创建springBoot项目
通过IDEA的Spring Initializr创建springBoot项目
一、三种启动方式
1.DemoApplication.java启动类 -> 打开 -> 右击 -> run DemoApplication
2.项目根目录 -> mvn spring-boot:run
3.mvn install -> java -jar demo_0.0.1_snapshot.jar
二、springBoot配置文件
application.properties 或者 application.yml (注意yml键值间要空格)
application.properties
--|server.port=8081
--|server.context-path=/demo
application.yml
--|server
----|port: 8081
----|context-path: /demo
三、项目属性配置 @Value @Component @ConfigurationProperties
3.1yml配置文件-值读取
application.yml
cupSize: B
age: 18
content： "cupSize: ${cupSize}, age: ${age}" #获取yml属性值
3.2通过类获取yml配置文件属性值
@RestController
public class Demo{
@value("${cupSize}")
private String cupSize; //获取yml属性值
@value("${age}")
private Integer age;
@value("${content}")
private String content;
@RequestMapping(value="/say" method = RequestMethod.GET)
public void say(){
return content;
}
}
3.3配置文件属性值对象化
application.yml
girl:
cupSize: B
age: 18
/**
*需要注入 @Component
**/
@Component
@ConfigurationProperties("prefix="girl")
public class GirlProperties{
private String cupSize;
private Integer age;
//相应get和set省略
}
四、controller的使用
@Controller 处理http请求。 配合模板使用，使用模板带来性能吮耗，所以不推荐使用。
@RestController Spring4之后新加注解，原来返回json需要@ResponseBody配合@Controller
@RequestMapping 配置url映射
4.1@RestController 和 @RequestMapping配置两个url映射
@RestController
public class HelloController{
@RequestMapping(value={"hello","hi"} method=RequestMethod.GET)
public void say(){
return girlProperties.getCupSize();
}
}
4.2@RequestMapping给整个类配置url映射
@RestController
@RequestMapping("/hello")
public class HelloController{
@RequestMapping(value="/say" method=RequestMethod.GET)
public String say(){
return girlProperties.getCupSize();
}
}
访问： localhost:8080/hello/say
4.3获取请求参数
@PathVariable 获取url中数据
@RequestParam 获取请求参数值
@GetMapping 组合注解
4.3.1@PathVariable实例
@RestController
@RequestMapping("/hello")
public class HelloController{
@RequestMapping(value="/say/{id}" method=RequestMethod.GET)
public String say(@PathVariable("id") Integer id){
return "id"+id;
}
}
4.3.2@RequestParam实例
@RestController
@RequestMapping("/hello")
public class HelloController{
@RequestMapping(value="/say" method=RequestMethod.GET)
public String say(@RequestParam(value="id",defaultValue="0") Integer myId){
return "id"+myId;
}
}
访问：localhost:8080/hello/say?id=100
4.4@GetMaping和@PostMaping简化注解写法
@RestController
@RequestMapping("/hello")
public class HelloController{
@GetMapping("/say") //等同于： @RequestMapping(value="/say" method=RequestMethod.GET)
public String say(@RequestParam(value="id",defaultValue="0") Integer myId){
return "id"+myId;
}
}
五、数据库操作
5.1Spring-Data-Jpa : springBoot对hibernate整合
5.2数据库配置和JPA配置:application.yml
spring:
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/dbgirl
username: root
password: 123456
jpa:
hebernate:
ddl-auto: create
show-sql: true
5.3数据库操作
接口：
public interface GirlRepository extends JpaRepository<Girl,Integer>{
//扩展接口-以年龄查询
public List<Girl> findByAge(Integer age);
}
类：
@RestController
public class GirlController{
@Autowired
private GirlRepository girlRepository ;
/**
*查询表全部记录
*/
@GetMapping(value="/girls")
public List<Girl> girlList(){
return girlRepository.findAll();
}
/**
*添加一条记录
*/
@PostMapping(value="/girls")
public List<Girl> girlAdd(@RequestParam("cupSize")String cupSize,@RequestParam("age")String age){
Girl girl = new Girl();
girl.setCupSize(cupSize);
girl.setAge(age);
return girlRepository.save(girl);
}
//查询一条记录
@GetMapping(value="girls/{id}")
public Girl girlFindOne(@PathVariable("id") Integer id){
return girlRepository.findOne(id);
}
//更新
@PutMapping(value="girls/{id}")
public Girl girlFindOne(@PathVariable("id") Integer id，
@RequestParam("cupSize") Integer cupSize){
Girl girl = new Girl();
girl.setId(id);
girl.setCupSize(cupSize);
return girlRepository.save(girl);
}
//删除
@DeleteMapping(value="girls/{id}")
public Girl girlDelete(@PathVariable("id") Integer id){
return girlRepository.delete(id);
}
}
六、事物管理
事物管理@Transactional
Service类：
@Service
pubic class GirlService{
@Autowired
private GirlRepository girlRepository;
@Transactional
public void insertTwo(){
Girl girlA = new Girl();
girlA.setCupSize("A");
girlA.setAge(18);
girlRepository.save(girlA);
Girl girlB = new Girl();
girlB.setCupSize("B");
girlB.setAge(19);
girlRepository.save(girlB);
}
}
Controller类：
@RestController
public class GirlController{
@PostMapping
public void girlTwo(){
girlService.insertTwo();
}
}