编写validation自定义注解：
@Target({ ElementType.FIELD, ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
@Document
@Constraint(validatedBy = { Brx.BrxValidator.class }) // validatedBy 需要ConstraintValidator的实现类
public @interface Brx {
//自定义方法：
String message() default "名称不存在";
Boolean required()default false；
//validate注解通用方法：
Class<?>[]groups() default {};
Class<? extends Payload>[]payload() default {}
public static final calss BrxValidator implements ConstraintValidator<Brx,String>{
private Boolean required = false;
public static final Pattern brx_pattern = Pattern.compile("brx");
@Override
public void initialize(Brx constraintAnnotation) {
this.requirde=constraintAnnotation.required();
}
@Override
public boolean isValid(String value, ConstraintValidatorContext context) { //value为比对值
if(this.required){
return brx_pattern.matcher(value).matches(); //定义校验规则
}
if(value=null||"".equals(value)){
return true;
}
return brx_pattern.matcher(value).matches();
}
}