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: wzcv[C-x
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CountBean.java 2_Zn?#G8dl
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/* iQgr8[
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* CountData.java +(`.pa z@
* %WqUZ+yy
* Created on 2007年1月1日, 下午4:44 HcV,r,>e
* &o&}5Aba9
* To change this template, choose Tools | Options and locate the template under J<9})
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* the Source Creation and Management node. Right-click the template and choose #%/Jr 52<
* Open. You can then make changes to the template in the Source Editor. mi@uX@ #
*/ iszVM
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package com.tot.count; 07\]8^/G
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/** .eCUvX`$
* 9niffq)h
* @author
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*/ %6&c3,?U\n
public class CountBean { 5kHU'D
private String countType; A6xN6{R!
int countId; @udc/J$
/** Creates a new instance of CountData */ =(bTS n
public CountBean() {} \_)mWK,h
public void setCountType(String countTypes){ p77=~s
this.countType=countTypes; '*`1uomeo
} zQB1C
public void setCountId(int countIds){ oHF,k
this.countId=countIds; 4F!%mMq
} <2LUq@Pg
public String getCountType(){ jS|jPk|I.
return countType; ,o0[^-b<
} s-F3(mc(
public int getCountId(){ _Om5wp=:
return countId; R-2Abyts2
} d7Z$/ $
} a,:Nlr3
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CountCache.java _+Uf5,.5yU
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/* v5FfxDvw
* CountCache.java mAe)Hy %
* \=(U tro
* Created on 2007年1月1日, 下午5:01 bE jQMlb
* m$g{&
* To change this template, choose Tools | Options and locate the template under =7S\-{
* the Source Creation and Management node. Right-click the template and choose ;9)=~)
* Open. You can then make changes to the template in the Source Editor. _z#S8Y
*/ mhNgXp)_56
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package com.tot.count; }To-c'
import java.util.*;
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/** z:08;}t
* D e$K
* @author )$O'L7I n&
*/ 3)l<'~"z<
public class CountCache { o%h[o9i
public static LinkedList list=new LinkedList(); #BI6+rfv|
/** Creates a new instance of CountCache */ , lBHA+@
public CountCache() {} h0l_9uI
public static void add(CountBean cb){ = d !YM6G
if(cb!=null){ C`aUitL}
list.add(cb); OjK+`D_C
} Tq%##
} G.^^zmsM`
} T1RICIf1F
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CountControl.java bGik~
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/* Wf&i{3z[
* CountThread.java Fn;Gq-^7@
* W)`H(J
* Created on 2007年1月1日, 下午4:57 jVSU]LU E
* h~#.s*0.F
* To change this template, choose Tools | Options and locate the template under T
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* the Source Creation and Management node. Right-click the template and choose (V`ddP-
* Open. You can then make changes to the template in the Source Editor. ~b9fk)z!
*/ .zJZ*\2ob
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package com.tot.count; &Z+.FTo
import tot.db.DBUtils; NDG?Xs [2
import java.sql.*; "ZG2olOqLI
/** [t]q#+Zs
* n%{oFTLCo
* @author *#B"%;Ln
*/ )2bbG4:N
public class CountControl{ D ~NWP%H
private static long lastExecuteTime=0;//上次更新时间 B\>3[_n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _9z+xl
/** Creates a new instance of CountThread */ Fz]!2rt
public CountControl() {} M:%Ll3
public synchronized void executeUpdate(){ XE;aJ'kt
Connection conn=null; rTeADu_vf
PreparedStatement ps=null; "':SWKuMx
try{ px^brzLQo
conn = DBUtils.getConnection(); oN(F$Nvk
conn.setAutoCommit(false); ;!<@Fm9W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f'u[G?C
for(int i=0;i<CountCache.list.size();i++){ ^>h2.AJ
CountBean cb=(CountBean)CountCache.list.getFirst(); 21~~ =+)X
CountCache.list.removeFirst(); .1[pO_
ps.setInt(1, cb.getCountId()); I!~3xZ
ps.executeUpdate();⑴ QaAMiCZFR
//ps.addBatch();⑵ ^K!R4Y4t
} (FOJHjtkM
//int [] counts = ps.executeBatch();⑶ :;o?d&C
conn.commit(); tsf!Q
}catch(Exception e){ a&gf0g;@I
e.printStackTrace(); zi,":KDz#
} finally{ V V Aw y6
try{ TA+/35^?
if(ps!=null) { <}AmzeHr+
ps.clearParameters(); OJ}aN>k
ps.close(); mtNB09E(
ps=null; 62>/0_m5
} PjU.4aZ
}catch(SQLException e){} *G,r:Bnb
DBUtils.closeConnection(conn); kk/vgte-)e
} cqb]LC
} z9^_5la#
public long getLast(){ 2Zi&=Zj"
return lastExecuteTime; `,6^eLU
} )h;zH,DA[3
public void run(){ &0J/V>k
long now = System.currentTimeMillis(); 6X$iTJ[\x
if ((now - lastExecuteTime) > executeSep) { 15!b]':
//System.out.print("lastExecuteTime:"+lastExecuteTime); `wNJ*`
//System.out.print(" now:"+now+"\n"); l78:.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); A
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lastExecuteTime=now; "C9.pdP\8
executeUpdate(); [,mcvO;
} Ht%O9v
else{ \MtdT[*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); E=~Ahkg
} ZmJHLn[B
} |1Ko5z
} q^b_'We_9
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 z0 _/JwJn
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类写好了,下面是在JSP中如下调用。 ~Nl`Zmn(A|
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<% K?mly$
CountBean cb=new CountBean(); QK`2^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "4i_}
CountCache.add(cb); H3qL&xL
out.print(CountCache.list.size()+"<br>"); :,=Z)e
CountControl c=new CountControl(); yykyvy
c.run(); 7:&a,nU
out.print(CountCache.list.size()+"<br>"); 8R.`*
%>