哈哈，终于被我搞成死锁了！

Aga

同时有两个线程同时访问这个servlet会导致一些问题：
第一个线程等待第二个的notify
而因为事物级别的提升导致第二个线程等待第一个线程的结束。
最终导致：死锁

public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {try {Class.forName("com.mysql.jdbc.Driver");Connection c = DriverManager.getConnection("jdbc:mysql://localhost/hibernate", "root", "19841230");c.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);c.setAutoCommit(false);Statement stmt = c.createStatement();ResultSet rs = stmt.executeQuery("select student.STUDENT_NAME " +"from student where student.STUDENT_NAME='FrenchMan' "); if(!rs.next()){synchronized(lock){if(i++%2==0){lock.wait();} else {lock.notify();}stmt.execute("insert into student(student_name) values('FrenchMan')");}}c.commit();rs.close();stmt.close();c.close();} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}