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: (N5"'`NZA
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CountBean.java y (=0
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/* $)'LbOe
* CountData.java qos/pm$&i
* \\35}
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* Created on 2007年1月1日, 下午4:44 XnRm9%
* ^MVOaV65
* To change this template, choose Tools | Options and locate the template under o5G]|JM_
* the Source Creation and Management node. Right-click the template and choose ^}lL@Bd|
* Open. You can then make changes to the template in the Source Editor. $SfY<j,R
*/ c*R18,5-
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package com.tot.count; [~?6jnp
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/** IEWl
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* ,2P/[ :
* @author ^Zlbs
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*/ m;PTO$--
public class CountBean { ^BP4l_rO9
private String countType; 1+Vei<H$
int countId;
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/** Creates a new instance of CountData */ ${`q!
public CountBean() {} &?k`rF9
public void setCountType(String countTypes){ MI~QXy,
this.countType=countTypes; (A-Uo
} y|3!E>Up
public void setCountId(int countIds){ Pt'=_^Io
this.countId=countIds; etk|%%J
} \!k\%j9
public String getCountType(){ ?28)l
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return countType; In*0.
} nFwdW@E9
public int getCountId(){ 01IfvK
return countId; S4OOm[8
} )2r_EO@3HP
} E cd~H+
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CountCache.java HN<e)E38
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/* <iM}p^jX9
* CountCache.java >Fc=F#tA9
* wE_#b\$=b
* Created on 2007年1月1日, 下午5:01 Y>K3.*.
* ae]
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* To change this template, choose Tools | Options and locate the template under ~<=wTns!
* the Source Creation and Management node. Right-click the template and choose 1VG7[#Zy
* Open. You can then make changes to the template in the Source Editor. qox@_
*/ lUHpGr|U%
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package com.tot.count; q]z%<`.9*
import java.util.*;
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/** s#V:!
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* 6s&%~6J,
* @author hgF4PdO1e
*/ |dk9/xdX
public class CountCache { H,U qU3b3
public static LinkedList list=new LinkedList(); _<;westq
/** Creates a new instance of CountCache */ 08;t%[R
public CountCache() {} > 0NDlS%Q:
public static void add(CountBean cb){ 98t|G5
if(cb!=null){ qvN 5[rb
list.add(cb); "?Xb$V7
} REKv&^FLN
} !\N|$-M
} n ,CMGe^:
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CountControl.java 6R%NjEW:
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/* DX@*lM
* CountThread.java EyPF'|Qtn
* ~JxAo\2i
* Created on 2007年1月1日, 下午4:57 &oqzQ+H
* /*)
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* To change this template, choose Tools | Options and locate the template under ^1w*$5YI
* the Source Creation and Management node. Right-click the template and choose YNWAef4
* Open. You can then make changes to the template in the Source Editor. '5m`[S-IU
*/ 'P<T,:z?
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package com.tot.count; p+d?k"WN?
import tot.db.DBUtils; k6W
[//
import java.sql.*; ys$X!Ep
/** F5;x>;r
* <ooRpn
* @author *[[TDduh&
*/ <)$b=z
public class CountControl{ !Typ_Cs
private static long lastExecuteTime=0;//上次更新时间 vaUUesytt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0`l(c
/** Creates a new instance of CountThread */ E7UYJ)6]
public CountControl() {} Qg4g(0E@
public synchronized void executeUpdate(){ }@S''AA\
Connection conn=null; :6X?EbXhK
PreparedStatement ps=null; L
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try{ (3M7 RpsL@
conn = DBUtils.getConnection(); U `<?~Bz
conn.setAutoCommit(false); \%011I4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Fl&Z}&5p
for(int i=0;i<CountCache.list.size();i++){ ^\zf8kPti
CountBean cb=(CountBean)CountCache.list.getFirst(); Um\_G@
CountCache.list.removeFirst(); \LZVazXD
ps.setInt(1, cb.getCountId()); -
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ps.executeUpdate();⑴ SRf.8j
//ps.addBatch();⑵ !]z6?kUK
} S`?cs^?
//int [] counts = ps.executeBatch();⑶ gw);b)&mx
conn.commit(); 9Wi+7_)
}catch(Exception e){ jFMf=u&U
e.printStackTrace(); +XN/ bT
} finally{ Y>: e4Q
try{ t=$Hv
if(ps!=null) { ON/U0V:v
ps.clearParameters(); rq>OmMQ67
ps.close(); -{'WIGm
ps=null; FlQ(iv)P
} }c~o3t(7`b
}catch(SQLException e){} b];? tP
DBUtils.closeConnection(conn); "G3zl{?GP
} B'"RKs]
} S;FgS:;
public long getLast(){ 8h| 9;%
return lastExecuteTime; O'}
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} X0QLT:J b
public void run(){ %;{Ro)03
long now = System.currentTimeMillis(); UjI-<|
if ((now - lastExecuteTime) > executeSep) { SYsbe 5j
//System.out.print("lastExecuteTime:"+lastExecuteTime); )0 W-S9e<
//System.out.print(" now:"+now+"\n"); urK[v
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =-U8^e_Y
lastExecuteTime=now; YKT=0
executeUpdate(); ZhpbbS
} nY[]k p@
else{ XLNR%)l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); k^Q>
} Lu@'Ee!>G
} iCrLZ"$M
} ~9KxvQzt
//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 1-M\K^F
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类写好了,下面是在JSP中如下调用。 PRE\2lLY
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<% 6#rj3^]
CountBean cb=new CountBean(); j >wT-s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `K^j:fE7n
CountCache.add(cb); %[9d1F3
out.print(CountCache.list.size()+"<br>"); L)Iv]u
CountControl c=new CountControl(); V!94I2%#x
c.run(); <(U:v
out.print(CountCache.list.size()+"<br>"); :UgCP ~Y
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