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: [%LIW%t|
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CountBean.java h[(.
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/* BG/Q7s-?K
* CountData.java SPu+t3
* eHE?#r16Z
* Created on 2007年1月1日, 下午4:44 XP%/*am
* (/$a*$
* To change this template, choose Tools | Options and locate the template under Bcl6n@{2f
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. \p.eY)>
*/ {ovW6#
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package com.tot.count; .dPy<6E
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/** @V =HY
* uz;zmK
* @author }'u0Q6Obj
*/ wNm 1H[{
public class CountBean { b=PB" -
private String countType; AFdBf6/"i
int countId; +yd{-iH
/** Creates a new instance of CountData */ n?mV(? N
public CountBean() {} 9.>he+
public void setCountType(String countTypes){ 4Ai#$SHLm
this.countType=countTypes; >Q#\X=a>
} zvOSQxGQ
public void setCountId(int countIds){ IeT1Jwe
this.countId=countIds; ~O8Xj6
} b wqd`C
public String getCountType(){ sjj,q?
return countType;
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} #-7w|
public int getCountId(){ UPcx xtC
return countId; 8~|tl,
} >NJ`*M
} $s<bKju
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CountCache.java
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/* f#3!Q!C^
* CountCache.java ~y" ^t@!E
* }@TtX\7(D
* Created on 2007年1月1日, 下午5:01 >Pwu>
* A(1dq
* To change this template, choose Tools | Options and locate the template under <IwfiI3y
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. |5g1D^b]s^
*/ x.%x|6G*
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package com.tot.count; w$$vR
import java.util.*; /SKgN{tWe
/** 3:MAdh[w
* -p*j9
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* @author _ lE
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*/ VRA0p[
public class CountCache { ~#PC(g
public static LinkedList list=new LinkedList(); R4AKp1Y
/** Creates a new instance of CountCache */ Sp\
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public CountCache() {} JW9U&Bj{
public static void add(CountBean cb){ h
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if(cb!=null){ \(;X3h
list.add(cb); 8/T,.<5
} C@OY)!x!
} VWT\wAL
} HwxME%w
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CountControl.java `kM:5f+>W
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/* hM[QR'\QS
* CountThread.java &pN/+,0E
* {wCzm
* Created on 2007年1月1日, 下午4:57 A5kz(pj
* 'D[g{LkL
* To change this template, choose Tools | Options and locate the template under !A=>B=.|D
* the Source Creation and Management node. Right-click the template and choose Q|Go7MQZ@k
* Open. You can then make changes to the template in the Source Editor. <~iA{sY)O
*/ =x-@-\m
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package com.tot.count; vI0::ah/
import tot.db.DBUtils; Y~g*"J5j
import java.sql.*; >Ni<itze$i
/** g/BlTi
* _28vf Bl?
* @author C,G$C7$%
*/ -Ou@T#h"
public class CountControl{ zOT(>1'
private static long lastExecuteTime=0;//上次更新时间 u
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3-U@==:T
/** Creates a new instance of CountThread */ sHf.xc
public CountControl() {} e!p?~70
public synchronized void executeUpdate(){ HK4 *+
Connection conn=null; 0})mCVBY
PreparedStatement ps=null; X.FFBKjf[e
try{ Y4,LXuQ
conn = DBUtils.getConnection(); MtXTh*4
conn.setAutoCommit(false); t`eUD>\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b5Vn _;V*
for(int i=0;i<CountCache.list.size();i++){ ;6/dFOZn
CountBean cb=(CountBean)CountCache.list.getFirst(); D>m!R[!o
CountCache.list.removeFirst(); qcR"i+b
ps.setInt(1, cb.getCountId()); i5CBLv
ps.executeUpdate();⑴ 5/C#*%EH'
//ps.addBatch();⑵ oa:30@HSb
} 2P ic 4Z
//int [] counts = ps.executeBatch();⑶ jLCZ
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conn.commit(); :}3;z'2]l
}catch(Exception e){ @ !m+s~~]h
e.printStackTrace(); x$;kA}gy
} finally{ g4NbzU[I
try{ r0fEW9wL
if(ps!=null) { jyFXAs2
ps.clearParameters(); /qObXI
ps.close(); qJq2Z.>hy
ps=null;
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} qgk6 \&K[
}catch(SQLException e){} %eQw\o,a
DBUtils.closeConnection(conn); V>:ubl8j0l
} -Gn0TA2/C
} mrId`<L5l{
public long getLast(){ Y=tx
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return lastExecuteTime; U]W+ers
} 5,u'p8}.
public void run(){ Nlk'
long now = System.currentTimeMillis(); < (<IRCR
if ((now - lastExecuteTime) > executeSep) { %:vM D
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); mQqv{1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u!D AeE
lastExecuteTime=now; 6y}|IhX?z
executeUpdate(); 7<7
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} /.<2I
else{ ,/6 aA7(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); XXA1%Lw%
} 59Lmv
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} cgF?[Z+x
} oRQJ YH
//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 b@m\ca
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类写好了,下面是在JSP中如下调用。 t8\XOj
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<% NZ=`iA8)X
CountBean cb=new CountBean(); P/;d|M(
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0VBbSn}Z<
CountCache.add(cb); jce^Xf
out.print(CountCache.list.size()+"<br>"); ,+hH|$
CountControl c=new CountControl(); K3On8
c.run(); "*N=aHsj
out.print(CountCache.list.size()+"<br>"); Kt\#|-{CH-
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