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: bVSa}&*kM
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CountBean.java +Tc<|-qQn
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/* e5maZ(.;F
* CountData.java n
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* &N GYV
* Created on 2007年1月1日, 下午4:44 RN238]K
* &^FCp'J-
* To change this template, choose Tools | Options and locate the template under {EGiGwpf
* the Source Creation and Management node. Right-click the template and choose % ribxgmd
* Open. You can then make changes to the template in the Source Editor. , fFB.q"
*/ hc2[,Hju{O
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package com.tot.count; GJai!$v
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/** Q]Q i
* Y v }G"-=
* @author Brr{iBz*"
*/ &F9BaJ
public class CountBean { u*Z>&]W_
private String countType; zM"OateA
int countId; VI0^Zq!6R
/** Creates a new instance of CountData */ +'Pl?QyH
public CountBean() {} 'A
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public void setCountType(String countTypes){ VlRN
this.countType=countTypes; YlwCl4hq
} |`_qmk[:R
public void setCountId(int countIds){ ?Q[uIQ?dV
this.countId=countIds; //]g78]=O
} lHv;C*(_=
public String getCountType(){ 8hba3L_Z
return countType; xOP%SF
} |8PUmax
public int getCountId(){ `Gzukh
return countId; wO&`3Q3~$
} ^_#0\f
} \k / N/&;
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CountCache.java P66{l^
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/* Re-~C[zwT
* CountCache.java SkBa- *MC
* I=6\z^:
* Created on 2007年1月1日, 下午5:01 $cEl6(66iX
* vpcx 1t<
* To change this template, choose Tools | Options and locate the template under rM#jxAb
* the Source Creation and Management node. Right-click the template and choose K@Q_q/(%;
* Open. You can then make changes to the template in the Source Editor.
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*/ ]c]rIOTN
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package com.tot.count; /~NsHStn
import java.util.*; i`)bn1Xm
/** eU'DQp*
* `G&W%CHB
* @author Er^ijh,
*/ b|U&{I>TH
public class CountCache { zJWBovT/
public static LinkedList list=new LinkedList(); 0'*whhH
/** Creates a new instance of CountCache */ ]4-lrI1#
public CountCache() {} ce th )Xm
public static void add(CountBean cb){ BM!\U 6
if(cb!=null){ G[n^SEY!
list.add(cb); a_XM2dc%
} "-GjwB
} S%<RV6{aiM
} \.y|=Ql_u
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CountControl.java {%5k1,/(
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/* *#-X0}'s
* CountThread.java RX8$&z
* 4V9DPBh
* Created on 2007年1月1日, 下午4:57 m6tbN/EJZ
* j9Ptd$Uj
* To change this template, choose Tools | Options and locate the template under @-nCK Yj
* the Source Creation and Management node. Right-click the template and choose sE@t$'=
* Open. You can then make changes to the template in the Source Editor. &cztUM(
*/ x*&
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package com.tot.count; 0KO_bF#EB=
import tot.db.DBUtils; *c4uCI:0t
import java.sql.*; lMz5))Rr
/** La9v97H:
* sc'QNhrW
* @author *t J+!1
*/ __r]@hY
public class CountControl{ a)=WDRk
private static long lastExecuteTime=0;//上次更新时间 T`KH7y|bv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YYU Di@K
/** Creates a new instance of CountThread */ <jE6ye(R
public CountControl() {} Ab`mID:
public synchronized void executeUpdate(){ yPrp:%PS
Connection conn=null; UOHU1.3$T
PreparedStatement ps=null; rU<NHFGj4
try{ O4@sN=o
conn = DBUtils.getConnection(); hNs970i
conn.setAutoCommit(false); D,%R[F?5O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g\;AU2?p7
for(int i=0;i<CountCache.list.size();i++){ e\x=4i
CountBean cb=(CountBean)CountCache.list.getFirst(); <6^MVaD
CountCache.list.removeFirst(); {WUW.(^]G
ps.setInt(1, cb.getCountId()); y>wrm:b-O
ps.executeUpdate();⑴ >FED*C4
//ps.addBatch();⑵ ?#?[6t
} ks|[`FH
//int [] counts = ps.executeBatch();⑶ ktLXL;~X
conn.commit(); LW6&^S?4{
}catch(Exception e){ =S/$h}Vi
e.printStackTrace(); e@' rY#:u
} finally{ }YJ(|z""
try{ 3"=% [
if(ps!=null) { g.OBh_j-v
ps.clearParameters(); &EKP93
ps.close(); H?98^y7
ps=null; Qb}7lm{r
} dd1m~Gm
}catch(SQLException e){} U]j4Izq
DBUtils.closeConnection(conn); U;Z6o1G
} f"t\-ux.b
} {o"X8
public long getLast(){ RN\4y{@
return lastExecuteTime; 54~`8f
} 4]9+
public void run(){ ?hUC#{
long now = System.currentTimeMillis(); 4GWt.+{J$
if ((now - lastExecuteTime) > executeSep) { 'W>Bz,M6yo
//System.out.print("lastExecuteTime:"+lastExecuteTime); WmU4~.
//System.out.print(" now:"+now+"\n"); pFi.?|6"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); wP28IB:^
lastExecuteTime=now; Y: &?xR
executeUpdate(); [^xLK
} xc dy/J&
else{ #-
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RG/M-
} h-
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} 3qOq:ZkQ
} (7BG~T
//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 Poy ]5:.
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类写好了,下面是在JSP中如下调用。 0VC8'6S_k
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<% yoa"21E$
CountBean cb=new CountBean(); xLX<