java - 比较任意两个Java对象的常用方法

Question

我想比较两个 Java 对象而不覆盖 equals 方法。由于我需要重写我拥有的 n 个类中的 equals 方法，因此我需要一个通用的实用方法来比较两个 Java 对象。

类似的东西:

A a1,a2;
B b1,b2;
C c1,c2;
-----
-----
boolean isEqual1 = new ObjectComparator().isEquals(a1 , a2);
boolean isEqual2 = new ObjectComparator().isEquals(b1 , b2);
boolean isEqual3 = new ObjectComparator().isEquals(c1 , c2);

请帮我写一个比较任何 Java 对象的通用工具

希望通过Field类，和getClass方法来实现。请指导我。

Answer 1

看看EqualsBuilder.reflectionEquals在 Apache Commons 库中。

来自documentation :

This method uses reflection to determine if the two Objects are equal.

It uses AccessibleObject.setAccessible to gain access to private fields. This means that it will throw a security exception if run under a security manager, if the permissions are not set up correctly. It is also not as efficient as testing explicitly.

---

因此，在您的示例中，它看起来像:

A a1,a2;
B b1,b2;
C c1,c2;
-----
-----
boolean isEqual1 = EqualsBuilder.reflectionEquals(a1 , a2);
boolean isEqual2 = EqualsBuilder.reflectionEquals(b1 , b2);
boolean isEqual3 = EqualsBuilder.reflectionEquals(c1 , c2);