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: q4ej7T8
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CountBean.java EtA ,ow
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/* @1)C3(=A
* CountData.java 7kQ,D,c'
* -|_io,eL;
* Created on 2007年1月1日, 下午4:44 Fo&ecWhw
* kud2O>>
* To change this template, choose Tools | Options and locate the template under &A~(9IV
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. t2&}
*/ 73(5.'F
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package com.tot.count; dhI+_z
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/** f9J]-#I if
* l[{Ci|4
* @author o)Nm5g
*/ {aWfD XB1
public class CountBean { ~Ec@hz]js
private String countType; tq5o
int countId; +yIO
/** Creates a new instance of CountData */ xwu,<M
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public CountBean() {} UJGmaE
public void setCountType(String countTypes){ a8r+G]Z
this.countType=countTypes; StM)lVeF
}
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public void setCountId(int countIds){ DP4l
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this.countId=countIds; 0/?=FM>
} k{pn~)xg
public String getCountType(){ nokMS
return countType; LX iis)1
} KS(Ms*k;'
public int getCountId(){ ,ikn%l#cm
return countId; /BfCh(B
}
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} ~n!7 ?4%U
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CountCache.java e+P|PW
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/* ,v*<yz/
* CountCache.java ED
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* d)jX%Z$LC
* Created on 2007年1月1日, 下午5:01 o$bD?Zn
* dG'5: ,n/
* To change this template, choose Tools | Options and locate the template under h_ J|uu
* the Source Creation and Management node. Right-click the template and choose j=TGe
* Open. You can then make changes to the template in the Source Editor. XX'Rv]T
*/ KiG/XnS
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package com.tot.count; ]e]l08
import java.util.*; Y([vma>U]
/** >l|dLyiae
* '8bT9
* @author `(?x@Y>.Ht
*/ E[E[Za^Y
public class CountCache { (_O_zu8_
public static LinkedList list=new LinkedList(); <y5f[HjLy
/** Creates a new instance of CountCache */ B~2\v%J
public CountCache() {} *ocbV`
public static void add(CountBean cb){ )t$|'c}
if(cb!=null){ k!6wVJ|_Y
list.add(cb); iv62Fs'
} a
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} {,rVA(I@
} <sq@[\l}a
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CountControl.java O%(k$fvM
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/* *S@0o6v
* CountThread.java Q.G6y,KR
* sj?7}(s
* Created on 2007年1月1日, 下午4:57 4l*4wx""v
* tgbr/eCoU
* To change this template, choose Tools | Options and locate the template under q"[8u ]j
* the Source Creation and Management node. Right-click the template and choose vc_ 5!K%[
* Open. You can then make changes to the template in the Source Editor. $xf{m9 8
*/ s~(iB{-
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package com.tot.count; ^#4?v^QNh
import tot.db.DBUtils; f}cz_"o4
import java.sql.*; v*7lJNN.
/** 058+_xX
* V3u[{^^f
* @author
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*/ hd2 X/"
public class CountControl{ @{Q[M3l
private static long lastExecuteTime=0;//上次更新时间 v@0lTl_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 '}{J;moB
/** Creates a new instance of CountThread */ ,/;mK_6
public CountControl() {} _/_1:ivY8
public synchronized void executeUpdate(){ ec4jiE
Connection conn=null; u,e(5LU
PreparedStatement ps=null; MhNDf[W>
try{ _Z|s!~wdz
conn = DBUtils.getConnection(); @JWoF^U
conn.setAutoCommit(false); j3bTa|UdT
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yVyh'd:Ik
for(int i=0;i<CountCache.list.size();i++){ oOhm`7iy
CountBean cb=(CountBean)CountCache.list.getFirst(); [UVxtM J
CountCache.list.removeFirst(); QJ`#&QRp
ps.setInt(1, cb.getCountId()); n7"e 79
ps.executeUpdate();⑴ :4"SJ
//ps.addBatch();⑵ VJX{2$L
} _,i]ra{%
//int [] counts = ps.executeBatch();⑶ oVsj
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conn.commit(); FKd5]am
}catch(Exception e){ L)'JkX J
e.printStackTrace(); u:pdY'`"#
} finally{ 9lA@ K[
try{ P nsQ[}.
if(ps!=null) { oQC* d}_E}
ps.clearParameters(); l[O!_bH
ps.close(); 2roPZj
ps=null; k[l+~5ix
} qwu++9BM
}catch(SQLException e){} ^A^,/3
DBUtils.closeConnection(conn); `~hAXnQK=
} 8x
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} BYEqTwhT&
public long getLast(){ *J!oV0#1
return lastExecuteTime; \`#;J?Y|`F
} ,epKt(vl
public void run(){ {}?s0U$5
long now = System.currentTimeMillis(); Q/6T?{\U7
if ((now - lastExecuteTime) > executeSep) { U&PAs
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//System.out.print("lastExecuteTime:"+lastExecuteTime); JEX{jf
//System.out.print(" now:"+now+"\n"); JbG\Ywi0]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); GdavCwJ
lastExecuteTime=now; jK#y7E
executeUpdate(); .*>LD
} +(5 H$O{h
else{ V; 1r
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rm>;B
*;
} v#.FK:u}
} *$x/(!UE
} >\K<q>*
//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 /d5_-AB(v
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类写好了,下面是在JSP中如下调用。 4@|K^nT`
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<% .b]g#Du=
CountBean cb=new CountBean(); Tk9*@kqv
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Phl't~k
CountCache.add(cb); k0?4vA
out.print(CountCache.list.size()+"<br>"); _Kx
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CountControl c=new CountControl(); L1`^~m|
c.run(); 0/<}.Z]
out.print(CountCache.list.size()+"<br>"); [kzcsJ'/e
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