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: _p?s9&
`c+/q2M
CountBean.java +u'I0>)S
",>H(wJ8
/*
Yav2q3
* CountData.java dO7;}>F$n
* ?r_l8
* Created on 2007年1月1日, 下午4:44 bw&myzs
* ?GBkqQ
* To change this template, choose Tools | Options and locate the template under Z2"?&pKV
* the Source Creation and Management node. Right-click the template and choose hO[3 Z^X
* Open. You can then make changes to the template in the Source Editor. US{3pkr;I]
*/ +%\oO/4Fs
8j1ekv
package com.tot.count; KLC{7"6e)
}`yiT<z
/** f f 7(
* [Vdz^_@Y
* @author D5?phyC[Z
*/ [@fz1{*
public class CountBean { (qwdQMj`
private String countType; 7~M<cD
int countId;
8[ry|J
/** Creates a new instance of CountData */ TCvSc\Q[:1
public CountBean() {}
fE,9zUo
public void setCountType(String countTypes){ *5,c Rz
this.countType=countTypes; 8dK0o>|}
} %i)B*9k
public void setCountId(int countIds){ 4e9q`~sO
this.countId=countIds; YwH./)r=
} <Q<+4Y{R
public String getCountType(){ 3z;_KmM
return countType; ;7Oi! BC
} G%#05jH
public int getCountId(){ SK$Vk[c]
return countId; }jSj+*
} x?D/.vrOY
} [&Hkn5yq
f c6g
CountCache.java >u J/TQU
+ E"[
/* ezTZnutZ
* CountCache.java G[idN3+#
* 7 gB{In0
* Created on 2007年1月1日, 下午5:01 Kud'pZ{P
* ZkB3[$4C=5
* To change this template, choose Tools | Options and locate the template under /,|CrNwY*
* the Source Creation and Management node. Right-click the template and choose (sw-~U%
* Open. You can then make changes to the template in the Source Editor. pJ,@Y>
*/ Y|0ow_oH
> 8]j
package com.tot.count; (foBp
import java.util.*; j?n+>/sG,
/** P"7ow-
* 2Ohp]G
* @author kpob b
*/ \)m"3yY
public class CountCache { GIHpSy`z
public static LinkedList list=new LinkedList(); 'PdmI<eXQ
/** Creates a new instance of CountCache */ '~-IV0v9
public CountCache() {} h[XGC=%
public static void add(CountBean cb){ 6xgv:,
if(cb!=null){ BQ05`nkF
list.add(cb); rVAL|0;3
} nv5u%B^
} -+U/Lrt>8
} G@d`F
.gZZCf&?
CountControl.java N
b3$4(F
{,O`rW_eS
/* aw}+'(?8]
* CountThread.java \Rk$t7ZH
* p*;Qz
* Created on 2007年1月1日, 下午4:57 "EftN5?/
* qg,Nb
* To change this template, choose Tools | Options and locate the template under zXc}W*ymj
* the Source Creation and Management node. Right-click the template and choose [EHrIn
* Open. You can then make changes to the template in the Source Editor. Ri?\m!o
*/ {w`:KR6o7
w.kCBDL
package com.tot.count; ]" x\=A
import tot.db.DBUtils; 9]_GNk-D
import java.sql.*; |#5 e|z5(
/** :7;[`bm(G
* +AQDD4bu
* @author zJ& b|L
*/ >mIg@knE
public class CountControl{ DacJ,in_I{
private static long lastExecuteTime=0;//上次更新时间 W$\X ~Q'0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 jv}=&d
/** Creates a new instance of CountThread */ w;`m- 9<Y
public CountControl() {} Ex($
public synchronized void executeUpdate(){ ?9U:g(v
Connection conn=null; )}X5u%woV
PreparedStatement ps=null; oP$kRfXS!<
try{ StQ@g
conn = DBUtils.getConnection(); lg/sMF>z\f
conn.setAutoCommit(false); ^Qh-(u`
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8@7AE"
for(int i=0;i<CountCache.list.size();i++){
EZ% .M*?
CountBean cb=(CountBean)CountCache.list.getFirst(); x%XT2+
CountCache.list.removeFirst(); A_r<QYq0|
ps.setInt(1, cb.getCountId()); DNth4z
ps.executeUpdate();⑴ _Dq Qfc%
//ps.addBatch();⑵ Xm[Czd]%
} <NQyP{p
//int [] counts = ps.executeBatch();⑶ 5t'Fv<g
conn.commit(); X!0kK8v
}catch(Exception e){ +J40wFI:y
e.printStackTrace(); e(\Q)re5Q
} finally{ .98.G4J>
try{ wA0eG@xi)
if(ps!=null) { DPPS?~Pq
ps.clearParameters(); t.z$j
ps.close(); G)+Ff5e0L[
ps=null; ze"~Ird
} rdI]\UH
}catch(SQLException e){} |9]PtgQv7
DBUtils.closeConnection(conn); LkaG[^tfN
} g3a/;wl
} y"R("j $
public long getLast(){ y*KC*/'"
return lastExecuteTime; T 'i~_R6
} 6e:P.HqjA
public void run(){ &l!$Sw-u;
long now = System.currentTimeMillis(); k.>6nho`TV
if ((now - lastExecuteTime) > executeSep) { ^n71'MW
//System.out.print("lastExecuteTime:"+lastExecuteTime); &
>b+loF
//System.out.print(" now:"+now+"\n"); 4.k`[q8
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r9;`
lastExecuteTime=now; DrFu r(=T
executeUpdate(); u[mY!(>nQ
} V#H8d_V
else{ 4f
jC
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =jG?v'X
} 9i[4"&K
} O99mic
} n>T:2PQ3
//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 cI3KB-lM#
e7's)C>/'
类写好了,下面是在JSP中如下调用。 .S6ji~;r
wEK%T P4
<% () <`t}FQ
CountBean cb=new CountBean(); pDmK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); kyK'
CountCache.add(cb); 59K}
out.print(CountCache.list.size()+"<br>"); Rj&qh`
CountControl c=new CountControl(); %2zas(b9j
c.run(); *k!(ti[
out.print(CountCache.list.size()+"<br>"); +0U#.|?
%>