/**
	 * 自動生成編號格式：yyMM+四位流水號
	 */
	@RequestMapping(params = "createCode")
	@ResponseBody
	public AjaxJson createCode(HttpServletRequest request, String tableName,
			String fieldName) {
		AjaxJson j = new AjaxJson();

		String sql = "select Max(a." + fieldName + ") max_code from "
				+ tableName + " a ";

		List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
		list = jdbcTemplate.queryForList(sql);
		// System.out.println("最大編號："+list.get(0).get("max_comment_code"));
		String comment_code = ""; 
		String max_code = "";
		if (list.size() > 0) {
			max_code = (String) list.get(0).get("max_code");
		}

		SimpleDateFormat format = new SimpleDateFormat("yyMM"); // 時間字串產生方式
		String uid_pfix = format.format(new Date()); // 組合流水號前一部分，時間字串，如：1601
		System.out.println("time=" + format.format(new Date()));
		if (max_code != null && max_code.contains(uid_pfix)) {
			String uid_end = max_code.substring(4, 8); // 擷取字串最後四位，結果:0001
			// System.out.println("uid_end=" + uid_end);
			int endNum = Integer.parseInt(uid_end); // 把String型別的0001轉化為int型別的1
			// System.out.println("endNum=" + endNum);
			int tmpNum = 10000 + endNum + 1; // 結果10002
			// System.out.println("tmpNum=" + tmpNum);
			comment_code = uid_pfix + UtilMethod.subStr("" + tmpNum, 1);// 把10002首位的1去掉，再拼成1601260002字串
		} else {
			comment_code = uid_pfix + "0001";
		}
		// System.out.println(comment_code);

		Map<String, Object> map = new HashMap<String, Object>();
		map.put("msg", comment_code);
		j.setAttributes(map);
		return j;
	}

//公共方法
public class UtilMethod {
	
	
	 /*
	  * 把10002首位的1去掉的實現方法：
	  * @param str
	  * @param start
	  * @return
	  */
	 public static String subStr(String str, int start) {
	        if (str == null || str.equals("") || str.length() == 0)
	            return "";
	        if (start < str.length()) {
	            return str.substring(start);
	        } else {
	            return "";
	        }

	    }
}
 

前端：

//自動生成編號；格式：yyMM0001
function createCode() {
    var id = $("[name='id']").val();
    // alert(id.length);
     if(id.length<=0){
	  var a="";
	  $.ajax({
					async : false,
					cache : false,
					type : 'POST',
					contentType : 'application/json', 
					dataType:"json",
					url : "Controller.do?createCode&tableName=表名&fieldName=欄位名",
					error : function() {
						alert('出錯了');
						frameElement.api.close();
					},
					success : function(data) {
						a=data.attributes.msg;
					} 
					
	}); 
//alert(a);
        $("#check_task_code").val(a);
     }
  }