBoot简介

Spring为应对互联网应用的要求(高可靠，高并发，负载均衡)，推出了SpringBoot和微服务框架SpringCloud

虽然SpringBoot为微服务而生，但多用于单体应用，SpringCloud完全建立在SpringBoot之上
SpringBoot是基于Spring的框架，目的是快速搭建Spring环境
SpringBoot让我们的框架更加便捷化，自动化，简单化
Spring，SpringMVC，MyBatis都可以集成到SpringBoot中
SpringBoot是主要基于注解和编程式配置的实现，在SpringBoot中推荐使用properties或yml文件作为他的配置文件
SpringBoot的开发理念是习惯优于配置，SpringBoot默认不支持JSP,推荐使用HTML或模板引擎技术
SpringBoot中内置Web服务器，不需要搭建外部Web服务器，在SpringBoot开发中更加推荐搭建jar项目而非war项目
SpringBoot推出Starter组件(启动器,每个Starter即为一个应用,它将相关配置、开发包都集成在Starter中)，开发人员在应用中只要引入相关的Starter即可完成配置，从而让开发人员从复杂而繁琐的配置中解脱出来，实现项目的快速搭建

2 SpringBoot的使用

2.1 新建一个基于Maven的项目

2.2 在pom中引入SpringBoot相关配方

引入springBoot父项目

springboot对spring相关版本进行规定,也对spring基础配置进行了约定

   <!--引入springBoot父项目
       springboot对spring相关版本进行规定
	   也对spring基础配置进行了约定
     -->
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.9</version>
    </parent>

添加spring-boot-starter-web依赖

引入后springboot支持web开发

里面包含了 Tomcat web服务器和Spring Boot本身等依赖

   <!--引入spring-boot-starter-web依赖 --> 
   <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

2.3 编写SpringBoot的核心配置类(启动类)

spring启动类，核心配置类，必须在项目的根包下，Springboot组件扫描器会自动扫描当前类所在的包及其子包中的类

@SpringBootApplication:SpringBoot启动类注解，加入该注解后，运行该类的main函数，Spring项目启动

该注解包含三个注解

@EnableAutoConfiguration:启用Spring Boot的自动配置机制
@ComponentScan:启用@Component扫描应用程序所在的软件包
@SpringBootConfiguration:配置类注解相当于spring的 @Configuration 注解

/**
 * spring启动类，核心配置类，必须在项目的根包下，Springboot组件扫描器会自动扫描当前类所在的包及其子包中的类
 * @SpringBootApplication:SpringBoot启动类注解，加入该注解后，运行该类的main函数，Spring项目启动
 */
@SpringBootApplication
public class Application {
    
    
    public static void main(String[] args) {
    
    
        //启动springboot环境
        SpringApplication.run(Application.class,args);
    }
}

2.4 检测是否成功

E:\JDK\bin\java.exe ...
  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v2.7.9)

2023-02-25 14:49:46.465  INFO 2360 --- [           main] com.jiazhong.Application                 : Starting Application using Java 18.0.2.1 on 活着笑 with PID 2360 (D:\Java源码\Classjiazhong\springboot\target\classes started by 活着笑 in D:\Java源码\Classjiazhong\springboot)
2023-02-25 14:49:46.466  INFO 2360 --- [           main] com.jiazhong.Application                 : No active profile set, falling back to 1 default profile: "default"
2023-02-25 14:49:47.640  INFO 2360 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)
2023-02-25 14:49:47.648  INFO 2360 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2023-02-25 14:49:47.648  INFO 2360 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.71]
2023-02-25 14:49:47.906  INFO 2360 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2023-02-25 14:49:47.907  INFO 2360 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1292 ms
2023-02-25 14:49:48.210  INFO 2360 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2023-02-25 14:49:48.218  INFO 2360 --- [           main] com.jiazhong.Application                 : Started Application in 2.246 seconds (JVM running for 4.091)

2.5 添加控制器类检测是否配置成功

@RestController
@RequestMapping("/demo01")
public class DemoControl {
    
    

    @RequestMapping("/demo01")
    public String Demo01(){
    
    
        return "ok";
    }
}

浏览器输入:http://localhost:8080/demo01/demo01测试

2.6 yml和properties配置文件添加SpringBoot项目配置

application.yml

# 服务端配置
server:
  port: 80 # 设置服务器端口号
  servlet:
    context-path: /springboot-project # 设置项目上下文路径(访问根路径)
# 配置日志
logging:
  level:
    root: info
    web:  trace

或application.properties

# 设置服务器端口号
server.port=80
# 设置项目上下文路径(访问根路径)
server.servlet.context-path=/springboot-project
#配置日志
logging.level.root=info
logging.level.web=trace

2.7 编写静态网页

静态网页添加位置，在resources文件夹下新建一个static文件夹，项目中的静态内容都添加到该文件夹下

3 SpringBoot综合应用小Demo

3.1 搭建相关环境

配置SpringBoot环境

引入SpringBoot父项目

Springboot对spring相关版本进行规定,也对spring基础配置进行了约定

 <!--引入springBoot父项目
  父项目对spring相关版本进行规定
  也对spring基础配置进行了约定
  -->
 <parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <version>2.7.9</version>
 </parent>

