springboot学习代码

参考：https://gitee.com/CandyWall/spring-boot-study

• restful 风格
• yaml
• 整合 junit
• 整合 mybatis
• 整合 druid

restful 风格

1. @ResponseBody
2. @RequestParam
   详情：https://blog.csdn.net/sswqzx/article/details/84195043
3. @PathVariable
4. //@Controller
   //@ResponseBody
   @RestController
5. 可以将公有路由提取到类外面
6. 方法可以简写为 getmapping…

@Component
@Data
public class User {
    private Integer id;
    private String username;
    private String password;
}

@Controller
public class BookController {
    @RequestMapping(value = "/users1", method = RequestMethod.POST)
    @ResponseBody
    public String save() {
        System.out.println("user1 save...");
        return "{'module':'user1 save'}";
    }
    @RequestMapping(value = "/users1/{id}", method = RequestMethod.DELETE)
    @ResponseBody
    public String delete(@PathVariable Integer id) {
        System.out.println("user1 delete..." + id);
        return "{'module':'user1 delete'}";
    }

    @RequestMapping(value = "/users1", method = RequestMethod.PUT)
    @ResponseBody
    public String update(@RequestBody User user) {
        System.out.println("user1 update..." + user);
        return "{'module':'user1 update'}";
    }

    @RequestMapping(value = "/users1/{id}", method = RequestMethod.GET)
    @ResponseBody
    public String getById(@PathVariable Integer id) {
        System.out.println("user1 getById..." + id);
        return "{'module':'user1 getById'}";
    }

    @RequestMapping(value = "/users1", method = RequestMethod.GET)
    @ResponseBody
    public String getAll() {
        System.out.println("user1 getAll...");
        return "{'module':'user1 getAll'}";
    }
}

简化

//@Controller
//@ResponseBody
@RestController
@RequestMapping("/users2")
public class BookController {
    //@RequestMapping(method = RequestMethod.POST)
    @PostMapping
    public String save(@RequestBody User user) {
        System.out.println("user2 save..." + user);
        return "{'module':'user2 save'}";
    }

    //@RequestMapping(value = "/{id}", method = RequestMethod.DELETE)
    @DeleteMapping("/{id}")
    public String delete(@PathVariable Integer id) {
        System.out.println("user2 delete..." + id);
        return "{'module':'user2 delete'}";
    }

    //@RequestMapping(method = RequestMethod.PUT)
    @PutMapping
    public String update(@RequestBody User user) {
        System.out.println("user2 update..." + user);
        return "{'module':'user2 update'}";
    }

    //@RequestMapping(value = "/{id}", method = RequestMethod.GET)
    @GetMapping("/{id}")
    public String getById(@PathVariable Integer id) {
        System.out.println("user2 getById..." + id);
        return "{'module':'user2 getById'}";
    }

    //@RequestMapping(method = RequestMethod.GET)
    @GetMapping
    public String getAll() {
        System.out.println("user2 getAll...");
        return "{'module':'user2 getAll'}";
    }
}

yaml

1. application.yml

country: China
province: Beijing
city: Beijing
area: Haidian

party: true

birthday: 1949-10-01

user:
  name: zhangsan
  age: 17

user2:
  name: lisi
  age: 18

a:
  b:
    c:
      d:
        e: 123

habits:
  - game
  - music
  - sleep

habits2: [game, music, sleep]

users:
  - name: zhangsan
    age: 40
  - name: lisi
    age: 38
  - name: wangwu
    age: 15

users2:
  -
    name: zhangsan
    age: 40
  -
    name: lisi
    age: 38
  -
    name: wangwu
    age: 15

users3: [{name: zhangsan, age: 40}, {name: lisi, age: 38}, {name: wangwu, age: 15}]

baseDir: C:\windows

tempDir: ${baseDir}\temp

tempDir1: "${baseDir}\temp"

datasource:
  driver: com.mysql.jdbc.Driver
  url: jdbc:mysql://localhost:3306/springboot_db
  username: root
  password: 123

2. MyDataSource.java

@ConfigurationProperties(prefix = "datasource")
@Component
@Data
public class MyDataSource {
    private String driver;
    private String url;
    private String username;
    private String password;
}

3. 数据显示

@RestController
@RequestMapping("/books")
public class BookController {
    // 读取yaml数据中的单一数据
    @Value("${country}")
    private String country1;

    @Value("${user.name}")
    private String name1;

    @Value("${user2.name}")
    private String name2;

    @Value("${habits[1]}")
    private String habit;

    @Value("${users[1].age}")
    private Integer age;

    @Value("${tempDir}")
    private String tempDir;

    @Value("${tempDir1}")
    private String tempDir1;

    // 使用自动装配将所有的数据封装到Environment对象中
    @Autowired
    private Environment env;

    @Autowired
    private MyDataSource dataSource;

    @GetMapping
    public String getById() {
        System.out.println("springboot is running...");
        System.out.println("country1 = " + country1);
        System.out.println("name1 = " + name1);
        System.out.println("name2 = " + name2);
        System.out.println("habit = " + habit);
        System.out.println("age = " + age);
        System.out.println("tempDir = " + tempDir);
        System.out.println("tempDir1 = " + tempDir1);
        System.out.println("====================================");
        System.out.println("country1 = " + env.getProperty("country"));
        System.out.println("name1 = " + env.getProperty("user.name"));
        System.out.println("name2 = " + env.getProperty("user2.name"));
        System.out.println("habit = " + env.getProperty("habits[1]"));
        System.out.println("age = " + env.getProperty("users[1].age"));
        System.out.println("tempDir = " + env.getProperty("tempDir"));
        System.out.println("tempDir1 = " + env.getProperty("tempDir1"));
        System.out.println("=====================================");
        System.out.println("dataSource = " + dataSource);
        return "springboot is running...";
    }
}

整合 junit

1. 创建模块，不勾选任何选项
2. BookDao 接口

public interface BookDao {
    public void save();
}

3. BookDaoImpl 类

@Repository
public class BookDaoImpl implements BookDao {
    @Override
    public void save(){
        System.out.println("bookDao is running...");
    }
}

4. 测试

// 如果测试类跟springboot运行引导类不在同一个包下，那么需要给@SpringBootTest注解加classes属性
@SpringBootTest(classes = Demo1Application.class)
class Demo1ApplicationTests {

    // 1、注入要测试的对象
    @Autowired
    private BookDao bookDao;

    @Test
    void contextLoads() {
        // 2、执行要测试的对象对应的方法
        bookDao.save();
    }


}

整合 mybatis

1. 导入模块选择对应的技术：
   SQL 中的 MyBatis Framwork 和 MySQL Driver
2. application.yml 配置数据库信息

# 配置数据信息
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/test1
    username: root
    password: xxx

3. domain.Book.java

@Component
@Data
public class Book {
    private String username;
    private String password;
    private Integer age;
}

4. 接口：dao.BookDao

@Mapper
public interface BookDao {
    @Select("select * from users where age = #{age}")
    Book getByAge(Integer age);
}

5. 测试：

@SpringBootTest
class Demo2ApplicationTests {
    @Autowired
    private BookDao bookDao;

    @Test
    void contextLoads() {
        System.out.println(bookDao.getByAge(11));
    }

}

整合 druid