类级别的注解可以用来定义哪些种类的方法可以被auto-delection

auto-detection表示使用命名习惯或签名模版来查找方法用来数据绑定。例如，被称为"getters"的方法可以通过寻找返回一个值，没有任何参数且具有前缀get在方法名的public的成员方法来auto-detected,

伪值NONE表示所有的auto-detection对于指定的类被禁用，并且注解也适用于其子类，但是仅当解析该类时才有效)。

Pseudo-value ALWAYS表示auto-detection适用于所有的方法类型

默认的值是ALWAYS:这表示，默认的，auto-detection被启用适用于所有的类除非被指示别的

自1.5版本之后，可以使用细粒度的定义，to basically define minimum visibility level needed。Defaults are different for different types(getters需要是public; setters可以是任何访问修饰符，例如)

@Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE}
@Retention(RetentionPolicy.RUNTIME)
@JacksonAnnotation
public @interface JsonAutoDetect{

    public enum Visibility{
        /*
          Value that means that all kinds of access modifiers are acceptable,
          from private to public
        */
        ANY,
        /*
          Value that means that any other access modifier other than 'private'
          is considered auto-detectable.
        */
        NON_PRIVATE,
        /*
          Value that means access modifiers 'protected' and 'public' are auto-detectable
          (and 'private' and 'package access' == no modifiers are not)
        */
        PROTECTED_AND_PUBLIC,
        /*
          Value to indicate that only 'public' access modifier is considered auto-detectable.
        */
        PUBLIC_ONLY,
        /*
          Value that indicates that no access modifiers are auto-detectable:
          this can be used to explicitly disable auto-detection for specified types.
        */
        NONE,
        /*
          Value that indicates that default visibility level(whatever it is,  depends on context)
          is to be used.This usually means that inherited value(from parent visibility settings) is
          to be used.
        */
        DEFAULT;

        public boolean isVisible(Member m){
            switch(this){
                case ANY:
                    return true;
                case NONE:
                    return false;
                case NON_PRIVATE:
                    return !Modifier.isPrivate(m.getMoeifiers());
                    // fall through to public case:
                case PUBLIC_ONLY:
                    return Modifier.isPublic(m.getModifiers());
                default:
                    return false;
            }
        }
    }

    Visibility getterVisibility() default Visibility.DEFAULT;
    Visibility isGetterVisibility() default Visibility.DEFAULT;
    Visibility setterVisibility() default Visibility.DEFAULT;
    Visibility creatorVisibility() default Visibility.DEFAULT;
    Visibility fieldVisibility() default Visibility.DEFAULT;
}