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: S[F06.(1
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CountBean.java <IZt]P
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/* Ljd`)+`D
* CountData.java |/gt;H~:
* eB5>uKa
* Created on 2007年1月1日, 下午4:44 mU #F>
* +X/a+y-
* To change this template, choose Tools | Options and locate the template under 5*%Gh&)
* the Source Creation and Management node. Right-click the template and choose m8fj\,X
* Open. You can then make changes to the template in the Source Editor. g,+e3f
*/ P4[kW}R
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package com.tot.count; oN1D&*
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/** XR+
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* 0VNLhM(LM
* @author >s^$-
*/ [7@g*!+d
public class CountBean { G}pFy0W\S
private String countType; {U=J>#@G
int countId; Wzl/ @CPM
/** Creates a new instance of CountData */ QXkA%'@'
public CountBean() {} j*DPW)RkKX
public void setCountType(String countTypes){ LlX)xJ
this.countType=countTypes; ^+m`mc sE
} ]UvB+M]Lv)
public void setCountId(int countIds){ !J7`frv"(
this.countId=countIds; z(\aJW
} aoN\n]g
public String getCountType(){ fUjo',<s
return countType; fB$a)~
} E`fG9:6l]
public int getCountId(){ )7
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return countId; =?OU^u`C
} OXQ*Xpc
} :TQp,CEa
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CountCache.java Pm/<^z%
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/* M|DMoi8x
* CountCache.java u} mj)Nk
* ZE=sw}=
* Created on 2007年1月1日, 下午5:01 +KTfGwKt
* (]#^q8)]\9
* To change this template, choose Tools | Options and locate the template under /I 7V\
* the Source Creation and Management node. Right-click the template and choose Ugri _
* Open. You can then make changes to the template in the Source Editor. /z-rBfdy^
*/ S8#0Vo$)a
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package com.tot.count; W[&nQW$E
import java.util.*; <&E}db
/** =2p?_.|'
* Ypyi(_G(?>
* @author oYu xkG
*/ O=o}uB-*6
public class CountCache { (K[{X0T
public static LinkedList list=new LinkedList(); 9<Pg2#*N0
/** Creates a new instance of CountCache */ l?m"o-Gp3
public CountCache() {} =!\Nh,\eQ
public static void add(CountBean cb){ xTAfVN
if(cb!=null){ %%NoXW
list.add(cb); eQ>Ur2H8n
}
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} _5p$#U`
} g6Vkns4
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CountControl.java S\:^#Yi`
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/* &ivU4rEG
* CountThread.java Ux_tzd0!
* |Rfj
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* Created on 2007年1月1日, 下午4:57 G+c&e:ip<
* xv]z>4@z,
* To change this template, choose Tools | Options and locate the template under [7@blU
* the Source Creation and Management node. Right-click the template and choose /]U$OP*0
* Open. You can then make changes to the template in the Source Editor. ,l>w9?0Z
*/ if'=W6W
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package com.tot.count; /!Rva"
import tot.db.DBUtils; x@
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import java.sql.*; >fC&bab
/** lD0p=`.
* oywiX@]~7
* @author [piK"N
*/ !4p{b f
public class CountControl{ Kki(A4;7F
private static long lastExecuteTime=0;//上次更新时间 d4b!
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7\UHADr
/** Creates a new instance of CountThread */ l+Wux$6U
public CountControl() {} $J6
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public synchronized void executeUpdate(){ pz^S3fy
Connection conn=null; /4r2B.91O
PreparedStatement ps=null; {vD$od i
try{ }_lG2#Ll5
conn = DBUtils.getConnection(); q2%cLbI
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conn.setAutoCommit(false); j3sz"(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (pELd(*Ga
for(int i=0;i<CountCache.list.size();i++){ ,buX|
CountBean cb=(CountBean)CountCache.list.getFirst(); IUOf/mM5
CountCache.list.removeFirst(); ;u2[Ww~k
ps.setInt(1, cb.getCountId()); Mq91HmC(@
ps.executeUpdate();⑴ gN/!w:
//ps.addBatch();⑵ b~^'P
} /O[6PG
//int [] counts = ps.executeBatch();⑶ 2c Xae
conn.commit(); ^(;x-d3
}catch(Exception e){ oCCtjr
e.printStackTrace(); ROkwjw
} finally{ 8#QT[H
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try{ .<t {saToU
if(ps!=null) { ?i<l7
ps.clearParameters(); hrniZ^
ps.close(); ]>~.U~
ps=null;
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} ?^|[Yzk
}catch(SQLException e){} gV]4R"/
DBUtils.closeConnection(conn); IgbuMEfL
} 8>x5|
} [],[LkS
public long getLast(){ 'ON/WKJr|W
return lastExecuteTime; le5@WG/x
} ;W{z"L;nX
public void run(){ 5j`sJvq
long now = System.currentTimeMillis(); -)-:rRx-
if ((now - lastExecuteTime) > executeSep) { T.#_v#oM
//System.out.print("lastExecuteTime:"+lastExecuteTime); xI<l1@
//System.out.print(" now:"+now+"\n"); 'wPX.h?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^$oa`B^2JM
lastExecuteTime=now; V_
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executeUpdate(); 1XN%&VR>^D
} O+-+=W
else{ fS}Eu4Xe
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pqg2#@F.
} =)bOteWM
} Ls2OnL9
} @6ckB (
//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 OG#^d5(
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类写好了,下面是在JSP中如下调用。 C 9%bD
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<% Ow-ejo
CountBean cb=new CountBean(); lz=DGm
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); pKLcg"{[F
CountCache.add(cb); Ps0Cc _
out.print(CountCache.list.size()+"<br>"); `pbCPa{Y
CountControl c=new CountControl(); D0#U*tq;
c.run();
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out.print(CountCache.list.size()+"<br>"); $U,]c
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