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: eT2*W$
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CountBean.java Lg"C ]
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/* KR7@[
* CountData.java K'#E3={tt
* +H$!a
* Created on 2007年1月1日, 下午4:44 =IAsH85Q
* \QU^>23
* To change this template, choose Tools | Options and locate the template under Xl74@wq
* the Source Creation and Management node. Right-click the template and choose (k np#
* Open. You can then make changes to the template in the Source Editor. 9'hv%A:\3
*/ };'\~g,1
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package com.tot.count; xq"Jy=4Q*
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/** u.rY#cS,-R
* yoAfc
* @author |p$spQ
*/ %'0TXr$
public class CountBean { 1>L(ul(qGF
private String countType; 4Vq%N
int countId; ,^icPQSwc
/** Creates a new instance of CountData */ 6"dD2WV/
public CountBean() {} @3kKJ
public void setCountType(String countTypes){ V`@>MOw^d
this.countType=countTypes; $['Bv
} <T[E=#
public void setCountId(int countIds){ F[ewn/]n
this.countId=countIds; %/updw#{B
} OT&k.!=
public String getCountType(){ O9:U8$*
return countType; Ali9pvE
} Xy%p "b<
public int getCountId(){ imiR/V>N
return countId; 7 I>G{
} ^]
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} WOh|U4vt
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CountCache.java ?.Pg\ur
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/* aM4k *|H?
* CountCache.java z2Z^~,i
* 7=(Hy\Q5xH
* Created on 2007年1月1日, 下午5:01 a'\o7_
* Mfv1Os:ST
* To change this template, choose Tools | Options and locate the template under 41SGWAd#:
* the Source Creation and Management node. Right-click the template and choose q{+_
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* Open. You can then make changes to the template in the Source Editor. 10H)^p%3+
*/ <oz!H[!
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package com.tot.count; *{+G=d
import java.util.*; `O'`eY1f
/** 4V~?.
* Y3O#Q)-j$
* @author -kbg\,PW
*/ %w7]@V Z
public class CountCache { I[n^{8gz
public static LinkedList list=new LinkedList(); U T="2*3gz
/** Creates a new instance of CountCache */ S]E.KLR?[;
public CountCache() {} ur$l Z0
public static void add(CountBean cb){ [|l?2j\
if(cb!=null){ yV^s,P1
list.add(cb); t'ZWc\
} H<1WbM:w
} S6[v;{xJ
} 36am-G
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CountControl.java @_z4tUP
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/* zz& ?{vJ
* CountThread.java MMj9{ou
* ,*7d
* Created on 2007年1月1日, 下午4:57 ;D$)P7k6
* _2N$LLbg
* To change this template, choose Tools | Options and locate the template under ~/*MY
* the Source Creation and Management node. Right-click the template and choose gJM`[x`T
* Open. You can then make changes to the template in the Source Editor. Y/7 $1k
*/ H@l}WihW
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package com.tot.count; 2+X\}s1vN
import tot.db.DBUtils; *E{2J:`
import java.sql.*; \_B[{e7z
/** XU"~h64]
* {GJ@psG*
* @author k?'B*L_Mzv
*/ i'\T R|qd
public class CountControl{ u7=U^}#
private static long lastExecuteTime=0;//上次更新时间 DY^;EZ!hb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AFAAuFE"
/** Creates a new instance of CountThread */ Xn{1 FJX/
public CountControl() {} ` Jdb ;
public synchronized void executeUpdate(){ ~s5SZK*
Connection conn=null; %HJK;
PreparedStatement ps=null; %plo=RF
try{ 7.`fJf?
conn = DBUtils.getConnection(); db6mfxi
conn.setAutoCommit(false); 1/"WD?a
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I(XOE$3
for(int i=0;i<CountCache.list.size();i++){ h*v8#\b$J_
CountBean cb=(CountBean)CountCache.list.getFirst(); _8E/)M
CountCache.list.removeFirst(); &%-73nYw
ps.setInt(1, cb.getCountId()); N ,z6y5Lu
ps.executeUpdate();⑴ Dtj&W<NXo
//ps.addBatch();⑵ G.UI|r/Kz
} mrw=T.
//int [] counts = ps.executeBatch();⑶ *M"}z
conn.commit(); Y0X-Zqk'
}catch(Exception e){ %VnbmoO
e.printStackTrace();
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} finally{ /bVoErf
try{
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if(ps!=null) { 4#lo$#
ps.clearParameters(); 9yfJVg
ps.close(); q|),`.eh\
ps=null; ^f(@gS}?
} V 0rZz
}catch(SQLException e){} }I>tO9M
DBUtils.closeConnection(conn); GP#aya
} 8e(\%bX
} L+q/){Dd(
public long getLast(){ VTH>
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return lastExecuteTime; >qF CB\(
} #Q
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public void run(){ sQ\8>[]
long now = System.currentTimeMillis(); $b mLu=9
if ((now - lastExecuteTime) > executeSep) { ,KFapz!
//System.out.print("lastExecuteTime:"+lastExecuteTime); tdu$pC6
//System.out.print(" now:"+now+"\n"); p }~qf
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1aTB%F
lastExecuteTime=now; :*KHx|Q
executeUpdate(); _FWBUZ;N
} U-3i
else{ [)TRTxFb
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .Fp4:
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} q?8|
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} \7'+h5a
} 0ik7v<:
//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 - RU=z!{
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类写好了,下面是在JSP中如下调用。 c.e2 M/
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<% NN?`"Fww
CountBean cb=new CountBean(); BGX.U\uc
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sdo[D
CountCache.add(cb); k1D@fiz
out.print(CountCache.list.size()+"<br>"); 3(,?S$>
CountControl c=new CountControl(); RtM8yar+sn
c.run(); #e$5d>j(
out.print(CountCache.list.size()+"<br>"); *vwbgJG! *
%>