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: ik?IC$*n3i
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CountBean.java ]3|h6KWq
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/* 3,i`FqQa
* CountData.java X`&Us
* LjGLi>kI~
* Created on 2007年1月1日, 下午4:44 COWlsca
* $l.8
* To change this template, choose Tools | Options and locate the template under o6 NmDv5
* the Source Creation and Management node. Right-click the template and choose ()8=U_BFz
* Open. You can then make changes to the template in the Source Editor. <l,e6K
*/ Vm@VhCsp
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package com.tot.count; (?uK
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/** [`h,Ti!m<
* #,lbM%a
* @author MwD+'5
*/ S]T71W<i
public class CountBean { ?vD<_5K;I
private String countType; OmK0-fa/
int countId; SmyJ@.L"
/** Creates a new instance of CountData */ .'+JA:3R
public CountBean() {} S=<
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public void setCountType(String countTypes){ xPT$d,~"
this.countType=countTypes; FB+nN5D/
} lr)MySsu#H
public void setCountId(int countIds){ ZFX}=?+
this.countId=countIds; @:'E9J06
} |C+
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public String getCountType(){ #Sg/
return countType; |%X_<Cpk
} #/`MYh=!W
public int getCountId(){ zYPvpZV/
return countId; }
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} hI<$lEB
} ;F, 6]LH!
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CountCache.java -xH3}K%
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/* (|6!pQ7
* CountCache.java z} VCiS0
*
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* Created on 2007年1月1日, 下午5:01 z;YX2G/{
* rA_r$X
* To change this template, choose Tools | Options and locate the template under '+^XL6$L
* the Source Creation and Management node. Right-click the template and choose 2qj0iRH#N<
* Open. You can then make changes to the template in the Source Editor. aQ 6T2bQ
*/ _#P5j#
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package com.tot.count; tnmz5Q
import java.util.*; z"sv,W
/** r_a1oO:
* qP%[nY
* @author 5=MM^$QG
*/ [nsTO5G$u
public class CountCache { _{i-.;K
public static LinkedList list=new LinkedList(); -cXVkH{
/** Creates a new instance of CountCache */ p_3VFKq>0
public CountCache() {} cz>`$Zz
public static void add(CountBean cb){ =PBJ+"DQs
if(cb!=null){ #DTBdBh?I
list.add(cb); !Nhq)i
} IP1{gMG
} C\[g>_J
} W9SEYkg
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CountControl.java n lvDMZ
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/* +qF,XJ2
* CountThread.java ZcN%F)htm
* E[_-s
* Created on 2007年1月1日, 下午4:57 #Bn7Cc
* E"H> [E
* To change this template, choose Tools | Options and locate the template under dI8y}EbE~
* the Source Creation and Management node. Right-click the template and choose lFM'F [-?-
* Open. You can then make changes to the template in the Source Editor. Lr(wS {
*/ z?_5fte`
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package com.tot.count; ZZ;V5o6E
import tot.db.DBUtils; +Mh 9Jf
import java.sql.*; QNm.8c$
/** x(88Y7o.t
* N(&/ Ud
* @author [Hp"a^~r|
*/ k{$Mlt?&-
public class CountControl{ G Q+g.{c
private static long lastExecuteTime=0;//上次更新时间 POUD*(DqNK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 B7qiCX}pD
/** Creates a new instance of CountThread */ [+$o`0q;N?
public CountControl() {} i_;]UvP
public synchronized void executeUpdate(){ !;C *Wsp}
Connection conn=null; .7GAGMNS
PreparedStatement ps=null; .hXdXY
try{ Y{#m=-h
conn = DBUtils.getConnection(); b<rJ@1qtJ
conn.setAutoCommit(false); qg@Wzs7c~
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); K_~SJbl
for(int i=0;i<CountCache.list.size();i++){ cvf#^Cu
CountBean cb=(CountBean)CountCache.list.getFirst(); A|U_$!cLZ
CountCache.list.removeFirst(); B\!.o=<h
ps.setInt(1, cb.getCountId()); U5wO;MA
ps.executeUpdate();⑴ bQM_rqjJGw
//ps.addBatch();⑵ NCysYmt
} e6?h4}[+*
//int [] counts = ps.executeBatch();⑶ u
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conn.commit(); {utIaMb]&v
}catch(Exception e){ @oL<Ioh
e.printStackTrace(); S}*%l)vfR
} finally{ %sLij*
try{ ]LhNP}c
if(ps!=null) { DV/P/1E
ps.clearParameters(); a<X<hxW:
ps.close(); M e
ps=null; Dy@f21+
} xcYYo'U
}catch(SQLException e){} fOyLBixR
DBUtils.closeConnection(conn); BqKh&m
} vb.`rj6
} >m{)shBX
public long getLast(){ +H
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return lastExecuteTime; e$^ O_e
} =p)Wxk
public void run(){ '
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long now = System.currentTimeMillis(); k iCg+@nT
if ((now - lastExecuteTime) > executeSep) { }A"%YDrNbG
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^4yFLqrC
//System.out.print(" now:"+now+"\n"); [sY>ac
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); @GGPw9a
lastExecuteTime=now; %h%^i
executeUpdate(); $fY4amX6Z
} K G~fDb
else{ cwxO|
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); c.PPVqx
} oY{r83h{
} @BN cIJk9
} l~M86 h
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 89'XOXl&1
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类写好了,下面是在JSP中如下调用。 E:&ga}h
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<% *Gm%Dn
CountBean cb=new CountBean(); (v^L2Po
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9)QvJ87e@7
CountCache.add(cb); T%xB|^lf
out.print(CountCache.list.size()+"<br>"); b&!7(Q[ sT
CountControl c=new CountControl(); >i4UU0m
c.run(); RCq_FY
out.print(CountCache.list.size()+"<br>"); #$Z|)i]w
%>