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: WW3! ,ln_
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CountBean.java Aw,#oG {N
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/* 15Vo_
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* CountData.java 9oA-Swc[
* rrc>O*>{i
* Created on 2007年1月1日, 下午4:44 :}+m[g
* Vd+5an?
* To change this template, choose Tools | Options and locate the template under VCCG_K9'
* the Source Creation and Management node. Right-click the template and choose )A*Sl2ew
* Open. You can then make changes to the template in the Source Editor. N,?D<NjXl
*/ 1g1gu=|Q
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package com.tot.count; =G-u "QJ6
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/** #M=d)}[
* }<
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* @author Dwi[aC+k
*/ n$YCIW)0
public class CountBean { x|IG'R1:Y
private String countType; <B=!ZC=n
int countId; 8-
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/** Creates a new instance of CountData */ J"O#w BM9
public CountBean() {} i4*!t.eI
public void setCountType(String countTypes){ D[iIj_CKQ
this.countType=countTypes; h|
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} WX9pJ9d
public void setCountId(int countIds){ +6v;(] y
this.countId=countIds; ky5 gU[
} OJ\rT.{
public String getCountType(){ ~*Ir\wE
return countType; Y2Y!^A89
} t?j2Rw3f`I
public int getCountId(){ ;q&\>u:
return countId; 3kBpH7h4
} /@\3#2;
} hT<:)MG)+K
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CountCache.java ,Uv8[ci%9
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/* k^PqB+P!
* CountCache.java =7Y gES
* o )
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* Created on 2007年1月1日, 下午5:01 ^2PQ75V@.
* t(:6S$6{e
* To change this template, choose Tools | Options and locate the template under ;ckv$S[p
* the Source Creation and Management node. Right-click the template and choose SEXLi8;/
* Open. You can then make changes to the template in the Source Editor. 7#R&
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*/ $PQlaivA
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package com.tot.count; (u
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import java.util.*; 9h6xl i
/** aUy=D:\
* PHa#;6!5
* @author s
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*/ wzMWuA4vX
public class CountCache { Fq5);sX=
public static LinkedList list=new LinkedList(); 32IN;X|
/** Creates a new instance of CountCache */ e-os0F
public CountCache() {} s geP`O%
public static void add(CountBean cb){ EtH)E)
if(cb!=null){ {fMrx1
list.add(cb); `q exEk@S
} '+X9MzU*\
} t@/r1u|iq
} 3RRZVc*
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CountControl.java <!zItFMD[m
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/* qgca4VV|z
* CountThread.java @ec QVk
* _ }!Q4K
* Created on 2007年1月1日, 下午4:57 't{=n[
* "MXd!
* To change this template, choose Tools | Options and locate the template under 3a{QkVeV7
* the Source Creation and Management node. Right-click the template and choose (cYc03"
* Open. You can then make changes to the template in the Source Editor. #IBBaxOk
*/ Ok6Y'P
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package com.tot.count; =QyO$:t
import tot.db.DBUtils; eS@RA2
import java.sql.*; TL7-uH
/** FZA8@J|Q4
* ^[%~cG
* @author i}<R>]S
*/ ]V@!kg(p8
public class CountControl{ MO#%w
private static long lastExecuteTime=0;//上次更新时间 4g1u9Sc0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~*B1}#;
/** Creates a new instance of CountThread */ EmY4>lr
public CountControl() {} T"d]QYJS
public synchronized void executeUpdate(){ {b<8Z*4W
Connection conn=null; Lp
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PreparedStatement ps=null; 9$DVG/
try{ g'Xl>q
conn = DBUtils.getConnection(); g>im2AD+e
conn.setAutoCommit(false); 6xFZv
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LOida# R
for(int i=0;i<CountCache.list.size();i++){ DR0W)K
^
CountBean cb=(CountBean)CountCache.list.getFirst(); ZTmdS
CountCache.list.removeFirst(); %okEN!=
ps.setInt(1, cb.getCountId()); N'`*#UI+
ps.executeUpdate();⑴ @ ~sp:l
//ps.addBatch();⑵ i2j)%Gc}
} 9i`LOl:;
//int [] counts = ps.executeBatch();⑶ _u:#2K$
conn.commit(); _ _)Z Q
}catch(Exception e){ r\3In-(AT
e.printStackTrace(); H7SqM D*y9
} finally{ Xj-3C[8@
try{ kcYR:;y
if(ps!=null) { S,8zh/1y
ps.clearParameters(); T]vD ,I+
ps.close(); *Cb(4h-
ps=null; @P.l8|w
} #SqOJX~Q
}catch(SQLException e){} 0"QE,pLe4
DBUtils.closeConnection(conn); U50X`J
} 3?geJlD4
} TRq~n7Y7C
public long getLast(){ A!f0AEA,
return lastExecuteTime; Yr31GJ}K
} X!
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public void run(){ _N]yI0k(
long now = System.currentTimeMillis(); |(V%(_s
if ((now - lastExecuteTime) > executeSep) { e!-'O0-Kw
//System.out.print("lastExecuteTime:"+lastExecuteTime); JIQzP?+?
//System.out.print(" now:"+now+"\n"); GS,pl9#V_
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zyR pHM$E
lastExecuteTime=now; f@}( <#
executeUpdate(); wd]Yjr#%Ii
} qQ_B[?+W
else{ Qpc{7#bp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); *=Fcu@
} +|?c_vD
} bCrB'&^t
} `Q8 D[
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 #X8[g _d/
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类写好了,下面是在JSP中如下调用。 q38; w~H
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<% Kaa*;T![
CountBean cb=new CountBean(); Gs6#aL}]R
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <#Lw.;(U;k
CountCache.add(cb); |<V{$),k
out.print(CountCache.list.size()+"<br>"); b?$09,{0
CountControl c=new CountControl(); (NQ[AypMI
c.run(); q-Qws0\v.
out.print(CountCache.list.size()+"<br>"); +{I\r|
%>