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: aoLYw 9
xQ4'$rL1d
CountBean.java 9?VyF'r=
^E)Kse.>
/* y7K&@Y
* CountData.java uXs.7+f
* `MMh"# xN
* Created on 2007年1月1日, 下午4:44 '6^20rj
* 6} DGEHc1
* To change this template, choose Tools | Options and locate the template under iKy_DV;J
* the Source Creation and Management node. Right-click the template and choose #6XN_<
* Open. You can then make changes to the template in the Source Editor. 6$1dd#
*/ ZRDY`eK
?o@5PL
package com.tot.count; 0]x g E
hXsd12
/** BPp`r_m8w}
* /Iwnl
* @author d$>TC(E=t
*/ OYw~I.Rq
public class CountBean { k7rFbrLZ
private String countType; )7U^&I,
int countId; Hzr<i4Y=w9
/** Creates a new instance of CountData */ R{s&6
public CountBean() {} SZO$#
public void setCountType(String countTypes){ 8p4J7 -
this.countType=countTypes; TU6e,G|t
} %9,:
public void setCountId(int countIds){ ' `0kW_'
this.countId=countIds; R,mOV8y"W[
} #cB=](N
public String getCountType(){ d|GQZAEJEt
return countType; uSZCJ#'G
} bRSE"B
public int getCountId(){ !PQ%h/ix
return countId; ^
olaq(z
} :%[=v(G[
} AJk0jh\.j%
0GUm~zi1
CountCache.java U(lcQC`$
%4F
Q~
/* ;7id![KI4
* CountCache.java [E9V#J89
* ,EkzBVgo
* Created on 2007年1月1日, 下午5:01 ^/nj2"
* .hBq1p
* To change this template, choose Tools | Options and locate the template under UKYQ @m
* the Source Creation and Management node. Right-click the template and choose W62 $ HI
* Open. You can then make changes to the template in the Source Editor. XJx$HM&0M
*/ XRZj+muTZ
=fJDFg
package com.tot.count; )gOVnA/M
import java.util.*; j_`
[Z
/** OT1
* "4Joou"U
* @author #[|~m;K(w
*/ 3Go/5X/
public class CountCache { 7_OC&hhL
public static LinkedList list=new LinkedList(); `pMI@"m
/** Creates a new instance of CountCache */ r[doN{%
public CountCache() {} ?q^o|Y/
public static void add(CountBean cb){ bjn: e!}
if(cb!=null){ 8Zj=:;
list.add(cb); $Hw
w
} 5yOIwzr&Uu
} lk.]!K$}
} r]h>Bb
[HRry2#s
CountControl.java VI xGD#m
r 6.`9
/* JD`IPQb~E
* CountThread.java xq6
eu
9
* 0bG[pp$[
* Created on 2007年1月1日, 下午4:57 (p19"p
* / @v V^!#1
* To change this template, choose Tools | Options and locate the template under UL{+mp
* the Source Creation and Management node. Right-click the template and choose 4*AkUkP:T
* Open. You can then make changes to the template in the Source Editor. ,/fB~On-
*/ +9^V9]{Vo
/9SEW!E
package com.tot.count; /M,C%.-
import tot.db.DBUtils; <{ER#}b:O
import java.sql.*; q8m{zSr
/** v3p0
* r\PO?1
* @author |wxAdPe
*/ ojc m%yd
public class CountControl{ w3n6md
private static long lastExecuteTime=0;//上次更新时间 v}cTS@0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X-,mNvz
/** Creates a new instance of CountThread */ ;\'d9C
public CountControl() {} {6I)6}w!k
public synchronized void executeUpdate(){ <)qJI'u|
Connection conn=null; HXeX!
PreparedStatement ps=null; ]| xfKDu
try{ q`Rc \aWB%
conn = DBUtils.getConnection(); ;s$,}O.
conn.setAutoCommit(false); gzMp&J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MJ\^i4
for(int i=0;i<CountCache.list.size();i++){ .OM^@V~T
CountBean cb=(CountBean)CountCache.list.getFirst(); r!N> FE
CountCache.list.removeFirst();
K^ 5f
ps.setInt(1, cb.getCountId()); Al
MMN"j
ps.executeUpdate();⑴ .A Dik}o
//ps.addBatch();⑵ gLss2i.r
} ?wi^R:2|j
//int [] counts = ps.executeBatch();⑶ Leu93f2
conn.commit(); ^KF%Z2:$
}catch(Exception e){ 20,}T)}Tm
e.printStackTrace(); _'mK=`>u
} finally{ TWeup6k
try{ 9Ro7xSeD
if(ps!=null) { u2E}DhV
ps.clearParameters(); #rI4\K
ps.close(); 'QdDXw5o
ps=null; Z#t}yC%^d
} [*K.9}+G_
}catch(SQLException e){} ~]Weyb[N
DBUtils.closeConnection(conn); "Ng%"Nz
} 4n0Iw I
} gQYs,
public long getLast(){ ;S?ei>Q
return lastExecuteTime; gSk0#Jt
} K2qKkV@
public void run(){ O~OM.:al&
long now = System.currentTimeMillis(); WkMB
if ((now - lastExecuteTime) > executeSep) { l+#uQo6cqQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); >sGiDK @
//System.out.print(" now:"+now+"\n"); B'-n
^';
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !!<H*9]+W;
lastExecuteTime=now; zXW)v/
ZD
executeUpdate(); _Wtwh0[r*
} 1wy?<B.f
else{ }vEMG-sxX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f;%=S:3
} BC)1FxsGf
} $}JWJ\-]
} `PtfPt<{
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ROJ=ZYof
a] P0PH~
类写好了,下面是在JSP中如下调用。 K*P:FCz
Aj*|r
<% Oh3A?!y#
CountBean cb=new CountBean(); ]Jnrs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); KjK-#F,@
CountCache.add(cb); 48)D%867.;
out.print(CountCache.list.size()+"<br>"); 629ogJo8
CountControl c=new CountControl(); ig ^x%!;
c.run(); wln"g,ct
out.print(CountCache.list.size()+"<br>"); eWr2UXv$
%>