1.rest風格

[email protected]註解

2.1配置正則例項

@AllArgsConstructor
@NoArgsConstructor
@Data
@Accessors(chain = true)  //lombok
public class User implements Serializable {
    private  String  name;
}

@RestController   //responsebody +controller
public class UserController {
    @GetMapping("/user/{name:.*}")   
    public User  testUser(@PathVariable(required = false,value = "name") User user){
        System.out.println(user.getClass());
        return  user;
    }
}

@SpringBootApplication
public class MvcDemoApplication  {

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

@Configuration
@ComponentScan(value = "springmvc.demo")//掃描包
public class MVCConfig  {

}

spring.http.encoding.charset=UTF-8  #處理編碼
spring.http.encoding.force=true
spring.http.encoding.enabled=true
server.tomcat.uri-encoding=UTF-8

[email protected]與@Validated

@valid與@Validated的區別，@Validated是spring中的，是在@valid基礎上而來的，在@valid的基礎上增加分組功能，這裡就直接說@Validated，沒有加分組都需要認證，加了分組只有符合分組的才需要認證，一般不使用分組

3.1基本使用

@AllArgsConstructor
@NoArgsConstructor
@Data
@Accessors(chain = true)
public class User implements Serializable {
    @NotNull(message="不能為空")//含有屬性groups
    private  String  name;
}

@RestController
public class UserController {
    @GetMapping("/user")
    public User  testUser(@Validated User user, BindingResult  result){
        result.getAllErrors().stream().forEach((x)->{
            System.out.println(x.getObjectName()+":"+x.getDefaultMessage());
        });
        System.out.println(user.getClass());
        return  user;
    }
}

輸出結果：user:不能為空

備註：假如沒有BindingResult result，那麼在進入testUser之前就會被攔截，message="不能為空"並沒有什麼作用，加入BindingResult result之後，才會進入testUser方法，在沒有進入方法時的異常頁面見後該篇4

3.2自定義符合valid的註解

這裡定義的是@NoNull註解

//會自動載入，不需要其他的配置
public class MyValidAnnotation implements ConstraintValidator<MyNotNull,Object> {
    /*
    obj:需要驗證的引數
     */
    @Override
    public boolean isValid(Object obj, ConstraintValidatorContext constraintValidatorContext) {
        System.out.println(obj);
        return false;
    }

    @Override
    public void initialize(MyNotNull constraintAnnotation) {

    }
}

@Target({ElementType.METHOD, ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
@Constraint(validatedBy =MyValidAnnotation.class )
public @interface MyNotNull {
    String message() default "{javax.validation.constraints.NotNull.message}";
    Class<?>[] groups() default {};
    Class<? extends Payload>[] payload() default {};
}

@AllArgsConstructor
@NoArgsConstructor
@Data
@Accessors(chain = true)
public class User implements Serializable {
    @MyNotNull(message="不能為空---MyNotNull")
    private  String  name;
}

@RestController
public class UserController {
    @GetMapping("/user")
    public User  testUser(@Validated User user, BindingResult  result){
        result.getAllErrors().stream().forEach((x)->{
            System.out.println(x.getObjectName()+":"+x.getDefaultMessage());
        });
        return  user;
    }
}

4.異常訊息的處理

4.1驗證異常訊息的處理上述已經說明

4.2直接被攔截的異常處理

springboot會相應的轉向我們在resources下新建的resources的error的相應的錯誤程式碼的頁面

還可以是如下這樣，表示以4開頭的錯誤頁面

4.3執行過程中出現的異常

4.3.1直接丟擲異常

@GetMapping("/user/error")
    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {
        throw  new Exception("出錯了");
    }

4.3.2 throw自定義異常類

@ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "內部出錯了！")
public class MyException extends RuntimeException {
}

 @GetMapping("/user/error")
    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {
        throw  new MyException();
    }

4.3.3 使用@ExceptionHandler註解

  @ResponseBody
    @GetMapping("/testExceptionHandler")
    public User  testUser1(@Validated User user, BindingResult  result) throws Exception {
        int  i=10/0;
        return user;
    }

@ExceptionHandler({Exception.class})
    public String  testExceptionHandler(){
        return   "redirect:/error.html"; //重定向
    }

 4.3.4 修改狀態碼及原因，@ResponseStatus也能在

　　 @ExceptionHandler({Exception.class})
    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "內部錯誤")
    public void  testExceptionHandler(){
    }

 備註：這樣之後不會去相應的頁面，也就是加入有返回值例如return "redirect:/error.html";，會失效

[email protected]定製全域性的異常，類中的@ExceptionHandler優先順序高於@ControllerAdvice中的@ExceptionHandler優先順序

@ControllerAdvice
public class MyExceptionHandler {
    @ExceptionHandler({Exception.class})
    @ResponseStatus(value = HttpStatus.INTERNAL_SERVER_ERROR,reason = "內部錯誤")
    public void  testExceptionHandler(){
    }
}

5.jsonview