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: I Y2)?"A
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CountBean.java M*z~gOZ
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/* d\p,2
* CountData.java ;gBRCZ
* 0*rQ3Z
* Created on 2007年1月1日, 下午4:44 "l*Pd$sr
* fF?z|
* To change this template, choose Tools | Options and locate the template under N"8_S0=pw
* the Source Creation and Management node. Right-click the template and choose #.it]Nv{
* Open. You can then make changes to the template in the Source Editor. ABF"~=aL
*/ ko Z
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package com.tot.count; =; ^%(%Y{m
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/** T.@aep\"
* WX=Jl<
* @author &=#[(vl
*/ >_o}
public class CountBean { &QDW9
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private String countType; U'8bdsF_
int countId; 'SCidN(n
/** Creates a new instance of CountData */ ~Q?a|mV,
public CountBean() {} WOQP$D9
public void setCountType(String countTypes){ Pf|siC^;s~
this.countType=countTypes; QrfG^GID
} 'qjeXqGH$
public void setCountId(int countIds){ p89wNSMl[
this.countId=countIds; m1),;RsH
} $UgA0]qn
public String getCountType(){ R#2 t)y
return countType; MOsl_^c
} [21=5S
public int getCountId(){ 3|1ilP
return countId; w9NHk~LHKF
} ux_Mrh'
} ?**+e%$$
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CountCache.java 7]9
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/* IqC]! H0
* CountCache.java 0}$Hi
* b+@JY2dvj
* Created on 2007年1月1日, 下午5:01 '@p['#\uI
* (@t(?Js
* To change this template, choose Tools | Options and locate the template under o>/YAX:.!T
* the Source Creation and Management node. Right-click the template and choose /wP@2ADB
* Open. You can then make changes to the template in the Source Editor. L%Ow#.[C2
*/ W.dt:_
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package com.tot.count; sA'6ty
import java.util.*; --HF8_8;'
/** %1O;fQL
* p$h4u_
* @author c}y [[EX
*/ !X"K=zt"
public class CountCache { <(-3_s6-
public static LinkedList list=new LinkedList(); $4tWI O
/** Creates a new instance of CountCache */ !|O~$2O@
public CountCache() {} U7oo$gW%|T
public static void add(CountBean cb){ "Jt.lL ]5
if(cb!=null){ r.#t63Rb
list.add(cb); f2^r[kPX"
} wtc!>
} e
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} v=_6XF
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CountControl.java bty/
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/* #;%JT
* CountThread.java kMtwiB|7j
* x9;gT&@H
* Created on 2007年1月1日, 下午4:57 EGZb7:Y?
* 'h^0HE\~p
* To change this template, choose Tools | Options and locate the template under `FYv3w2
* the Source Creation and Management node. Right-click the template and choose XVKfl3'%
* Open. You can then make changes to the template in the Source Editor. 5]HS^II"
*/ tZ^Ou89:rG
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package com.tot.count; 87=^J
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import tot.db.DBUtils; bzX\IrJpOZ
import java.sql.*; GlbySD@
/** dHK`eS$sb
* SzUpWy&
* @author oo=Qt(#
*/ hjIT_{mk
public class CountControl{ i?fOK_d
private static long lastExecuteTime=0;//上次更新时间 G8r``{C!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Hm$=h>rY9[
/** Creates a new instance of CountThread */ =,Dqqf
public CountControl() {} WAn~+=Ax
public synchronized void executeUpdate(){ 'Y56+P\u
Connection conn=null; q|Q k2M
PreparedStatement ps=null; qe!fk?T}
try{ jBU4F~1y
conn = DBUtils.getConnection(); P@,nA41,j
conn.setAutoCommit(false); KuMF^0V%c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); |1b_3?e
for(int i=0;i<CountCache.list.size();i++){ &|!7Z4N
CountBean cb=(CountBean)CountCache.list.getFirst(); T}"6wywM
CountCache.list.removeFirst(); 'ow.=1N-
ps.setInt(1, cb.getCountId()); Yc,7tUz#
ps.executeUpdate();⑴ Y7vA`kjD-C
//ps.addBatch();⑵ Sh?4ri@:
} Sqo
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//int [] counts = ps.executeBatch();⑶ Y=?yhAw
conn.commit(); hi0R.V&
}catch(Exception e){ L+CyQq
e.printStackTrace(); rMU T_^
} finally{ xfb]b2
try{ L2, 1Kt7
if(ps!=null) { z.Y$7bf)
ps.clearParameters(); d)pV;6%[$q
ps.close(); Hd,p!_
ps=null; !zPa_`P
} Db6om7N
}catch(SQLException e){} |\U5),m
DBUtils.closeConnection(conn); W2z*91$
} Sp}tD<V
}
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public long getLast(){ zOGU8Wg
return lastExecuteTime; (iRide
} I =1+h
public void run(){ l'\pk<V
long now = System.currentTimeMillis(); :dLAs@z
if ((now - lastExecuteTime) > executeSep) { PSPmO'C+
//System.out.print("lastExecuteTime:"+lastExecuteTime); wlEdt1G
//System.out.print(" now:"+now+"\n"); * 1Od-3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); uPRQU+
lastExecuteTime=now; i:u1s"3~
executeUpdate(); Rr!Y3)f;
} 7^Ns&Q
else{ v{9t]s>B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X`fn8~5
} vq!_^F<
} 7f~Sf
} _L@2_#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 *P#WDXRwd
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类写好了,下面是在JSP中如下调用。 Q4*fc^?u
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<% ,:`ND28V7
CountBean cb=new CountBean(); JB>b`W9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); A0fFv+RN3
CountCache.add(cb); (sQr X{~
out.print(CountCache.list.size()+"<br>"); bk)g;+@
CountControl c=new CountControl(); 'sxNDnGg
c.run(); {'AWZ(
out.print(CountCache.list.size()+"<br>"); ;q:jl~
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