This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Except toString() method all other operations will create a new object ( except s=s+"47" will make 2). For scjp level this is correct (as there are little more to this with regards to the String constants as they may have created already before the method invoked, at the class loading).