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: B$DZ]/<
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CountBean.java 4zX=3iBt
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/* y*(_\\
* CountData.java wEK%T P4
* _]EyEa
* Created on 2007年1月1日, 下午4:44 )DRkS,I
* DOT=U
_
* To change this template, choose Tools | Options and locate the template under qhN[Dj(d
* the Source Creation and Management node. Right-click the template and choose $*i7?S@~-
* Open. You can then make changes to the template in the Source Editor. (qj,GmcS
*/ 9c6 '
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package com.tot.count; 5Fr;
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/** m1i4 ,
* hLSTSD}
* @author kLq(!Gs
*/ |""=)-5N
public class CountBean { E0T&GR@.
private String countType; 8T<@ @6`T
int countId; {GK(fBE
/** Creates a new instance of CountData */ n{L:MT9TD
public CountBean() {} OH0S2?,{>
public void setCountType(String countTypes){ 7}A5u,.,ht
this.countType=countTypes; AzxL%,_
} b h*^{
public void setCountId(int countIds){ U @)k3^
this.countId=countIds; RA}U#D:$i
} 8s~\iuk
public String getCountType(){ .<HC[ls
return countType; %N>\:85?
} +8^5C,V
public int getCountId(){ 5St`@
return countId; i,([YsRuou
} eQ$e*|}"m
} 3;y_qwA
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CountCache.java |.Em_*VG
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/* abL/Y23
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* CountCache.java FOc|*>aKP
* G
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* Created on 2007年1月1日, 下午5:01 TNJ<!6
* uC- A43utv
* To change this template, choose Tools | Options and locate the template under wL Y#dm
* the Source Creation and Management node. Right-click the template and choose %
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* Open. You can then make changes to the template in the Source Editor. ^Wif!u/HM
*/ VccM=w%*
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package com.tot.count; &{ DR6
import java.util.*; 1;aF5~&
/** ;i.I&*t
* ~:T3|
* @author r }ZLf
*/ c6t2Q6zV
public class CountCache { >6OCKl
public static LinkedList list=new LinkedList(); MF&3e#mdB
/** Creates a new instance of CountCache */ >_-!zjO8u
public CountCache() {} |3S'8OeCI
public static void add(CountBean cb){ NvUu.
if(cb!=null){ ,GP!fsK
list.add(cb); :
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} &S<?07Z
} x)j/
} SOhSg]g
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CountControl.java LE8K)i
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/* S|~i>
* CountThread.java yQ8M >H#J
* /X@7ju;
* Created on 2007年1月1日, 下午4:57 :-w@^mli
* aF,jJ}On
* To change this template, choose Tools | Options and locate the template under 4g>1Gqv6
* the Source Creation and Management node. Right-click the template and choose jo<>Hc{g>
* Open. You can then make changes to the template in the Source Editor. ;0;3BH A
*/ f9vcf# 2
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package com.tot.count; {EOn r1
import tot.db.DBUtils; C5>{Q:.`e'
import java.sql.*; j \!~9
/** Y_$^:LG
* -Uzc"Lx B
* @author M`)s>jp@w
*/ >sn"
public class CountControl{ 4xv9a;fP
private static long lastExecuteTime=0;//上次更新时间 ?F)_T
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |~ z8<
/** Creates a new instance of CountThread */ +xn&K"]:3
public CountControl() {} chKF6n
public synchronized void executeUpdate(){ uFGv%W
Connection conn=null; W"W@WG9X0
PreparedStatement ps=null; BO8%:/37[4
try{ cC b>zI
conn = DBUtils.getConnection(); ;>inT7?3|
conn.setAutoCommit(false); w/qQ(]n8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); uG2Xkj
for(int i=0;i<CountCache.list.size();i++){ ARmu{cL
CountBean cb=(CountBean)CountCache.list.getFirst(); BXT80a\
CountCache.list.removeFirst(); 2~#ZO?jE6
ps.setInt(1, cb.getCountId()); ]&&I|K_
ps.executeUpdate();⑴ 8o!
//ps.addBatch();⑵ (hpTJsZ
} :[A?A4l
//int [] counts = ps.executeBatch();⑶ |}M~kJ)
conn.commit(); JCM)N8~i
}catch(Exception e){ WA<H
e.printStackTrace(); mw:3q6
} finally{ )W[KD,0+j
try{ E^oEG4X@
if(ps!=null) { <FXQxM5"
ps.clearParameters();
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ps.close(); 6>@(/mh*
ps=null; }9MW!Ss
} bk/.<Rt
}catch(SQLException e){} +<'uw
DBUtils.closeConnection(conn); NFdJb\
} w;lx:j!Vp$
} O4lxeiRgC
public long getLast(){ )fxo)GS
return lastExecuteTime; 1i5 vW- '4
} &Tf=~6
public void run(){ tfi2y]{A
long now = System.currentTimeMillis(); fGu5%T,
if ((now - lastExecuteTime) > executeSep) { 38"8,k
//System.out.print("lastExecuteTime:"+lastExecuteTime); /uy&2l
//System.out.print(" now:"+now+"\n"); @#bBs9@gv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [37f#p
lastExecuteTime=now; VaD:
executeUpdate(); OwNA N
} L~^e\^sP
else{ 1.hOE>A%
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +9<,3IJe6
} .a 'ETNY:>
} _DNkdS
[[
} `l
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//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 ;s}-X_O<
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类写好了,下面是在JSP中如下调用。 >xxXPvM<`
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<% yC9:sQ'k
CountBean cb=new CountBean(); / e~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t:?<0yfp&
CountCache.add(cb); B|$\/xO
out.print(CountCache.list.size()+"<br>"); H @3$1h&YS
CountControl c=new CountControl(); !1ie:z>s
c.run(); 5pNvzw
out.print(CountCache.list.size()+"<br>"); OGSEvfW
%>