如果您尝试在OrderFulfillment中覆盖object . equals方法，从而其“等于”其Order，您就打破了Object . equals的合同，其指定相等必须是对称的。

If you try to override the Object.equals method in OrderFulfillment such that it is "equal" to its Order, you've broken the contract of Object.equals, which specifies that equality must be symmetric.

youdao

本文定义了模糊关系的自反闭包、对称闭包概念，同时给出了模糊关系的自反闭包、对称闭包的运算方法及性质。 打破了在原有的模糊关系只有传递闭包的局面。

This paper gives a new concept of reflexive closure of fuzzy relation and symmetric closure of fuzzy relation, and also gives operation method and properties about it.

youdao