引入相关依赖

添加spring-boot-starter-web依赖

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

添加热部署

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-devtools</artifactId>
    <optional>true</optional>
</dependency>

核心配置类

@SpringBootApplication
public class Application {
        
        
    public static void main(String[] args) {
        
        
        SpringApplication.run(Application.class, args);
    }
}

整合mybatis

引入mybatis-spring-boot-starter依赖

<dependency>
	<groupId>org.mybatis.spring.boot</groupId>
	<artifactId>mybatis-spring-boot-starter</artifactId>
	<version>2.1.3</version>
</dependency>

引入mysql依赖

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.28</version>
</dependency>

引入durid

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid-spring-boot-starter</artifactId>
    <version>1.2.15</version>
</dependency>

引入其他依赖

fastjson

<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>2.0.7</version>
</dependency>

pagehelper

<dependency>
  <groupId>com.github.pagehelper</groupId>
  <artifactId>pagehelper-spring-boot-starter</artifactId>
  <version>1.4.6</version>
</dependency>

lombok

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
</dependency>

配置application.yml

#服务器配置
server:
  port: 80

# 配置日志
logging:
  level:
    root: info #设置根级别为info级
    com.jiazhong.mapper:  trace  #设置mapper包级别为trance(跟踪级别)
    web: trace    #设置web包级别为trance(跟踪级别)
    
#配置数据库
spring:
  #数据源配置
  datasource:
    #连接属性配置
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf8&useSSL=false
    username: root
    password: root
    #连接池配置
    druid:
      max-active: 100
      min-idle: 10
      initial-size: 10
      max-wait: 1000

mybatis:
  mapper-locations: /mapper/**

3.2 model层

@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")将Java对象转化为JSON数据指定的日期格式

@Data
@AllArgsConstructor
@NoArgsConstructor
public class User implements Serializable {
    
    

    private Integer userId;
    private String username;
    private Integer sex;
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")//将Java对象转化为JSON数据指定的日期格式
    private Date date;
    private Integer age;
    private String address;
}

3.3 controller层

@RequiredArgsConstructor: lombok提供用于为final属性赋值的构造器

@RestController
@RequestMapping("/user")
public class UserController {
    
    
    @Resource
    private UserService userService;
    @RequestMapping("/selectUser")
    public List<User> selectUser(){
    
    
        return userService.selectUser();
    }
    @RequestMapping("/selectUserByUserId")
    public User selectUserByUserId(Integer userId) {
    
    
        return userService.selectUserByUserId(userId);
    }
    @RequestMapping("/addUser")
    public void addUser(@RequestBody User user) {
    
    
        userService.addUser(user);
    }
    @RequestMapping("/deleteUserById")
    public void deleteUserById(Integer... userIds) {
    
    
        userService.deleteUserById(userIds);
    }
    @RequestMapping("/updateUserById")
    public void updateUserById(@RequestBody User user) {
    
    
        userService.updateUserById(user);
    }
}

3.4 service层

UserService接口

public interface UserService {
    
    
    List<User> selectUser();
    User selectUserByUserId(Integer userId);
    void addUser(User user);
    void deleteUserById( Integer... userIds);
    void updateUserById(User user);
}

UserServiceImpl

@Service
public class UserServiceImpl implements UserService {
    
    
    @Resource
    private UserMapper userMapper;
    @Override
    public List<User> selectUser() {
    
    
        return userMapper.selectUser();
    }
    @Override
    public User selectUserByUserId(Integer userId) {
    
    
        return userMapper.selectUserByUserId(userId);
    }
    @Override
    public void addUser(User user) {
    
    
         userMapper.addUser(user);
    }
    @Override
    public void deleteUserById(Integer... userIds) {
    
    
        userMapper.deleteUserById(userIds);
    }
    @Override
    public void updateUserById(User user) {
    
    
         userMapper.updateUserById(user);
    }
}

3.5 mapper层

UserMapper接口

@Repository
public interface UserMapper {
    
    
    //查询所有用户
    @Select("select * from user")
    public List<User> selectUser();

    //根据id查询单个用户
    @Select("select * from user where userId=#{userId}")
    public User selectUserByUserId(Integer userId);

    //添加用户
    @Insert("insert into user values(default,#{username},#{sex},#{date},#{age},#{address})")
    public void addUser(User user);

    //根据id删除用户
    void deleteUserById(@Param("userIds") Integer... userIds);

    //根据id修改用户
    @Update("update user set username=#{username},sex=#{sex},date=#{date},age=#{age},address=#{address} where userId=#{userId}")
    void updateUserById(User user);
}

resources/mapper/UserMapper.xml

<?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.jiazhong.mapper.UserMapper">

    <delete id="deleteUserById">
        <if test="userIds.length!=0">
            delete from user
            <where>
                userId in
                <foreach collection="userIds" open="(" close=")" separator="," item="userId">
                    #{userId}
                </foreach>
            </where>
        </if>
    </delete>
</mapper>

SpringBoot相关配置

添加SpringBoot开发调试工具插件,该工具可以实现项目的热部署

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

设置里设置编译器

在这里插入图片描述

进行启动配置
在这里插入图片描述

学习来自于西安加中实训

Java小记-SpringBoot(超级无敌认真好用，万字收藏篇!!!!)