是的.它扩展了Random，它总是具有事实线程安全的实现，并且从

Yes, it is. It extends Random, which always had a de facto threadsafe implementation, and, from Java 7, explicitly guarantees threadsafety.

如果许多线程使用单个SecureRandom，则可能存在争用，从而影响性能.另一方面，初始化SecureRandom实例可能相对较慢.共享全局RNG还是为每个线程创建一个新的RNG取决于您的应用程序. ThreadLocalRandom 类可能是用作模式以提供支持SecureRandom的解决方案.

If many threads are using a single SecureRandom, there might be contention that hurts performance. On the other hand, initializing a SecureRandom instance can be relatively slow. Whether it is best to share a global RNG, or to create a new one for each thread will depend on your application. The ThreadLocalRandom class could be used as a pattern to provide a solution that supports SecureRandom.