Json Spring MVC PATCH 方法：部分更新

我有一个项目，我正在使用Spring MVC+Jackson构建REST服务.假设我有以下java实体

public class MyEntity {
    private Integer id;
    private boolean aBoolean;
    private String aVeryBigString;
    //getter & setters
}

Sometimes, I just want to update the boolean value, and I don't think that sending the whole object with its big string is a good idea just to update a simple boolean. So, I have considered using the PATCH HTTP method to only send the fields that need to be updated. So, I declare the following method in my controller:

@RequestMapping(method = RequestMethod.PATCH)
public void patch(@RequestBody MyVariable myVariable) {
    //calling a service to update the entity
}

The problem is: how do I know which fields need to be updated? For instance, if the client just wants to update the boolean, I will get an object with an empty "aVeryBigString". How am I supposed to know that the user just wants to update the boolean, but does not want to empty the string?

I have "solved" the problem by building custom URLs. For instance, the following URL: POST /myentities/1/aboolean/true will be mapped to a method that allows to only update the boolean. The problem with this solution is that it is not REST compliant. I don't want to be 100% REST compliant, but I do not feel comfortable with providing a custom URL to update each field (especially given that it causes problems when I want to update several fields).

另一个解决方案是将"MyEntity"拆分为多个资源，只更新这些资源，但我觉得这没有意义:"MyEntity"is是一个普通的资源，而不是composed of个其他资源.

那么，有没有一种优雅的方法来解决这个问题呢？