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: dj7hx"BI
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CountBean.java 3|4|*6
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/* ^l=!JP=M=
* CountData.java Hmd]
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* %GA"GYL9'
* Created on 2007年1月1日, 下午4:44 e .2ib?8
* 9-
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* To change this template, choose Tools | Options and locate the template under 2s&*
* the Source Creation and Management node. Right-click the template and choose NOiN^::m
* Open. You can then make changes to the template in the Source Editor. uU <=d
*/ Q$1bWUS&
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package com.tot.count; Dhw(#{N
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/** 3U.88{y
* luuX2Mx>o
* @author q[`]D7W
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*/ ^~@U]
public class CountBean { Ov4y%Pj
private String countType; 5JCG2jqx0
int countId; 5eoska#y
/** Creates a new instance of CountData */ Hl/
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public CountBean() {} 6@e+C;j=
public void setCountType(String countTypes){ 0Lc9M-Lg
this.countType=countTypes; X4AyX.p
} [t7]{d*
public void setCountId(int countIds){ hMUs"
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this.countId=countIds; *:t|qgJI#+
} ~\.w^*$#Y
public String getCountType(){ Q6AC(n@:FV
return countType; %Nhx;{
} Mjfx~I27
public int getCountId(){ pUq1|)g
return countId; oA7;.:3
} Y/ee~^YxK'
} wsN?[=l{s
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CountCache.java 'fF;(?
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/* ?~;:jz|9<'
* CountCache.java 2?,EzBeal
* Ikiib
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* Created on 2007年1月1日, 下午5:01 7J|VD#DE$Y
* .J.-Mm`.
* To change this template, choose Tools | Options and locate the template under ;F#7Px(q
* the Source Creation and Management node. Right-click the template and choose 8J~1-;
* Open. You can then make changes to the template in the Source Editor. w{uuSe
*/ &A)B~"[~
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package com.tot.count; &S]@Ot<z
import java.util.*; ./D$dbu3
/** ~r$jza~o(
* +$(2:S*r
* @author <Ib[82PU
*/ 4RV%Z!kcD!
public class CountCache { l)w Hl%p
public static LinkedList list=new LinkedList(); P*@2.#oO
/** Creates a new instance of CountCache */ Q~Hh\L t
public CountCache() {} \nB8WSvk2W
public static void add(CountBean cb){ ]oV{t<0a
if(cb!=null){
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list.add(cb); UybW26C;aU
} ,4,V4 N
} +sx 8t
} -zO2|@S,
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CountControl.java a/U2xq{x
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/* !>`N$-U X
* CountThread.java <~X >[PK<
* 1>Dl\czn
* Created on 2007年1月1日, 下午4:57 UMp/\&0
* >Clh] ;K
* To change this template, choose Tools | Options and locate the template under 7,MS '2nz
* the Source Creation and Management node. Right-click the template and choose G,<T/f
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* Open. You can then make changes to the template in the Source Editor. qdG~!h7j
*/ CWG6;NT6m
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package com.tot.count; m6yIR6H
import tot.db.DBUtils; zYv#:>C8
import java.sql.*; F3lw@b3])
/** Z,;cCxE
* ai^4'{#zi
* @author [;.`,/
*/ Ty@=yA17
public class CountControl{ Q2];RS3.
private static long lastExecuteTime=0;//上次更新时间 dg7=X{=9jv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ow;R$5G
/** Creates a new instance of CountThread */ f8<o8*`7
public CountControl() {} 1b>C<\
public synchronized void executeUpdate(){ ;t>Z+O%
Connection conn=null; ]:$
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PreparedStatement ps=null; %=<IGce
try{ xf>z @)e
conn = DBUtils.getConnection(); HygY>s+3[
conn.setAutoCommit(false); tPyyZ#,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~;OYtz
for(int i=0;i<CountCache.list.size();i++){ RF!1oZ
CountBean cb=(CountBean)CountCache.list.getFirst(); F'?I-jtI
CountCache.list.removeFirst(); 6V+ qnUk
ps.setInt(1, cb.getCountId()); O^I[
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ps.executeUpdate();⑴ MZSxQ8
//ps.addBatch();⑵ Hj1
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} qy!Ou3^
//int [] counts = ps.executeBatch();⑶ y8bM<e2
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conn.commit(); '7B"(dA&C
}catch(Exception e){ p'?w2YN/
e.printStackTrace(); $O:w(U
} finally{ +|%Sx
try{ 1GE|Wd
if(ps!=null) { .`Zf}[5[
ps.clearParameters(); Ei@M$Fd
ps.close(); 3Gr&p6
ps=null; w,j cm;
} l t]B#, '
}catch(SQLException e){} y9;#1:ic
DBUtils.closeConnection(conn); 9f}XRz
} Y&r]lD
} %xyX8c{sP
public long getLast(){ SHqyvF
return lastExecuteTime; PI?j_8
} Lg`Jp&Kg
public void run(){ mf|pNiQ,
long now = System.currentTimeMillis(); fRg=!<#%
if ((now - lastExecuteTime) > executeSep) { a%J6f$A#
//System.out.print("lastExecuteTime:"+lastExecuteTime); z]$j7 dp
//System.out.print(" now:"+now+"\n"); +ydm,aKk
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); NyI;v=
lastExecuteTime=now; '3kcD7
executeUpdate(); R+$8w2#
} dNVv4{S
else{ VZA3IbK}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); t&814Uf&\
} >e8JK*Blz
} Gbd?%{Xc-
} ~%q7Vmk9
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 {=At#*=A
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类写好了,下面是在JSP中如下调用。 5FuK \y
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<% "L~@.W!@
CountBean cb=new CountBean(); \kwe51MQ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Xn7[n
CountCache.add(cb); }g,X5v?W
out.print(CountCache.list.size()+"<br>"); s%dF~DSK
CountControl c=new CountControl(); .wFU:y4r
c.run(); g+Ph6W
out.print(CountCache.list.size()+"<br>"); YbvX$/zGu
%>