动态获取当前时间，查询数据。

 1 HashMap<String,Object> paramMap =new HashMap<String,Object>();
 2             //获取当前时间
 3             SimpleDateFormat timesystem = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
 4             Date date = new Date();
 5             
 6             String createDate = timesystem.format(date);
 7             paramMap.put("createDate", createDate);
 8             
 9             //获取当前月，确定表名
10             SimpleDateFormat getmonth = new SimpleDateFormat("M");
11             String month = getmonth.format(date);
12             paramMap.put("month", month);
13             
14             //将当前时间减上一天，做条件查询
15             Calendar calendar =Calendar.getInstance();
16             calendar.setTime(date);
17             calendar.set(Calendar.DATE, calendar.get(Calendar.DATE)-1);
18             date= calendar.getTime();
19             String beforetime = timesystem.format(date);
20             paramMap.put("beforetime", beforetime);
21             return this.thirdAPIService.listdhHistoryRoom(paramMap);
22         }

 1  <select id="selectDhRoomHistory" parameterType="java.util.HashMap" resultType="java.util.LinkedHashMap">
 2         <![CDATA[
 3             select * from dh_room_history_${month} 
 4         ]]>
 5         <where>
 6         <if test ="beforetime != null">
 7             <![CDATA[ and createDate >= #{beforetime} ]]>
 8         </if>
 9         <if test ="createDate != null">
10              <![CDATA[ and createDate <= #{createDate} ]]>
11         </if>
12         </where>
13      </select>