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: T-LX>*
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CountBean.java 3=Q:{
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/* lrAhdi
* CountData.java #;yxn.</
* RR+{uSO,t
* Created on 2007年1月1日, 下午4:44 B[k=6EU8k
* <D[0mi0
* To change this template, choose Tools | Options and locate the template under uGv|!UQw
* the Source Creation and Management node. Right-click the template and choose {Q}F.0Q
* Open. You can then make changes to the template in the Source Editor. L>h|1ZK
*/ N;`/>R4|I
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package com.tot.count; `a%MD>R_Lg
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/** L#",.x
* :r(dMU3%
* @author <5?pa3
*/ o_1N "o%
public class CountBean { kO5lLqE
private String countType; cNbUr
int countId; a%A!DzS
/** Creates a new instance of CountData */ GsmXcBzDw2
public CountBean() {} OXm`n/64+
public void setCountType(String countTypes){ P)kJ[Zv>f
this.countType=countTypes; !
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} j^7A}fz
public void setCountId(int countIds){ ;=7K*npT
this.countId=countIds; a'-u(Bw
} V2!0),]B
public String getCountType(){ D#AqZS>B
return countType; Y
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} lLp,sNAj
public int getCountId(){ >.6|\{*sG
return countId; M.K^W `
} 9vz\R-un
} Q6W![571;
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CountCache.java {fnx=BaG
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/* Kv(R|d6Lp
* CountCache.java \nt~K}a
* zGFD71=#
* Created on 2007年1月1日, 下午5:01 ~_-]>
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* Bb:C^CHIQm
* To change this template, choose Tools | Options and locate the template under p]%di8&;N
* the Source Creation and Management node. Right-click the template and choose K8aqC{
* Open. You can then make changes to the template in the Source Editor. ni&|;"Nt-
*/ IH;sVT$M
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package com.tot.count; JwB'B
import java.util.*; :{#O
/** &s='$a;4
* GPGE7X'
* @author 0muC4
*/ B
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public class CountCache { {Q3OT
public static LinkedList list=new LinkedList(); +?Ii=* 7n
/** Creates a new instance of CountCache */ eD?&D_l~6
public CountCache() {} ly-(F2
public static void add(CountBean cb){ W;'fAohr
if(cb!=null){ E?G'F3i
list.add(cb); J7* o%W*V
} \c
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} Wk<fNHg
} u0h%4f!X
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CountControl.java RbX9PF"|+
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/* I@MG?ZQ
* CountThread.java uhh7Ft#H
* Y>8Qj+d
* Created on 2007年1月1日, 下午4:57 N#K)Z5J)b
* cry1gnWG
* To change this template, choose Tools | Options and locate the template under &h0LWPl
* the Source Creation and Management node. Right-click the template and choose -;7xUNQ
* Open. You can then make changes to the template in the Source Editor. Tb$))O}
*/ 3)y1q>CQf
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package com.tot.count; E ?Mgbd3
import tot.db.DBUtils; I&{T 4.B:U
import java.sql.*; s`jlE|jtN
/** n.&7lg^X
* SO=gG 2E
* @author
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*/ Cgx:6TRS
public class CountControl{ b^VRpv
private static long lastExecuteTime=0;//上次更新时间 oFj_o
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #NW+t|E
/** Creates a new instance of CountThread */ (dq_,LI
public CountControl() {} =/Gd<qz3
public synchronized void executeUpdate(){ . vb##D
Connection conn=null; -N*[f9EJB
PreparedStatement ps=null; $6a9<&LP_
try{ Gr\ ]6
conn = DBUtils.getConnection(); A?H#bRAs
conn.setAutoCommit(false); Hu"$)V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 509T?\r
for(int i=0;i<CountCache.list.size();i++){ ]SCHni_
CountBean cb=(CountBean)CountCache.list.getFirst(); ^eh.Iml'@
CountCache.list.removeFirst(); 7GOBb|
ps.setInt(1, cb.getCountId()); -G.N
ps.executeUpdate();⑴ ]p`y
//ps.addBatch();⑵ l8FJ \5'M
} 5vyg-'
//int [] counts = ps.executeBatch();⑶ A|\A|8=b
conn.commit(); ,`}yJ*7
}catch(Exception e){ pUHgjwT'U
e.printStackTrace(); ! :&SfPv
} finally{ ,VS\ mG/}s
try{ %JM$]
if(ps!=null) { zMv`<m%
ps.clearParameters(); J\y^T3Z
ps.close(); H~Uf2A)C
ps=null; Sb[>R(0:
} Ddr.6`VJ
}catch(SQLException e){} q[\ 3,Y
DBUtils.closeConnection(conn); |dgiW"tUm
} NftnbsTmy
} [P
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public long getLast(){ _d]{[&
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return lastExecuteTime; Zi~.
} yMN JHiE/
public void run(){ juR>4SH
long now = System.currentTimeMillis(); 3gUY13C}:p
if ((now - lastExecuteTime) > executeSep) { .b,\.0N
//System.out.print("lastExecuteTime:"+lastExecuteTime); |8'}mjs.Q
//System.out.print(" now:"+now+"\n"); 9WG=3!-@
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,/?J!W@m
lastExecuteTime=now; oJTEN}fL
executeUpdate(); Ak?9a_f
} M2Nh3ijr
else{ f SkC>mWv
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); h"1}j'2>@
} Fqeqn[,
} }k VC]+
} }dN\bb{#
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 tx5bmF;b)
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类写好了,下面是在JSP中如下调用。 Yh1</C
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<% PA^*|^;Xh
CountBean cb=new CountBean(); oDZZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5;XC!Gz
CountCache.add(cb); E!Q@AZ
out.print(CountCache.list.size()+"<br>"); BbX$R`f
CountControl c=new CountControl(); -9om,U`t
c.run(); Tv|'6P
out.print(CountCache.list.size()+"<br>"); }ekNZNcuM
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