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: Rv=DI&K%n
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CountBean.java dXmV@ Noo
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/* #Mh{<gk%ax
* CountData.java Rj^7#,993
* t)` p@]j
* Created on 2007年1月1日, 下午4:44 m9Ax\lf
* OFA{
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* To change this template, choose Tools | Options and locate the template under -;^;2#](g
* the Source Creation and Management node. Right-click the template and choose nSS>\$
* Open. You can then make changes to the template in the Source Editor. P`
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*/ [r(Qs|
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package com.tot.count; 7KU~(?|:h
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/** iZaeoy
* @}WNKS&m
* @author blGf!4H
*/ *I0Tbc
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public class CountBean { J1bA2+5.*e
private String countType; $(ewk):
int countId; ^(ScgoXva
/** Creates a new instance of CountData */ ;6ky5}z
public CountBean() {} ({4]
public void setCountType(String countTypes){ 9:5:`'b
this.countType=countTypes; "
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} 'Gjq/L/x
public void setCountId(int countIds){ &rp!%]+xAM
this.countId=countIds; RPVT*`o
} P"1 S$oc
public String getCountType(){ [8"oj hdV
return countType; oBA`|yW{U
} D==Mb~
public int getCountId(){ FXV`9uq}Z
return countId; $J.T$0pFa
} k@V#HC{t
} I^D0<lHl~
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CountCache.java 'CXRG$D
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/* 1j0 -9Kg'
* CountCache.java z>;$im
* H6&7\Wbk
* Created on 2007年1月1日, 下午5:01 Gih[i\%Q
* _tAQ=eBO
* To change this template, choose Tools | Options and locate the template under &-%X:~|:X
* the Source Creation and Management node. Right-click the template and choose P}V=*g
* Open. You can then make changes to the template in the Source Editor. Y#FO5O%W
*/ +E/y ~s
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package com.tot.count; ,LZX@'5
import java.util.*; =p@8z
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/** B6]<G-
* H2;X
* @author HSN8O@dy
*/ 8!mc@$Z
public class CountCache { I;7nb4]AmF
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ BByCMY
public CountCache() {} a{SBCy
public static void add(CountBean cb){ B&Y_2)v
if(cb!=null){ 2 -Xdoxw
list.add(cb); #eK=
} ow6*Xr8eQ
} ]JE TeZ^/
} Z{R[Wx
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CountControl.java %+-C3\'
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/* w~Ff%p@9
* CountThread.java 5Y\!pf7SQ|
* f[sF:f(zI
* Created on 2007年1月1日, 下午4:57 >^$2f&z
* DNkWOY#{
* To change this template, choose Tools | Options and locate the template under eKN$jlg
* the Source Creation and Management node. Right-click the template and choose Bfr'Zdw
* Open. You can then make changes to the template in the Source Editor. iWLa> z|,
*/ nmFC%p)4
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package com.tot.count; 06*rWu9P3
import tot.db.DBUtils; .>pgU{C`!
import java.sql.*; g~S)aU\:,
/** kforu!C
* @kFu*"
* @author ~D[?$`x:
*/ re &E{
public class CountControl{ 1l8Etp&<
private static long lastExecuteTime=0;//上次更新时间 7v7G[n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xSK~s
/** Creates a new instance of CountThread */ }fR,5|~X
public CountControl() {} nZy X_J,Vd
public synchronized void executeUpdate(){ sC"}8+[)S3
Connection conn=null; %XTcP2pRJ
PreparedStatement ps=null; 2Y!S_Hw8
try{ ?!VIS>C(
conn = DBUtils.getConnection(); v$wBxCY
conn.setAutoCommit(false); q<#>HjC
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vuQ%dDxI
for(int i=0;i<CountCache.list.size();i++){ -e u]:4
CountBean cb=(CountBean)CountCache.list.getFirst(); \5)h tL1F
CountCache.list.removeFirst(); :_kAl? eJ
ps.setInt(1, cb.getCountId()); $gpG%Qj
ps.executeUpdate();⑴ fyWO
//ps.addBatch();⑵ F^k.is
} SP]IUdE\
//int [] counts = ps.executeBatch();⑶ p4K.NdUH
conn.commit(); L,,*gK
}catch(Exception e){ zTbVp8\pI
e.printStackTrace(); C0*@0~8$9
} finally{ 6t'l(E +
try{ f~{}zGTM:
if(ps!=null) { cbYLU\!
ps.clearParameters(); 9#d+RT
ps.close(); VOTv?Vf
ps=null; 7OCwG~_^
} ;Xvp6.:
}catch(SQLException e){} _c$9eAe
DBUtils.closeConnection(conn); '1^B+m
} X^9d/}uTa
} sOCs13A"
public long getLast(){ WY:&ugGx
return lastExecuteTime; in`aGFQO
} &sXRN&Fp
public void run(){ <#GB[kQa
long now = System.currentTimeMillis(); s@hRqGd:
if ((now - lastExecuteTime) > executeSep) { D}C,![
//System.out.print("lastExecuteTime:"+lastExecuteTime); '_k+WH&
//System.out.print(" now:"+now+"\n"); :!a2]-D}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); '})0!g<Y
lastExecuteTime=now; P|tNL}2`;
executeUpdate(); `+:.L>5([
} !HeSOzN
else{ ^u}L;`L
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7R#+Le)
} _p-t<ytnh
} vsWHk7 9
} hN2:d1f0
//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 wkqX^i7ls
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类写好了,下面是在JSP中如下调用。 ?Iyo9&1&
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<% ps
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CountBean cb=new CountBean(); 'J&f%kx"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v[plT2"s
CountCache.add(cb); mGUO6>g
out.print(CountCache.list.size()+"<br>"); +Q=1AXe
CountControl c=new CountControl(); RB* J=
c.run(); /2EHv.e`
out.print(CountCache.list.size()+"<br>"); 1i:|3PA~
%>