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: U0=]
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CountBean.java _,q) hOI
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/* )64@2~4y
* CountData.java #u2J;9P
* nv)2!mAh\
* Created on 2007年1月1日, 下午4:44 +U_=*"@|
* %509\;el
* To change this template, choose Tools | Options and locate the template under 3Uqr,0$p
* the Source Creation and Management node. Right-click the template and choose rJFc({ 0
* Open. You can then make changes to the template in the Source Editor. 0ph{
*/ HfcL%b%G8
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package com.tot.count; ANvR i+ _
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/** ~jK{ ,$:=
* dX\.t<
* @author m1n.g4Z&*
*/ ~UyV<
public class CountBean { fKp#\tCc y
private String countType; )v]/B+
int countId; sBu=e7
/** Creates a new instance of CountData */ )Y]{HQd
public CountBean() {} >a"Z\\dF
public void setCountType(String countTypes){ >:zK?(qu,N
this.countType=countTypes; h\7fp.
} _tSAI
public void setCountId(int countIds){ ,REJt
this.countId=countIds; .P.z B}0=
} J~B<7O<?!1
public String getCountType(){ ?gJOgsHJP
return countType; bfA=3S"0
} p(PMZVV`
public int getCountId(){ ;2@BO-3K
return countId; HODz*pI
} 6}4'E
} 0ge$ p,
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CountCache.java ikSF)r;*t
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/* PlF87j (
* CountCache.java I/M _p^
* H~GQ;PhRx
* Created on 2007年1月1日, 下午5:01 8%%f%y
* Q?8R[i
* To change this template, choose Tools | Options and locate the template under 6lkl7zm
* the Source Creation and Management node. Right-click the template and choose YFE&r
* Open. You can then make changes to the template in the Source Editor. af#pR&4}
*/ O=v#{ [
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package com.tot.count; CNQC^d\ h
import java.util.*; h@:TpE+N
/** cC o`~7rE
* UbEb&9}
* @author v^)bhIPe;
*/ %STliJ
public class CountCache { vo\fUT@k
public static LinkedList list=new LinkedList(); Vw#_68EybM
/** Creates a new instance of CountCache */ 3uZJ.Fb
public CountCache() {} 1z&Ly3
public static void add(CountBean cb){ `W dD8E
if(cb!=null){ aO@7O*
list.add(cb); GuGOePV
} #VB')^d<U
} AK=
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} >$ NDv
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CountControl.java VOc8q-hK
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/* #6AFdNy
* CountThread.java j
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* |,#t^'S!
* Created on 2007年1月1日, 下午4:57 rsF\JQk
* yu6`66h)
* To change this template, choose Tools | Options and locate the template under ZunCKc
* the Source Creation and Management node. Right-click the template and choose VtzI9CD
* Open. You can then make changes to the template in the Source Editor. vKq^D(&cl
*/ |o2sbLp
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package com.tot.count; (RUT{)p[
import tot.db.DBUtils; +2K :qvzZ
import java.sql.*; i^_#%L
/** q}/WQ]p} <
* uKz,SqX
* @author /,MJq#@K
*/ DUL4noq{
public class CountControl{ #'-Sh7ycW
private static long lastExecuteTime=0;//上次更新时间 UK$ms~H
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `6[I^qG".
/** Creates a new instance of CountThread */ ^ K7ic,{
public CountControl() {} %.<H=!$
public synchronized void executeUpdate(){ JOb*-q|y
Connection conn=null; j:}J}P
PreparedStatement ps=null; :}h>by=
try{ rQOWLg!"
conn = DBUtils.getConnection(); t~e<z81p
conn.setAutoCommit(false); ~_9n .C
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); b{d4xU8'
for(int i=0;i<CountCache.list.size();i++){ n:0}utU4
CountBean cb=(CountBean)CountCache.list.getFirst(); bn(`O1r[(
CountCache.list.removeFirst(); JXixYwm
ps.setInt(1, cb.getCountId()); 2+cNo9f
ps.executeUpdate();⑴ ik"sq}u_]E
//ps.addBatch();⑵ l"q1?kaVg
} /erN;Oo%<
//int [] counts = ps.executeBatch();⑶ Dy]I8_
conn.commit(); >6~k9>nDb<
}catch(Exception e){ RrhT'':[
e.printStackTrace(); :d0Y%vl
} finally{ /wxE1][.
try{ hY*0aZ|(
if(ps!=null) { &n[~!%(
ps.clearParameters(); i\4hR?
ps.close(); KJ?y@Q
ps=null; +B'8|5tPX
} .fi/I
}catch(SQLException e){} CvPioi
DBUtils.closeConnection(conn); ( 7ws{)
} ^pS+/ZSi^
} !PMU O\y
public long getLast(){ ^9_UUzf\
return lastExecuteTime; c(U
} [w0/\]o
public void run(){ Z2Zq'3*
long now = System.currentTimeMillis(); 2[B4f7
if ((now - lastExecuteTime) > executeSep) { SR^_cpZoi
//System.out.print("lastExecuteTime:"+lastExecuteTime); kF{*(r=.o
//System.out.print(" now:"+now+"\n"); &(zfa&j|
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); aZet0?Qr
lastExecuteTime=now; Aj9Ji"18za
executeUpdate(); x$wd
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} [xfaj'j=@
else{ ewuXpv%vwW
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ="%W2
} !@I}mQ ~
} Uu"0rUzt
} QN>7~=`
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 rVtw-[p
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类写好了,下面是在JSP中如下调用。 .6m "'m0;
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<% T*I?9d{k
CountBean cb=new CountBean(); tu>{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iB1i/l
CountCache.add(cb); RGIoI]_
out.print(CountCache.list.size()+"<br>"); BPqGJ7@
CountControl c=new CountControl(); [ U8$HQ+x
c.run(); 6*nAo8gl
out.print(CountCache.list.size()+"<br>"); "BKeot[""p
%>