code: public static SynchronizedInterner<Object> setGlobal(Interner<Object> delegate) {
      synchronized(globalMutex) {
        SynchronizedInterner<Object> oldInterner = SynchronizedInterner.interner;
        SynchronizedInterner.interner = Generics.newSynchronizedInterner(delegate);
        return oldInterner;
      }
    }
docs: For supplying a new instance for the global methods to use.
  
  @return the previous global interner.