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: VP>*J`'H
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CountBean.java `vMhrn
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/* 9@ YKx0
* CountData.java zBlv?JwG
* Cdib{y<ji
* Created on 2007年1月1日, 下午4:44 L-}J=n\
* 5wmd[YL
* To change this template, choose Tools | Options and locate the template under #GLW3}
* the Source Creation and Management node. Right-click the template and choose jQzl!f1c3
* Open. You can then make changes to the template in the Source Editor. Db<#gH
*/ @J&korU
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package com.tot.count; #gqh0 27
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/** JLnv O
* w8>h6x"
* @author g\fj6
*/ 4")`}T
public class CountBean { =$Mf:F@
private String countType;
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int countId; QOo'Iv+EL
/** Creates a new instance of CountData */ *Q^z4UY
public CountBean() {} )PTvw>
public void setCountType(String countTypes){ ZaU8eg7
this.countType=countTypes; k`Ifl)
} >9rZVNMU
public void setCountId(int countIds){ }a$.ngP
this.countId=countIds;
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} 7M~sol[*
public String getCountType(){ Nwz?*~1
return countType; /$CTz xd1
} ?/"|tuQMW
public int getCountId(){ l>}f{az-T
return countId; <BED&j!qvP
} ~<f[7dBv
} ^\AeX-q2v'
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CountCache.java K\rQb
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/* m<hP"j
* CountCache.java KF00=HE|]
* .a]#AFX
* Created on 2007年1月1日, 下午5:01 -1,0hmn=+
* +ZM,E8
* To change this template, choose Tools | Options and locate the template under I7oA7@zv
* the Source Creation and Management node. Right-click the template and choose ?}Z t&(#
* Open. You can then make changes to the template in the Source Editor. #M16qOEw
*/ X8Q'*
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package com.tot.count; WN+i 3hC
import java.util.*; !Fp %2gt|
/** u*G<?
* a&x:_vv
* @author )^ Y+Vn
*/ X n$ZA-
public class CountCache { R,G*]/r`
public static LinkedList list=new LinkedList(); :R,M Y"(
/** Creates a new instance of CountCache */ s:}? rSI
public CountCache() {} 'ZW(Hjrd
public static void add(CountBean cb){ }I&.xzJ
if(cb!=null){ u1$6:"2@5k
list.add(cb); ? +L,
} \4q|Qno8
} qK a}O*
} &\N>N7/1
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CountControl.java \~l_w
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/* @|SeabN^-
* CountThread.java (c(F1=K
* ZpVkgX4
* Created on 2007年1月1日, 下午4:57 ;"Kgg:K>W
* 5,1<A@H
* To change this template, choose Tools | Options and locate the template under 0cq@lT6
* the Source Creation and Management node. Right-click the template and choose -!Myw&*\V
* Open. You can then make changes to the template in the Source Editor. A/>Q5)
*/ (QiA5!wg
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package com.tot.count; d
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import tot.db.DBUtils; N
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import java.sql.*; W5
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/** "Gp[.=.z?
* RW L0@\
* @author ]=00<~ l*q
*/ [j+:2@
public class CountControl{ :3n@].
private static long lastExecuteTime=0;//上次更新时间 vd4@ jZ5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;>v.(0FE6
/** Creates a new instance of CountThread */ /h0bBP
public CountControl() {} k{SGbC1=VK
public synchronized void executeUpdate(){ ^-_*@e*JE
Connection conn=null; 1.cP3kl
PreparedStatement ps=null; sllT1%?
try{ "l56?@- x
conn = DBUtils.getConnection(); `N *:,8j
conn.setAutoCommit(false); A)&FcMO*z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s$R /!,c
for(int i=0;i<CountCache.list.size();i++){ [Cl0Kw.LD
CountBean cb=(CountBean)CountCache.list.getFirst(); JpC'(N
CountCache.list.removeFirst(); 7y'":1
ps.setInt(1, cb.getCountId()); >ou=}/<
ps.executeUpdate();⑴ ?{S>%P A_B
//ps.addBatch();⑵ .>B'oD
} 2!^=G=H/
//int [] counts = ps.executeBatch();⑶ ! I@w3`
conn.commit(); EL?(D
}catch(Exception e){ 'QCIKCn<
e.printStackTrace(); Tn}`VW~
} finally{ 6h;(b2p{
try{ )hZ7`"f,ZN
if(ps!=null) { t )zd'[
ps.clearParameters(); r)iEtT!p*
ps.close(); ~T1W-ig4[*
ps=null; +.V+@!
} 9(N
}catch(SQLException e){} %#x4wi
DBUtils.closeConnection(conn); Tc6cBe,
} 2I-d.{
} o&?c,FwN
public long getLast(){ h<G4tjtk
return lastExecuteTime; i.Rl&t
} .11l(M
public void run(){ &kg^g%%
long now = System.currentTimeMillis(); _!03;zrO
if ((now - lastExecuteTime) > executeSep) { kv:9Fm\$
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0^ODJ7
//System.out.print(" now:"+now+"\n"); fu"cX;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); kamQZzPe
lastExecuteTime=now; a: "1LnvR
executeUpdate(); SyvoN,;Q
} PM\Ju]
else{ l_^OdQ9D
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); =0)|psCsM
} mTE(JZt
} DK IH{:L7
} F0:]@0>r
//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 <7^|@L
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类写好了,下面是在JSP中如下调用。 $Ll9ak}
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<% NI V}hf YF
CountBean cb=new CountBean(); #fuUAbU0X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z#tIa
CountCache.add(cb); iq; |
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out.print(CountCache.list.size()+"<br>"); 75# 8P?i
CountControl c=new CountControl(); {D4FYr
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c.run(); 6@N,'a8r
out.print(CountCache.list.size()+"<br>"); 8Qg10Yjy
%>