Regular Expression objects store patterns used to search strings for character combinations.

正则表达式对象存储用于搜索字符组合的字符串的模式。

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With the exception of enumerators, all regular expression classes are thread safe or can be converted into thread-safe objects by a synchronized method.

除枚举数之外，所有正则表达式类都是线程安全的或者可以通过同步方法转换成线程安全对象。

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