Java 코드에서 Singleton 패턴을 구현한 Connection 클래스가 있다. conn1, conn2, conn3이 모두 같은 인스턴스를 참조하며, 각각 count()를 호출한다.

class Connection {
    private static Connection _inst = null;
    private int count = 0;
    static public Connection get() {
        if(_inst == null) {
            _inst = new Connection();
            return _inst;
        }
        return _inst;
    }
    public void count() { count++; }
    public int getCount() { return count; }
}
public class main {
    public static void main(String[] args) {
        Connection conn1 = Connection.get();
        conn1.count();
        Connection conn2 = Connection.get();
        conn2.count();
        Connection conn3 = Connection.get();
        conn3.count();
        conn1.count();
        System.out.print(conn1.getCount());
    }
}