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: "Ar|i8^G3
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CountBean.java 7F2:'3SQ
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/* m'G=WO*%
* CountData.java W! |_ hL
* U![$7k>,pr
* Created on 2007年1月1日, 下午4:44 Y[VXx8"p
* J_XkQR[Y
* To change this template, choose Tools | Options and locate the template under t\2-7Ohj6
* the Source Creation and Management node. Right-click the template and choose ncVt(!c,e
* Open. You can then make changes to the template in the Source Editor. a3:45[SO4e
*/ #PC*l\
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package com.tot.count; I"8Z'<|/\q
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/** Jp8,s%
* ?J+*i
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* @author V'za,.d-
*/ "N EKz
public class CountBean { Gw6Odj
private String countType; ^[+2P?^K
int countId; Xrc{wDn
/** Creates a new instance of CountData */ 5,O:"3>c
public CountBean() {} WU/5i 8
public void setCountType(String countTypes){
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this.countType=countTypes; 8{%&P%vf
} !6#.%"{-
public void setCountId(int countIds){ :.{d,)G
this.countId=countIds; gtY7N>e
} WhFE{-!gX
public String getCountType(){ 3c:fYE
return countType; 3UQBIrQ
} =:TQ_>$Nc2
public int getCountId(){ xvWP^Qkb
return countId; !af;5F
} >r4BI}8SK<
} )5x$J01S
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CountCache.java ^|!\IzDp
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/* or)fx/ %h
* CountCache.java "HJQAy?W
* O!F"w!5@
* Created on 2007年1月1日, 下午5:01 mEb`ET|
* HuxvIg
* To change this template, choose Tools | Options and locate the template under K)\D,5X^
* the Source Creation and Management node. Right-click the template and choose ZxDh!_[s
* Open. You can then make changes to the template in the Source Editor. @}%kSn5y:
*/ t?;=\%^<
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package com.tot.count; e&mTaCLG
import java.util.*; V Kc`mE
/** N>@.(f&w
* ((BdT:T\_
* @author &k(tDP
*/ h`tf!M D]
public class CountCache {
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public static LinkedList list=new LinkedList(); 1@+&6UC
/** Creates a new instance of CountCache */ h}+Gz={Q^
public CountCache() {} Xs2B:`,hh
public static void add(CountBean cb){ /sSif0I24
if(cb!=null){ nxuR^6Ai
list.add(cb); On@p5YRwW
} Lf Y[Z4
} s21)*d
} | fn%!d`2
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CountControl.java A<[w'"
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/* (B].ppBii
* CountThread.java u/`x@u
* HDhG1B"NL
* Created on 2007年1月1日, 下午4:57 uVw|jj
* iz`ys.Fu
* To change this template, choose Tools | Options and locate the template under *MN("<A_
* the Source Creation and Management node. Right-click the template and choose z9zo5Xc=
* Open. You can then make changes to the template in the Source Editor. O(T6Y80pU
*/ m&Y?]nbq
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package com.tot.count; W6yz/{Rf
import tot.db.DBUtils; WjBtL52
import java.sql.*; b$B-LvHd1
/** S|BS;VY
* T%2%*oa
* @author 4 ..V
*/ dQ Ao~]B
public class CountControl{ pf_`{2.\uO
private static long lastExecuteTime=0;//上次更新时间 x=44ITe1n[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Z^yn S
/** Creates a new instance of CountThread */ A~wyn5:_
public CountControl() {} X*M-- *0q'
public synchronized void executeUpdate(){ ">R`S<W
Connection conn=null; RSF@ Oo{
PreparedStatement ps=null; /.m}y$@GV
try{ m^a0JR}u9
conn = DBUtils.getConnection(); mp0!S
conn.setAutoCommit(false); #U/L8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I]N!cEr;@-
for(int i=0;i<CountCache.list.size();i++){ Eqt>_n8
CountBean cb=(CountBean)CountCache.list.getFirst(); 3;EBKGg|
CountCache.list.removeFirst(); atfK?VK#
ps.setInt(1, cb.getCountId()); bY=Yb
ps.executeUpdate();⑴ +hMF\@
//ps.addBatch();⑵ ^|%7}=e
} Um
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//int [] counts = ps.executeBatch();⑶
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conn.commit(); hmtDw,j
}catch(Exception e){ H~ =;yy
e.printStackTrace(); f.U.(
} finally{ BlfW~l'mx
try{ 4yR X{Bl|
if(ps!=null) { g+u5u\k
ps.clearParameters(); ; HjT
ps.close(); ;+VHi%5Z
ps=null; lK y4Nry9
} =&;}#A%m
}catch(SQLException e){} ig:z[k?
DBUtils.closeConnection(conn); )yv~wi
} H?dEgubg7]
} P,SI0$Z
public long getLast(){ z%WOv~8~
return lastExecuteTime; )mRKIM}*W
} \!'K#%]9
public void run(){ hUMFfc?
long now = System.currentTimeMillis(); %'[ pucEF
if ((now - lastExecuteTime) > executeSep) { )N]%cO(^
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^NOy:>
//System.out.print(" now:"+now+"\n"); BjbpRQ,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 29h_oNO
lastExecuteTime=now; H6-{(:
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executeUpdate(); m_>~e}2'A
} <=!|U0YV
else{ ? 1b*9G%i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4 {3<
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} 9 kS;_(DB
} R{Qvpd$y
} I}7=\S/@
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 %Z6\W;
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类写好了,下面是在JSP中如下调用。 f%TP>)jag!
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<% X+k`UM~
CountBean cb=new CountBean(); G@]|/kN1y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); s$;IR
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CountCache.add(cb); g4>1> .s
out.print(CountCache.list.size()+"<br>"); i"C?6R
CountControl c=new CountControl(); 'QEQyJ0EB
c.run(); oq }Q2[.b
out.print(CountCache.list.size()+"<br>"); lIF*$#`oh*
%>