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?Y%y@.
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CountBean.java (DKpJCx
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/* Gh|1%g"gm
* CountData.java 7@tr^JykO
* ! 2Y,
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* Created on 2007年1月1日, 下午4:44 'A8T.BU
* ~?b(2gn
* To change this template, choose Tools | Options and locate the template under a/)TJv
* the Source Creation and Management node. Right-click the template and choose (%+DE4?
* Open. You can then make changes to the template in the Source Editor. F/EHU?_EI
*/ &<^@/osi
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package com.tot.count; XcfTE
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/** oHi&Z$#!n
* tfv]AC7x
* @author X?7$JV-:
*/ s:]rL&|
public class CountBean { #{
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private String countType; dqKTF_+VhA
int countId; Y?%6af+
/** Creates a new instance of CountData */ v@t*iDa?7
public CountBean() {} ":-)mfgGU
public void setCountType(String countTypes){ wH${q@z _
this.countType=countTypes; F~l3?3ZV
} IG9Q~7@
public void setCountId(int countIds){ |g'sRTKJ
this.countId=countIds; ryn)
} s`
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public String getCountType(){ x(=kh%\;
return countType; U.^)|IHW
} jZ{S{"j
public int getCountId(){ n3|~X/I
return countId; {YGz=5 ^
}
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} 2bxT%xH:g
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CountCache.java *UyV@
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/* +p cj8K%
* CountCache.java \
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* Y?5yzD:
* Created on 2007年1月1日, 下午5:01 Maa.>2v<
* NqwVsVL
* To change this template, choose Tools | Options and locate the template under VmUM_Q~
* the Source Creation and Management node. Right-click the template and choose "pWdz}!
* Open. You can then make changes to the template in the Source Editor. 5AjK7[<L
*/ OUdeQO?
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package com.tot.count; _+Q$h4t
import java.util.*; tAC,'im:*
/** W?l .QQk
* )-QNWN
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* @author ~lF lv+,%
*/ }agl:~C
public class CountCache { P5d@-l%}
public static LinkedList list=new LinkedList(); ~NcJLU!au
/** Creates a new instance of CountCache */ oOL3O@)w>
public CountCache() {} SQ
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public static void add(CountBean cb){ 2?r8>#_*
if(cb!=null){ GVfu_z?
list.add(cb); U.)G#B
} \Zh)oUHd
} EU@mrm?
} F889JSZ%
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CountControl.java dikWk
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/* ~r!5d@f.6
* CountThread.java j^ _I{
* :HE]P)wz-
* Created on 2007年1月1日, 下午4:57 #pe{:f?
* #w*pWD^
* To change this template, choose Tools | Options and locate the template under 9kF#*
* the Source Creation and Management node. Right-click the template and choose Ds
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*
* Open. You can then make changes to the template in the Source Editor. !U#++Zig%
*/ a`-hLX)~Z
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package com.tot.count; I1myu Z
import tot.db.DBUtils; +_gT|vlU
import java.sql.*; 6oP{P_Pxi
/** 87K)qsv8
* pq[mM!;#v
* @author UC1!J
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*/ reA8=>b/
public class CountControl{ t>wxK
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private static long lastExecuteTime=0;//上次更新时间 qp W#!Vbx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @:7gHRJ!
/** Creates a new instance of CountThread */ P*PL6UQ
public CountControl() {} VU/W~gb4"A
public synchronized void executeUpdate(){ y@M}T{,/
Connection conn=null; B\_u${C
PreparedStatement ps=null; 8`G{1lr4o
try{ x}.d`=
conn = DBUtils.getConnection(); ^-IsK#r.k
conn.setAutoCommit(false); "k-ov9yK
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mbBRuPEa=u
for(int i=0;i<CountCache.list.size();i++){ d# 3tQ*G/
CountBean cb=(CountBean)CountCache.list.getFirst(); S/-7Zo&w+
CountCache.list.removeFirst(); X[Ek'=}
ps.setInt(1, cb.getCountId()); ~RXpz-Ye
ps.executeUpdate();⑴ aEDN]O95?
//ps.addBatch();⑵ u-[t~-(a
} "rGOw'!q>
//int [] counts = ps.executeBatch();⑶ (L5'rNk
conn.commit(); `XxG"k\/S
}catch(Exception e){ I/Jp,~JT*
e.printStackTrace(); + |qfgi
} finally{ HqdJdWl#"
try{ jBv$^L
if(ps!=null) { *>'2$me=
ps.clearParameters(); JYd7@Msfc
ps.close(); atf%7}2
ps=null; ~u0xXfv#
} *e<Eu>fW#&
}catch(SQLException e){} #\;>8
DBUtils.closeConnection(conn); YvruK:I
} ch>Vv"G>
} hoR=%pC*
public long getLast(){ 5w3 ZUmjO
return lastExecuteTime; A*;?U2
} V-_/(xt*
public void run(){ +%wWSZ<#
long now = System.currentTimeMillis(); CofH}-
if ((now - lastExecuteTime) > executeSep) { g(<T u^F
//System.out.print("lastExecuteTime:"+lastExecuteTime); iS"8X#[]N
//System.out.print(" now:"+now+"\n"); h.V]f S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); d;~ 3P
lastExecuteTime=now; vWl[l
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executeUpdate(); G*\abL
} \E@s_fQ]
else{ RxZm/:yuJ.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |rFR8srPG
} w,Z"W;|
} #%^\\|'z
} e3eVvl5]
//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 ]jc_=I6)
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类写好了,下面是在JSP中如下调用。 |mxNUo-
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<% $_C+4[R?
CountBean cb=new CountBean(); b,s Gq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v**z$5x9
CountCache.add(cb); SY,I>-%
out.print(CountCache.list.size()+"<br>"); MBB5wj
CountControl c=new CountControl(); ?j/kOD0
c.run(); XDk'2ycv
out.print(CountCache.list.size()+"<br>"); Y{Da+
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