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: ]mx1djNA
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CountBean.java K^c%$n:}+
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/* kp,$ NfD
* CountData.java b25C[C5C
* Wtp;se@#
* Created on 2007年1月1日, 下午4:44 W<Asr@
* +wm%`N;v<
* To change this template, choose Tools | Options and locate the template under `q7X(x
* the Source Creation and Management node. Right-click the template and choose }IV=qW,
* Open. You can then make changes to the template in the Source Editor. AL[,&_&uV
*/ -\8v{ry
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package com.tot.count; 77%I%<#
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/** :Gf
* KOhIk*AC'
* @author ?rQIUP{D7
*/ !Gh*Vtd8-
public class CountBean { f+4j ^y}
private String countType; +w(B9rH
int countId; 6f;20dn6
/** Creates a new instance of CountData */ P u,JR
public CountBean() {} byX)4&
public void setCountType(String countTypes){ )Vpt.4IBd
this.countType=countTypes; A_I\6&b4
} 70N Lv
public void setCountId(int countIds){ "IRF^1 p
this.countId=countIds; T0%l$#6v
} Mo[yRRS#
public String getCountType(){ +sx$%N
return countType; ]Tn""3#1g
} mh,a}bX{
public int getCountId(){ M)sAMfuUw
return countId; r!/<%\S
} "_n})s
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} <!derr-K
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CountCache.java Pr#uV3\
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/* !OMl-:KUzE
* CountCache.java /2:s g1
* 1( rN
* Created on 2007年1月1日, 下午5:01 $[+)N~
* G/yYIs
* To change this template, choose Tools | Options and locate the template under Z8\/Fb
* the Source Creation and Management node. Right-click the template and choose G)&S%R!i\N
* Open. You can then make changes to the template in the Source Editor. 2X 0<-Y#'
*/ @8lT*O2j
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package com.tot.count; F<Ig(Wl#az
import java.util.*; F_nXsKem
/** y*#+:D]o*
* mIv}%hD
* @author wfQImCZ>l
*/ P$&l1Mp
public class CountCache { mtVoA8(6
public static LinkedList list=new LinkedList(); .FA99|:
/** Creates a new instance of CountCache */ b-YmS=*
public CountCache() {} gm7 [m}
public static void add(CountBean cb){ $dF$-y<[0
if(cb!=null){ Z~ u3{
list.add(cb); fY!9i5@'
} nt*K@
} `a9iq>
} il$eO 7
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CountControl.java tiF-lq
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/*
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* CountThread.java DJ|lel/'
* =!IoL7x
* Created on 2007年1月1日, 下午4:57 S#S&_#$`,X
* mi@ni+2Tn
* To change this template, choose Tools | Options and locate the template under !JA//{?
* the Source Creation and Management node. Right-click the template and choose `pfRY!
* Open. You can then make changes to the template in the Source Editor. kQO-V4z!
*/ ^CP>|JWD^
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package com.tot.count; *Nur>11D
import tot.db.DBUtils; 'q1cc5(ueV
import java.sql.*; +nL#c{
/** j5rMY=|F
* {pC$jd>T
* @author O6Y1*XTmH6
*/ TEi1,yc
public class CountControl{ ?b\oM
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private static long lastExecuteTime=0;//上次更新时间 *s|'V+1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j eyGIY
/** Creates a new instance of CountThread */ 0N_u6*@
public CountControl() {} ku
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public synchronized void executeUpdate(){ =4gPoS
Connection conn=null; |2Uw8M7.E
PreparedStatement ps=null; 3e)$ <e
try{ {2U3
conn = DBUtils.getConnection(); )oy+-1dE
conn.setAutoCommit(false); y-mjfW`n
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +QeA*L$~
for(int i=0;i<CountCache.list.size();i++){ %+ytX]E
CountBean cb=(CountBean)CountCache.list.getFirst(); ;KT/;I
CountCache.list.removeFirst(); 8LUl@!4b
ps.setInt(1, cb.getCountId()); JV?d/[u,
ps.executeUpdate();⑴ ':]Hj8t_
//ps.addBatch();⑵ M"yOWD~s~
} o,{]<Sm
//int [] counts = ps.executeBatch();⑶ me$nP}%C&
conn.commit(); wxy@XN"/i+
}catch(Exception e){ -Sa-eWP
e.printStackTrace(); %uvA3N>
} finally{ $f+cd8j?o
try{ 2Q;rSe._`
if(ps!=null) { C=JS]2W2
ps.clearParameters(); x|)pZa
ps.close(); A[uB)wWsn
ps=null; C]Q}HI#G
} '3xK1Am
}catch(SQLException e){} W#\{[o
DBUtils.closeConnection(conn); 9V>C %I
} v1=N?8Hz1
} W=Mdh}u_I
public long getLast(){ aI1tG
return lastExecuteTime; uzIM?.H
} Tt4Q|"CJA
public void run(){ $3*y)Ny^
long now = System.currentTimeMillis(); ~/rKKc
if ((now - lastExecuteTime) > executeSep) { c[Z#q*Q
//System.out.print("lastExecuteTime:"+lastExecuteTime); G|TnvZ KX
//System.out.print(" now:"+now+"\n"); JH*fxG
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); B_>r|^Vh
lastExecuteTime=now; w!-MMT4y
executeUpdate(); 6VLo4bq 5
} ,h<xY>
else{ pUa\YO1J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yatZAl(B
} M5 ^qc
} }:(;mW8
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} z>)lp$
//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 P_)=sj!>-
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类写好了,下面是在JSP中如下调用。 NdrR+t^#
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<% N_d{E/
CountBean cb=new CountBean(); 2Sk"S/4}Z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LMuDda
CountCache.add(cb); ]~!CJ8d
out.print(CountCache.list.size()+"<br>"); 5F#FC89Kk
CountControl c=new CountControl(); yT[=!M
c.run(); -Ua&/Yd/}
out.print(CountCache.list.size()+"<br>"); Z/d {v:)
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