表产生sequence功能，测试并发

	@Test
	public void testSerialNum() throws Exception{
	    final ConcurrentHashMap<String,Integer> map = new ConcurrentHashMap<String,Integer>(5000);
	    Vector<Thread> threads = new Vector<Thread>();
	    Thread r = new Thread() {
	        public void run() {
	            for (int i = 1; i <= 500; i++) {
	                String seqNo =   serialNum.getLocalNum("444", "t_acc_subject_occur_his", 10);
	                updateMap(map,seqNo,"r1");
	            }
	        }

	    };
	    threads.add(r);
	    Thread r1 = new Thread() {
	        public void run() {
	            for (int i = 1; i <= 500; i++) {
	                String seqNo =   serialNum.getLocalNum("444", "t_acc_subject_occur_his", 10);
	                updateMap(map,seqNo,"r2");
	            }
	        }
	        
	    };
	    threads.add(r1);
	    Thread r2 = new Thread() {
	        public void run() {
	            for (int i = 1; i <= 500; i++) {
	                String seqNo =   serialNum.getLocalNum("444", "t_acc_subject_occur_his1", 10);
	                updateMap(map,seqNo,"r3");
	            }
	        }
	        
	    };
	    threads.add(r2);
	    r.start();
	    r1.start();
	     r2.start();
	    for (Thread iThread : threads) {
	        try {
	            // 等待所有线程执行完毕
	            iThread.join();
	        } catch (InterruptedException e) {
	            e.printStackTrace();
	        }
	    }
	    for(String str:map.keySet()){
	        if(map.get(str)>1){
	            System.out.println(str+"================================================(((((((((((((((((((((((((((="+str+"---"+map.get(str));
	        }
	    }
	}
	
	public static synchronized  void updateMap(ConcurrentHashMap<String, Integer> map,String key,String id){
	    if(map.containsKey(key)){
	        Integer i = map.get(key);
	        map.put("", i+1);
	    }else{
	        map.put(key, 1);
	    }
	}