Since Domain components are represented by interfaces and not by classes, you can use multiple inheritance to combine several previously defined components into a new one.

由于域组件是通过接口展现而不是通过类，你可以用多继承来组合几个之前定义的组件成一个新的组件。

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Among the three leading contenders in the ease of use category, dom4j differs from the others in using an interface-based approach with multiple layers of inheritance.

就使用方便这一范畴而言，在JDOM、dom4j和electric XML这三个主要竞争者中，dom 4 j与其它两个的区别在于它使用带有多个继承层的基于接口的方法。

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