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: z'?SRK5+
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CountBean.java Pa3{Ds
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/* B^H4Q
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* CountData.java ejP,29
* 52da]BW<
* Created on 2007年1月1日, 下午4:44 ,<7"K&
* [SK2 x4
* To change this template, choose Tools | Options and locate the template under ] gH
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* the Source Creation and Management node. Right-click the template and choose TViBCed40
* Open. You can then make changes to the template in the Source Editor. {F<)z%^
*/ )>ug{M%g
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package com.tot.count; tX@0:RX%
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/** Tw2Xe S
* 0Ulxp
* @author 5P-K *C&
*/ $Vo/CZW7
public class CountBean { 8FAT(f//.
private String countType; ^!q 08`0
int countId; eVJ= .?r
/** Creates a new instance of CountData */ NKRaQr
public CountBean() {} X'YfjbGo
public void setCountType(String countTypes){ qsD?dHi7
this.countType=countTypes; !>CE(;E>z
} V+Y|4Y&
public void setCountId(int countIds){ R
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this.countId=countIds; XPar_8I
} d^ 2u}^kG
public String getCountType(){ s>LA3kT
return countType; uCY(:;[<
} F~tm`n8Z
public int getCountId(){ @~JB\j9
return countId; P]|J?$1K
} oxUE79
} &r&;<Q
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CountCache.java ,h3269$J
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/* ?R dmKA
* CountCache.java Mi;}.K0J
* =6.8bZT\
* Created on 2007年1月1日, 下午5:01 qlz( W
* 83mlZ1jQz
* To change this template, choose Tools | Options and locate the template under NYWG#4D
* the Source Creation and Management node. Right-click the template and choose kA?X^nj@
* Open. You can then make changes to the template in the Source Editor. Ll008.#
*/ r~8D\_=s
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package com.tot.count; 5x:Ift
*
import java.util.*; p>2||
/** j)g_*\tQ
* i58ZV`Rk`
* @author 5W*7qD[m
*/ O<}ep)mr
public class CountCache { }wvwZ`5t
public static LinkedList list=new LinkedList(); &{X{36
/** Creates a new instance of CountCache */ b=6MFPbg
public CountCache() {} SZCF3m&pz
public static void add(CountBean cb){ aO~si=
if(cb!=null){ L~@ma(TV{K
list.add(cb); clh3
} E"Ya-8d=
} kWzuz#
} jlYD~)
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CountControl.java X=rc3~}f
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/* `,F&y{A
* CountThread.java u5xU)l3
* =gxgS<bde
* Created on 2007年1月1日, 下午4:57 y#hga5
* <_##YSGh,
* To change this template, choose Tools | Options and locate the template under }"F
?H:\
* the Source Creation and Management node. Right-click the template and choose 4yA9Ni
* Open. You can then make changes to the template in the Source Editor. ?b!CV
*/ tebWj>+1c
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package com.tot.count; g*:ae;GP
import tot.db.DBUtils; (|yRo
import java.sql.*; YD/B')/ s
/** }*fW!(*
* += |hMQ;
* @author 71oFm1m{
*/ -X"5G
public class CountControl{ tYI]LL
private static long lastExecuteTime=0;//上次更新时间 V_)5Af3wY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ^CowJ(y(
/** Creates a new instance of CountThread */ k #1`
public CountControl() {} Jngll
public synchronized void executeUpdate(){ -/(DPx
Connection conn=null; !Iw{Y'
PreparedStatement ps=null; {]t\`fjrg
try{ LK'S)Jk
conn = DBUtils.getConnection(); ltCwns
conn.setAutoCommit(false); *G%1_
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !ol hZ
for(int i=0;i<CountCache.list.size();i++){ 4A\BGD*5
CountBean cb=(CountBean)CountCache.list.getFirst(); U^E
CountCache.list.removeFirst(); p9FA_(`^
ps.setInt(1, cb.getCountId()); uE,i-g0$Id
ps.executeUpdate();⑴ blKDQ~T2
//ps.addBatch();⑵ N0y;PVAGu
} J6@(X8w{j
//int [] counts = ps.executeBatch();⑶ ^4xlZouCb
conn.commit(); &&(4n?
}catch(Exception e){ uR06&SaA>
e.printStackTrace(); )@8'k]Glw.
} finally{ }<(
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try{ q7 %=`l
if(ps!=null) { b>hBct}
ps.clearParameters(); i Q]T+}nn_
ps.close(); <Um1h:^
ps=null; fP^W"y
} 2ru*#Z#(
}catch(SQLException e){} aGq_hP
DBUtils.closeConnection(conn); B)j`}7O06
} +z]:CF
} aJuj7y-
public long getLast(){ <3SFP3^:
return lastExecuteTime; 2 pM
} kcq9p2zKv
public void run(){ >:Rt>po8|w
long now = System.currentTimeMillis(); z")3_5Br
if ((now - lastExecuteTime) > executeSep) { p0}+071o%
//System.out.print("lastExecuteTime:"+lastExecuteTime); >cwJl@wx-
//System.out.print(" now:"+now+"\n"); <r_P?
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >5Q^9 9V
lastExecuteTime=now; (uuEjM$3%
executeUpdate(); Pi&fwGL
} B|]t\(~$[
else{ ,(@Y%UW:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Dg9--wI}I9
} ;Zx K3/(7
} rQd1Ch
} boC>N
//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 h3UZ|B0=
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类写好了,下面是在JSP中如下调用。 x[GFX8h(k6
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<% hQg,#r(JE4
CountBean cb=new CountBean(); C&gOA8nf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); eeI9[lTw
CountCache.add(cb); /I`cS%U
out.print(CountCache.list.size()+"<br>"); O Ey:#9<'
CountControl c=new CountControl(); "xvV'&lQ
c.run(); sUyCAKebRr
out.print(CountCache.list.size()+"<br>");
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%>