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: 0"OEOYs}
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CountBean.java .|[{$&B
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/* O^~IY/[
* CountData.java 9$HKP9G
* ?3BcjD0
* Created on 2007年1月1日, 下午4:44 8<Iq)A]'Z
* ASbIc"S6
* To change this template, choose Tools | Options and locate the template under 6a,8t
* the Source Creation and Management node. Right-click the template and choose sr;&/l#7h
* Open. You can then make changes to the template in the Source Editor. -yqgs>R(d
*/ vGv<WEE
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package com.tot.count; O +o)z6(
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/** BZW03e8|
* N[W#wYbH
* @author GL O3v.
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*/ iUcX\
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public class CountBean { Vpg>K #w
private String countType; &233QRYM
int countId; Am*IC?@tq
/** Creates a new instance of CountData */ vcu@_N 1Dc
public CountBean() {} bSw^a{~)
public void setCountType(String countTypes){ p48enH8CO
this.countType=countTypes; X\;:aRDS
} rn)Gx25
public void setCountId(int countIds){ e7GYz7
this.countId=countIds; P{A})t7
} oH=?1~e
public String getCountType(){ >Gpq{Ph[
return countType; m)L50ot:/
} C1NU6iV^z
public int getCountId(){ E:8*o7
return countId; ;'{7wr|9
} ljK?2z>
} mce qZv
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CountCache.java wIi(\]Q
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/* /o4e
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* CountCache.java B<EqzP*#
* SN@>m pcJS
* Created on 2007年1月1日, 下午5:01 m"~ddqSMT
* ]|!|3lQ
* To change this template, choose Tools | Options and locate the template under YtvDayR>
* 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. i
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*/ V$hL\`e
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package com.tot.count; wY ItG"+6
import java.util.*; `l]Lvk8O
/** !Np7mv\7
* yQ/O[(
* @author \r:*`Z*y
*/ &UH0Tw4
public class CountCache { !T<,fR+8X
public static LinkedList list=new LinkedList(); k9*UBx
/** Creates a new instance of CountCache */ UY9*)pEE
public CountCache() {} *~P| ? D'
public static void add(CountBean cb){ ?S&
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if(cb!=null){ yn!;Z._
list.add(cb); #EUT"^:d
} h^rG5Q
} yL
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} v CsE|eMP
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CountControl.java 0B8Wf/j?M
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/* AQ$)JPs
* CountThread.java T+T)~!{%
* fLs>|Rh
* Created on 2007年1月1日, 下午4:57 %iNgHoH
* cr -5t4<jK
* To change this template, choose Tools | Options and locate the template under B ZU@W%E
* 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. yg8= G vO
*/ l4T[x|')M
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package com.tot.count; 5yt= ~
import tot.db.DBUtils; &i3SB[|
import java.sql.*; H2|'JA#v
/** O9N!SQs80
* b0'}BMJ
* @author
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*/ H HX q_-V
public class CountControl{ <;#gcF[7>
private static long lastExecuteTime=0;//上次更新时间 MzB.Vvsy%9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g4q{
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/** Creates a new instance of CountThread */ +a,#BSt
public CountControl() {} Q[3hOFCX
public synchronized void executeUpdate(){ Z0H_l/g
Connection conn=null; J#H,QYnf(L
PreparedStatement ps=null; PdVY tK%
try{ 6?5dGYAX<
conn = DBUtils.getConnection(); ~rI2 RJ
conn.setAutoCommit(false); HABUf^~-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); D"$ 97
for(int i=0;i<CountCache.list.size();i++){ 2?LPr
CountBean cb=(CountBean)CountCache.list.getFirst(); %x,HQNRDU
CountCache.list.removeFirst(); lE%KzX?&
ps.setInt(1, cb.getCountId()); S=S/]]e
ps.executeUpdate();⑴ ye(av&Hn
//ps.addBatch();⑵ ;=@O.iF;H
} 2sgp$r
//int [] counts = ps.executeBatch();⑶ a{e
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conn.commit(); "D>/#cY1/
}catch(Exception e){ ?{ \7th37
e.printStackTrace(); x(Uv>k~i}
} finally{ j0oto6z~b
try{ -]}#Z:&
if(ps!=null) {
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ps.clearParameters(); #F3'<(j
ps.close(); L;g2ZoqIr0
ps=null; 6yUThv.G#
} $<=d[6
}catch(SQLException e){} R-W.$-rF
DBUtils.closeConnection(conn); sRBfLN2C
} ?Qd`Vlp7
} [oBRH]9cq
public long getLast(){ 6NyUGGRq
return lastExecuteTime; v; ewMiK@E
} <2kv/
public void run(){ {=Ji2k0U'
long now = System.currentTimeMillis(); fUis_?!
if ((now - lastExecuteTime) > executeSep) { F@ pf._c
//System.out.print("lastExecuteTime:"+lastExecuteTime); FeZW S>N
//System.out.print(" now:"+now+"\n"); .L^j:2(L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]!1HN3
lastExecuteTime=now; ~#so4<A`3
executeUpdate(); Q$:,N=%
} KCbOO8cQS
else{ i&m6;>?`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >(YH@Z&;
} h)W#
} l| \ -d
} |FaK=e
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 X-bM`7'H
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类写好了,下面是在JSP中如下调用。 :.BjJ2[S
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<% Zn*W2s^^{
CountBean cb=new CountBean(); ~z41$~/
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :KRNLhWb
CountCache.add(cb); %0vsm+XQ0E
out.print(CountCache.list.size()+"<br>"); DBu8}2R
CountControl c=new CountControl(); v13\y^t
c.run(); Xfb-<
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out.print(CountCache.list.size()+"<br>"); Wy1.nn[
%>