This is a question from Java Rule Round Up, the answer is NO. but I remember that static constructor is necessary for a singleton class but cannot find the document, if it is, then it is valid to have a static constructor though it is not very often used. Am I missing something here? Thanks, -Yan
Even when implementing a singleton pattern, the constructor is not static. Rather, the constructor is private. There is another method, which is static, often named "instance" or "singleton" that invokes the constructor. A constructor can never be static. Here's a sample of a class that implements the singleton pattern: