目录

一、Hello Spring boot

1.1pom包

1.2启动类

1.3Controller层

二、连接数据库（方法一）

2.1pom包

2.2配置类

2.3配置文件

3.3Controller层

三、连接数据库（方法二，相对简洁）

3.1配置类

        3.2配置文件

四、连接数据库（方法三）

 4.1JdbcProperties

4.2JdbcConfig

五、配置多个yml文件

5.1yml文件

 5.2Controller层：

六、用lombok插件获取get，set和toString方法

6.1安装插件

6.2导入pom坐标

6.3实体类

七、设置拦截器

八、查询操作

8.1配置文件

8.2pojo

8.3Mapper

8.4Service 

8.5Controller

8.6启动类

九、单元测试

一、Hello Spring boot

1.1pom包

  
        1.8
    
    
        spring-boot-starter-parent
        org.springframework.boot
        2.1.5.RELEASE
    
    
    
        org.springframework.boot
        spring-boot-starter-web
    
    

1.2启动类

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

1.3Controller层

@RestController
public class HelloController {
    @GetMapping("hello")
    public String hello(){
        return "hello spring boot";
    }
}

二、连接数据库（方法一）

2.1pom包

在一的pom包中增添如下内容：

    
        com.alibaba
        druid
        1.1.6
    

2.2配置类

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/test
jdbc.username=root
jdbc.password=xxxxxx

2.3配置文件

@Configuration //声明是配置类
@PropertySource("classpath:jdbc.properties")
public class JdbcConfig {
    @Value("${jdbc.url}")
    String url;
    @Value("${jdbc.driverClassName}")
    String driverClassName;
    @Value("${jdbc.username}")
    String username;
    @Value("${jdbc.password}")
    String password;
    @Bean
    public DataSource dataSource(){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(driverClassName);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        return dataSource;
    }
}

3.3Controller层

@RestController
public class HelloController {
    @Autowired
    private DataSource dataSource;
    @GetMapping("hello")
    public String hello(){
        System.out.println("dataSource"+dataSource);
        return "hello spring boot";
    }
}

三、连接数据库（方法二，相对简洁）

3.1配置类

3.2配置文件

@Configuration //声明是配置类
public class JdbcConfig {
    @Bean
    @ConfigurationProperties(prefix = "jdbc")
    public DataSource dataSource(){
          return new DruidDataSource();
    }
}

 四、连接数据库（方法三）

 4.1JdbcProperties

@ConfigurationProperties(prefix = "jdbc")
public class JdbcProperties {
    private String url;
    private String driverClassName;
    private String username;
    private String password;

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getDriverClassName() {
        return driverClassName;
    }

    public void setDriverClassName(String driverClassName) {
        this.driverClassName = driverClassName;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

4.2JdbcConfig

@Configuration //声明是配置类
@EnableConfigurationProperties(JdbcProperties.class)
public class JdbcConfig {

    @Bean
    public DataSource dataSource(JdbcProperties jdbc){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName(jdbc.getDriverClassName());
        dataSource.setUrl(jdbc.getUrl());
        dataSource.setUsername(jdbc.getUsername());
        dataSource.setPassword(jdbc.getPassword());
        return dataSource;
    }
}

五、配置多个yml文件

5.1yml文件

 

 5.2Controller层：

@RestController
public class HelloController {

    @Value("${duobaoyu.url}")
    private String yuUrl;
    @Value("${zhashutiao.url}")
    private String shutiaoUrl;
    @GetMapping("hello")

     public String hello(){
        System.out.println("duobaoyuurl="+yuUrl);
        System.out.println("shutiaourl="+shutiaoUrl);
        return "hello spring boot";
     }
}

六、用lombok插件获取get，set和toString方法

6.1安装插件

6.2导入pom坐标

       
            org.projectlombok
            lombok
        

6.3实体类

@Data
public class User {
    private Long id;
    // 用户名
    private String userName;
    // 密码
    private String password;
    // 姓名
    private String name;
    // 年龄
    private Integer age;
    // 性别，1男性，2女性
    private Integer sex;
    // 出生日期
    private Date birthday;
    // 创建时间
    private Date created;
    // 更新时间
    private Date updated;
    // 备注
    private String note;
    // getter和setter省略
}

加了@Data注解，实体类就无需添加get，set和toString方法，用的时候lombox插件会自动生成。

七、设置拦截器

@Slf4j
public class MyInterceptor implements HandlerInterceptor  {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        log.debug("这是MyInterceptor拦截器的preHandle方法");
        return HandlerInterceptor.super.preHandle(request, response, handler);
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        log.debug("这是MyIntercepor拦截器的postHandle方法");
        HandlerInterceptor.super.postHandle(request, response, handler, modelAndView);
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.debug("这是MyIntercepor拦截器的afterCompletion方法");
        HandlerInterceptor.super.afterCompletion(request, response, handler, ex);
    }
}

@Configuration
public class MvcConfig implements WebMvcConfigurer {

    
    @Bean
    public MyInterceptor myInterceptor(){
        return new MyInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry){
        registry.addInterceptor(myInterceptor()).addPathPatterns("/*");
    }
}

yml：

logging:
  level:
    com.bukaedu: debug
    org.springframework: info

八、查询操作

8.1配置文件

application.properties:

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/test
jdbc.username=root
jdbc.password=xxxxxx

application.yml:

spring:
  profiles:
    active: abc,def
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/test
    username: root
    password: xxxxxx
  redis:
    host: localhost
    port: 6379

server:
  port: 80
logging:
  level:
    com.bukaedu: debug
    org.springframework: info
mybatis:
  type-aliases-package: com.bukaedu.pojo
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

8.2pojo

@Data
@Table(name="tb_user")
public class User {
    @Id
    @KeySql(useGeneratedKeys = true)
    private Long id;
    // 用户名
    private String userName;
    // 密码
    private String password;
    // 姓名
    private String name;
    // 年龄
    private Integer age;
    // 性别，1男性，2女性
    private Integer sex;
    // 出生日期
    private Date birthday;
    // 创建时间
    private Date created;
    // 更新时间
    private Date updated;
    // 备注
    private String note;
    // getter和setter省略
}

8.3Mapper

public interface UserMapper extends Mapper {
}

8.4Service 

@Service
public class UserService {
    @Autowired
    private UserMapper userMapper;
    public User queryById(Long id){
        return userMapper.selectByPrimaryKey(id);

    }
    @Transactional
    public void savaUser(User user){
        userMapper.insertSelective(user);
        System.out.println("新增用户");
    }
}

8.5Controller

@RestController
public class HelloController {

   @Autowired
   private UserService userService;

   @GetMapping("/user/{id}")
     public User hello(@PathVariable Long id){
       return userService.queryById(id);
     }
}

8.6启动类

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

九、单元测试

@RunWith(SpringRunner.class)
@SpringBootTest
public class UserTest {
    @Autowired
    private UserService userService;
    @Test
    public void queryById(){
        User user=userService.queryById(1L);
        System.out.println("user="+user);
    }
    @Test
    public void saveUser(){
        User user=new User();
        user.setUserName("test");
        userService.savaUser(user);
    }
}