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: q]:+0~cz
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CountBean.java R0+v5E
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/* td4*+)'FY
* CountData.java ,HS\(Z
* Q6Q>b4 .3
* Created on 2007年1月1日, 下午4:44 K @"m0
* n|NI]Qi*
* To change this template, choose Tools | Options and locate the template under N J:]jd
* the Source Creation and Management node. Right-click the template and choose mB;W9[
* Open. You can then make changes to the template in the Source Editor. Q@%VJPLv.
*/ : Ey
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package com.tot.count; srx`"
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/** NAV}q<@v
* JI )+
* @author .{HU1/!
*/ ;3Fgy8T
public class CountBean { *r p@`W5
private String countType; k]Y+C@g
int countId; O(,Ezyx
/** Creates a new instance of CountData */ KQ?E]}rZ
public CountBean() {} JO5~Vj_"
public void setCountType(String countTypes){ &GwBxJ
this.countType=countTypes; *La*j3|:
} /4RKA!W
public void setCountId(int countIds){ ^SxB b,\
this.countId=countIds; Zi$a6
} 6VolTy@(x
public String getCountType(){ sq*R)cZ
return countType; 1mL--m'r
} B9iH+
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public int getCountId(){ T{]Tb=
return countId; L|S#(0
} 9/D+6hJ]:
} =NAL*4c+
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CountCache.java :~:(49l
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/* &AGV0{NMh]
* CountCache.java 6h}f^eJ:K,
* =/.[&DG
* Created on 2007年1月1日, 下午5:01 zi2hi9A
* #PoUCRRC
* To change this template, choose Tools | Options and locate the template under #1z}~1-
* the Source Creation and Management node. Right-click the template and choose h_?D%b~5
* Open. You can then make changes to the template in the Source Editor. KmEm
*/ \PU|<Ru.
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package com.tot.count; PAH;
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import java.util.*; W3{k{~
/** SWO$#X /
* (BMFGyE3
* @author M <"&$qZ$R
*/ p8[Z/]p
public class CountCache { T*J]e|aF
public static LinkedList list=new LinkedList(); 0Vh|UJ'&7
/** Creates a new instance of CountCache */ hX$k8 o0
public CountCache() {} -}9ZZ#K
public static void add(CountBean cb){ ff?:_q+.N
if(cb!=null){ #p*{p)]HiA
list.add(cb); &Dqg<U
} +_06{7@h
} vNd4Fn)H
} v)d\
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CountControl.java ~k+-))pf
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/* D"bLJj/!
* CountThread.java 8D)*~C'85E
* ;,JCA#
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* Created on 2007年1月1日, 下午4:57 53=s'DZ
* t 4{{5U'\
* To change this template, choose Tools | Options and locate the template under @/`b:sv&*
* the Source Creation and Management node. Right-click the template and choose j*q]-$ 2E
* Open. You can then make changes to the template in the Source Editor. fwf]1@#
*/ 6@ET3v
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package com.tot.count; 2y,NT|jp
import tot.db.DBUtils; +<Uc42i7n
import java.sql.*; n_v|fxF1
/** +*DXzVC
* hCc_+/j|
* @author (VWTYG7
*/ ts{Tk5+
public class CountControl{ ,N<xyx.
private static long lastExecuteTime=0;//上次更新时间 y_Bmd
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X[(u]h`
/** Creates a new instance of CountThread */ nr!kx)j
public CountControl() {} ds4ERe /
public synchronized void executeUpdate(){ 0{@E=}}h
Connection conn=null; {O]Cj~}
PreparedStatement ps=null; Z[FSy-;"
try{ n>+M4Zb
conn = DBUtils.getConnection(); yw{GO([ZQ
conn.setAutoCommit(false); 7-'!XD!
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^ bexXYh
for(int i=0;i<CountCache.list.size();i++){ mG1=8{o^
CountBean cb=(CountBean)CountCache.list.getFirst(); Mf<Pms\F
CountCache.list.removeFirst(); ES(b#BlrP/
ps.setInt(1, cb.getCountId()); H8mmmt6g
ps.executeUpdate();⑴ :&/'rMi<T
//ps.addBatch();⑵ TC<_I0jCh
} "/(J*)%{
//int [] counts = ps.executeBatch();⑶ ]pzf{8%
conn.commit(); * A@~!@XE4
}catch(Exception e){ (c axl^=
e.printStackTrace(); bsmZR(EnU
} finally{ TXv3@/>ZlG
try{ N*f?A$u/I
if(ps!=null) { ^}a..@|%W
ps.clearParameters(); l <Tkg9
ps.close(); P@`@?kMU
ps=null; ?.LS_e_0
} VWj]X7v
}catch(SQLException e){} :3gtc/p t>
DBUtils.closeConnection(conn); yS0!#AG
} ~dkS-6q~Q
} f1rP+l-C<
public long getLast(){ ,ZHIXylZ
return lastExecuteTime; >OgA3)X
} (OLj E]9;
public void run(){ wI'T Je,
long now = System.currentTimeMillis(); _U?
if ((now - lastExecuteTime) > executeSep) { /vYuwaWG=
//System.out.print("lastExecuteTime:"+lastExecuteTime); jL8.*pfv
//System.out.print(" now:"+now+"\n"); g=0`^APql
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,,sKPj[
lastExecuteTime=now; >=G;rs
executeUpdate(); e4fh<0gX
} `aD~\O
else{ E z?O
gE{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?NOc]'<(G
} S1p4.qJ
} F{WV}o=MY
} U>H"N1
//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 RP9 #P&Qk
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类写好了,下面是在JSP中如下调用。 *|{1`{8n
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<% wj!YYBH
CountBean cb=new CountBean(); O`j1~o<{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XD%@Y~>+
CountCache.add(cb); w<#/ngI2
out.print(CountCache.list.size()+"<br>"); OyH>N/
CountControl c=new CountControl(); Y&!-VW
c.run(); R&KFF'%
out.print(CountCache.list.size()+"<br>"); o-a\T
%>