The line annotated in red is where biased locking is enabled.

红色的行是偏向锁被激活的地方。

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If the lock happens to be accessed by only one thread, biased locking can be applied.

如果锁刚好只被一个线程访问，则可以使用偏向锁。

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Whether or not biased locking is being performed (-xx: + UseBiasedLocking); note that JDK 1.6 + automatically does this.

是否执行偏向锁(biased locking，- XX： + UseBiasedLocking)；注意，JD k 1.6及更高版本会自动执行这个特性。

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