有时要为每一篇文章统计其点击次数,如果每一次浏览都要更新一次库的话,那性能在访问量很大的情况下,服务器的压力就会很大了,比较好一点的方法就是先将要更新的数据缓存起来,然后每隔一段时间再利用数据库的批量处理,批量更新库。源码如下: &7s.`
yf,z$CR
CountBean.java ^B^9KEjTz
}6ldjCT/,
/* Vjpy~iP4B
* CountData.java n=q76W\
* 7xR\kL.,
* Created on 2007年1月1日, 下午4:44 G#$-1"!`
* _yT Ed"$
* To change this template, choose Tools | Options and locate the template under !<F3d`a
* the Source Creation and Management node. Right-click the template and choose fV~[;e;U.
* Open. You can then make changes to the template in the Source Editor. Iu6
*/ !
dgNtI@
1Z&(6cDY8M
package com.tot.count; W*Y/l~x}
$:^td/p J
/** Ho]su?
* ;AG()NjOO:
* @author w!XD/jN
*/ W@esITr
public class CountBean { +w~oH =
private String countType; Uw:"n]G]D?
int countId; 0+8e,
/** Creates a new instance of CountData */ |vC~HJpuv'
public CountBean() {} E" vS $
public void setCountType(String countTypes){ 2KZneS`
this.countType=countTypes; 1 -b_~DF
} %l%HHT
public void setCountId(int countIds){ K)P%;X
this.countId=countIds; !@"OB~
} rZpXPI
public String getCountType(){ QsW/X0YBv
return countType; %}T6]S)%u
} H;"4C8K7
public int getCountId(){ !`r$"}g
return countId; ajpXL
} 8?C5L8)
} w2'5#`m
5-A\9UC*@
CountCache.java &nK<:^n
qJw_
/* y_[vr:s5pG
* CountCache.java I`#JwMU;m
* J~- 4C)
* Created on 2007年1月1日, 下午5:01
AOx[
* S8gs-gL#Og
* To change this template, choose Tools | Options and locate the template under t`QENXA}
* the Source Creation and Management node. Right-click the template and choose Xnh8e
* Open. You can then make changes to the template in the Source Editor. K<J9~
*/ =BrRYA
>R=|Wo`Ri
package com.tot.count; wKHBAW[i]
import java.util.*; fXB0j;A
/** `F6C-
* tf G@&&%9
* @author fc@A0Hf
*/ 13wE"-
public class CountCache { 048kPXm`
public static LinkedList list=new LinkedList(); XX~,>Q}H=
/** Creates a new instance of CountCache */ M^I(OuRMeI
public CountCache() {} wyG;8I
public static void add(CountBean cb){ :Tq~8!s
if(cb!=null){ nRY5xRvK
list.add(cb); :hA#m[
} XfmwVjy
} nj4/#W
} i mM_H;-X
eDB ;cN
CountControl.java -{A<.a3P}=
K|@G t%Y
/* 2Rz
* CountThread.java QS j]ZA
* xezcAwW
* Created on 2007年1月1日, 下午4:57 %>s|j'{
* azU"G(6y?+
* To change this template, choose Tools | Options and locate the template under Y^]rMK/;
* the Source Creation and Management node. Right-click the template and choose O
H7FkR
* Open. You can then make changes to the template in the Source Editor. .p$(ZH =~
*/ K+iP6B
y> (w\K9W
package com.tot.count; 8>%hz$no=
import tot.db.DBUtils; H[|~/0?K
import java.sql.*; d!{r v
/** Dhv3jg;lq
* B1Oq!k
* @author -^wl>}#*T3
*/ =Runf
+}
public class CountControl{ |&jXp%4T
private static long lastExecuteTime=0;//上次更新时间 w=@Dv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YoE3<[KD(
/** Creates a new instance of CountThread */ ]R? 4{t4
public CountControl() {} O9p|a%o
public synchronized void executeUpdate(){ F5#YOck&,
Connection conn=null; &?RQZHtg
PreparedStatement ps=null; "h ^Z
try{ aN=B]{!
conn = DBUtils.getConnection(); 2BobH_H
conn.setAutoCommit(false); J-4:H
gx
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b>$S<td
for(int i=0;i<CountCache.list.size();i++){ IM+o.@f-
CountBean cb=(CountBean)CountCache.list.getFirst(); LIdF 0
CountCache.list.removeFirst(); h1(4Ic
ps.setInt(1, cb.getCountId()); Np)lIGE
ps.executeUpdate();⑴ :i7;w%B
//ps.addBatch();⑵ ]N[ 5q=A5
} )_NO4`ejs/
//int [] counts = ps.executeBatch();⑶ Q7A MRrN
conn.commit(); Vq2$'lY
}catch(Exception e){ ;=UsAB]
e.printStackTrace(); -%dCw6aX+
} finally{ {_dvx*M
try{ A(0lM`X
if(ps!=null) { {y;n:^
ps.clearParameters(); 4`R(?
ps.close(); ]cruF#`%
ps=null; %%wNZ{
} M@ZI\
}catch(SQLException e){} 9g?(BI^z
DBUtils.closeConnection(conn); s9d_GhT%-
} ]9,;K;1<
} FGQzoS
public long getLast(){ v9UD%@tZ
return lastExecuteTime; :j`sr
} ~v"L!=~G;a
public void run(){ 1i] ^{;]
long now = System.currentTimeMillis(); ZAf7Tz\U
if ((now - lastExecuteTime) > executeSep) { Tb-F]lg$
//System.out.print("lastExecuteTime:"+lastExecuteTime); -`t^7pr
//System.out.print(" now:"+now+"\n"); wvPk:1wD5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); i 3SHg\~Z
lastExecuteTime=now; ;S*}WqP,
executeUpdate(); m#F`] {
} 9)=ctoZ'
else{ ei{eTp4HpV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RX5dO%
} 8KNZ](Dj
} cs'{5!i]
} 4'Zp-k?5`
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 d`6 'Z
n-OL0$Xu
类写好了,下面是在JSP中如下调用。 as_PoCoss
D#)b+7N-
<% ;({W#Wa
CountBean cb=new CountBean(); tRfo$4#NY
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @ry_nKr9
CountCache.add(cb); ]g&TKm
out.print(CountCache.list.size()+"<br>"); y^%y<~f
CountControl c=new CountControl(); IaXeRq?<
c.run(); fd2T=fz-
out.print(CountCache.list.size()+"<br>"); tnG# IU
*
%>