Singleton Examples from the Java API

10 months ago • 0

The examples from the Java API for the Singleton design pattern mention:
java.lang.Runtime#getRuntime()
java.awt.Desktop#getDesktop()
java.lang.System#getSecurityManager()

I don't understand the 3rd example.
System has a private constructor but no point of access.
SecurityManager has a public constructor.
Therefore neither are Singletons. Right?