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: #:jHp44J
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CountBean.java 9 *xR6
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/* N1Ng^aY0
* CountData.java @>u}eB>Kn
* I?]ohG K
* Created on 2007年1月1日, 下午4:44 9eR-
* 7X`l&7IXP
* To change this template, choose Tools | Options and locate the template under RW|`nL
* the Source Creation and Management node. Right-click the template and choose XYjV.j\
* Open. You can then make changes to the template in the Source Editor. u&^b~#T
*/ jGJLSEe_
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package com.tot.count; j1^I+j)
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/** >i_2OV
* >/g#lS 5
* @author R(!s
*/ d.3E[AJa(
public class CountBean { j -0z5|*KE
private String countType; 81](T<
int countId; `
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/** Creates a new instance of CountData */ @>u]4Jn
public CountBean() {} hM@
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public void setCountType(String countTypes){ >x/z7v?^I
this.countType=countTypes; \O}E7-
} nv GF2(;l
public void setCountId(int countIds){ J
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this.countId=countIds; _?<|{O
} [6 pD
public String getCountType(){ Jy^u?
return countType; 1Y/s%L
} ?@BTGUK"C
public int getCountId(){ V\t.3vT
return countId; 0f~C#/[t7
} (g EBOol
} _+p4Wvu~0
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CountCache.java N|1M1EBOu>
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/* s2teym,uG
* CountCache.java 1jCLO}
* (XeE2l2M
* Created on 2007年1月1日, 下午5:01 PjZvQ\Z
* ,3?Q(=j
* To change this template, choose Tools | Options and locate the template under XnDUa3
* the Source Creation and Management node. Right-click the template and choose FR$:"
* Open. You can then make changes to the template in the Source Editor. ~s%
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*/ <L`KzaA
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package com.tot.count; D'7SAFOM
import java.util.*; {F3xJ[
/** y6LWx:
* LISM ngQ.
* @author M|6A0m#Q
*/ qo p^;~
public class CountCache { \wo?47+=
public static LinkedList list=new LinkedList(); `JOOnTenQ
/** Creates a new instance of CountCache */ 0C1pt5K
public CountCache() {} ^.KwcXr
public static void add(CountBean cb){ %{ABaeb]
if(cb!=null){ Q(lo{AFc
list.add(cb); L_vISy%\b
} p=;=w_^y
} [p{#XwN
} pv*,gSS
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CountControl.java hakKs.U|[
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/* wLmhy,
* CountThread.java 5i>$]*o
* 1xD=ffM>8N
* Created on 2007年1月1日, 下午4:57 t?q@H8
* 1KMLG=
* To change this template, choose Tools | Options and locate the template under V"*O=h
* the Source Creation and Management node. Right-click the template and choose BbW^Wxd3
* Open. You can then make changes to the template in the Source Editor. r
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*/ # ,7e
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package com.tot.count; eCN })An
import tot.db.DBUtils; bvS(@
import java.sql.*; <0H"|:W>I]
/** )>.&N[v
* n1~o1
* @author {XNREjhm
*/ CsTF
public class CountControl{ V=zi
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private static long lastExecuteTime=0;//上次更新时间 \Kl+ 5%L
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 L[^9E'L$
/** Creates a new instance of CountThread */ Z3{>yYR+
public CountControl() {} ~KW,kyXBnD
public synchronized void executeUpdate(){ zhpx"{_
Connection conn=null; 4kG,*3&2
PreparedStatement ps=null; qR(\5}
try{ My<snmr2d
conn = DBUtils.getConnection(); "SzdDY6
conn.setAutoCommit(false); 1abtgDL
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vg
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for(int i=0;i<CountCache.list.size();i++){ w9NHk~LHKF
CountBean cb=(CountBean)CountCache.list.getFirst(); KMU4n-s"o
CountCache.list.removeFirst(); eln&]d;
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ IqC]! H0
//ps.addBatch();⑵ D[^m{ 9_
} 0|$v-`P$
//int [] counts = ps.executeBatch();⑶ @c<3b2
conn.commit(); c/zJv*}x?
}catch(Exception e){ ANJ$'3tg
e.printStackTrace(); IkBei&4F`
} finally{ 30XR
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try{ %;e/7`>Ma
if(ps!=null) { c.,2GwW
ps.clearParameters(); I 4,K43|
ps.close(); ;cPy1
ps=null; P^w#S
} ;\lW5ZX
}catch(SQLException e){} 1jN-4&
DBUtils.closeConnection(conn); y>72{
} 3jlh}t>$l
} } w
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public long getLast(){ o3I Tr';
return lastExecuteTime; F{eU";D
} EX?MA6U
public void run(){ >p.O0G
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long now = System.currentTimeMillis(); blTo5NLX
if ((now - lastExecuteTime) > executeSep) { jFA{+Yr1
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5e$~)fL
//System.out.print(" now:"+now+"\n"); O
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?gJy3@D
lastExecuteTime=now; -PS#Z0>
executeUpdate(); <Wp
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} Hm$=h>rY9[
else{ `e(vH`VZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); iMs5zf<M
} =Qgt${|
} f.
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} \/1<E?Q
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 !<SA6m#
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类写好了,下面是在JSP中如下调用。 l2l(_$@3
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<% %*&UJpbA
CountBean cb=new CountBean(); sVJ!FC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q5FM8Q
CountCache.add(cb); {K9/HqH
out.print(CountCache.list.size()+"<br>"); ,4ei2`wV
CountControl c=new CountControl(); -u?S=h}
c.run(); /\H>y
out.print(CountCache.list.size()+"<br>"); w9o^s5n
%>