The singleton is a useful design pattern for allowing only one instance of your class, but common mistakes can inadvertently allow more than one instance to be created.

单例模式是一种非常有用的设计模式，它允许你的类对外只提供一个实例，但是常犯的错误在于不止一个实例被创建。

youdao

Notice what our code has so far: first, our Account class isn't a bean (it essentially has a getter -- but no setter -- for its one data member).

注意一下目前我们的代码有哪些东西：首先，我们的 Account 类不是一个 bean （实际上，对于它的一个数据成员它有一个getter方法――但是没有 setter 方法）。

youdao

Xanax is one of a class of drugs known colloquially as "benzos" (benzodiazepines) that are safe and highly effective - but can also be addictive and have potential for abuse.

阿普唑仑是一类俗称“苯二氮平”的药物。这类药物安全有效，但是也可能让人上瘾并被滥用。

youdao

but that class got filled up, because I had a late Phase One for example, and so.

但是那个课已经被选满了，因为我在第一阶段选晚了。

关于授课系统 - SpeakingMax英语口语达人

But for one class of investor, the mortgage pay-down is a clear winner.

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She agreed to plan the parties for one class but then also committed to taking on a fund-raiser.

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Vauvert Primary is currently oversubscribed for September if it continues to operate two reception classes, and numbers registered at La Houguette are high for one reception class but too low to support two classes.

BBC: Alan Brown