3ab84b087a
This patch changes the way that the ConnectivityThread is lazily instantiated by using the "lazy initialization holder class idiom". The first code point that tries to obtain a reference to the unique ConnectivityThread instance will trigger the creation of the Singleton class, which will guarantee a thread-safe initialization of the static INSTANCE field inside Singleton according to the language specs. This is the Item #71 of Effective Java. The unique static instance of ConnectivityThread is not stored directly inside ConnectivityThread class but is stored in a static nested class. This is to avoid triggering the creation of that unique instance when Zygote does class preloading at phone startup. Otherwise this would lead to Zygote creating a new OS thread during preloading, which is a fatal error. Test: frameworks-wifi tests pass Bug: 26749700 Bug: 28537383 Bug: 32130437 Change-Id: I4d5672a3195d3af9a0a2c85f871695257abe782b