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: No>XRG+
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CountBean.java pYa8iQ`6U;
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/* 5,})x]'x
* CountData.java Fm_^7|
* u\ro9l
* Created on 2007年1月1日, 下午4:44 G|Rsj{2'
* 7"@^JxYN
* To change this template, choose Tools | Options and locate the template under ^[,Q2MHCT(
* the Source Creation and Management node. Right-click the template and choose g(B &A
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* Open. You can then make changes to the template in the Source Editor. KV9'ew+M
*/ X0Y1I}gD
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package com.tot.count; $wg5q\Rv
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/** d00#;R
* uf]SPG#/D
* @author <k!M+}a 9V
*/ #<s6L"Z-
public class CountBean { 2-728
private String countType; W@`2+}
int countId; {^=T&aCYdS
/** Creates a new instance of CountData */ "s]r"(MX
public CountBean() {} T\I}s"d
public void setCountType(String countTypes){ XLb
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this.countType=countTypes; g>-pC a
} 3O7]~5 j1
public void setCountId(int countIds){ pYf57u
this.countId=countIds; Q)c3=.[>
} 3u#bx1
public String getCountType(){ U$v|c%6
return countType; `-W.uOZ0
} SK
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public int getCountId(){ E-IV v
return countId; :+NZW9_
} S"'0lS
} @&?E3?5ll
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CountCache.java O 7RIcU
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/* h?R{5?RxK
* CountCache.java JJ_b{ao<
* G%^jgr)
* Created on 2007年1月1日, 下午5:01 *o.f<OwOz
* SQ8xfD*
* To change this template, choose Tools | Options and locate the template under \ne1Xu:hM
* the Source Creation and Management node. Right-click the template and choose d-c<dS+R
* Open. You can then make changes to the template in the Source Editor. /N= }wC
*/ ?C)a0>L
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package com.tot.count; B|pO2de
import java.util.*; 5;'(^z-bL
/** VzfaUAIZl
* 'L?e)u.
* @author 0t*e#,y
*/ \c}_!.xj"
public class CountCache { N8x[8Rp
public static LinkedList list=new LinkedList(); k%uR!cL
/** Creates a new instance of CountCache */ xfoQx_]$Im
public CountCache() {} p 4_j>JPv5
public static void add(CountBean cb){ ~MWI-oK
if(cb!=null){ g>G+?PY
list.add(cb); uN>JX/-
} oCfO:7
} GT.1,E,Vw
} 6&|hpp#[
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CountControl.java J,4,#2M8
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/* (xpt_]Q!H
* CountThread.java Hb}O/G$a*
* fF6bEJl3
* Created on 2007年1月1日, 下午4:57 /]j^a:#"6t
* ~,ZU+
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose r$[`A_
* Open. You can then make changes to the template in the Source Editor. e}dGK=`
*/ ,w`g+ 9v
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package com.tot.count; $7h]A$$Fv
import tot.db.DBUtils; !/nXEjW?
import java.sql.*; Q^\m@7O
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/** _%g L
* P:D;w2'Q
* @author aVB/CoM9
*/ $ UNC0(4
public class CountControl{ mtU{d^B
private static long lastExecuteTime=0;//上次更新时间 Q g~cYwX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |RjAp.pm
/** Creates a new instance of CountThread */ nQGl]2
public CountControl() {} ]K?;XA3 dZ
public synchronized void executeUpdate(){ c wNJ{S+
Connection conn=null; '9{`Czc(Gb
PreparedStatement ps=null; R2Es~T
try{ -pmb-#`M
conn = DBUtils.getConnection(); i<0_sxfUD
conn.setAutoCommit(false); m)7Ql!l
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); vB74r]'F
for(int i=0;i<CountCache.list.size();i++){ r>: ~!o*
CountBean cb=(CountBean)CountCache.list.getFirst(); y1{TVpN
CountCache.list.removeFirst(); P ~ :
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ps.setInt(1, cb.getCountId()); d1P|v(
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ps.executeUpdate();⑴ Qb%o%z?hee
//ps.addBatch();⑵ s\+|
ql
} mT:NC'b<9
//int [] counts = ps.executeBatch();⑶ vtq$@#?~ b
conn.commit(); xU/7}='T
}catch(Exception e){ |kY}G3/
e.printStackTrace(); M*!WXQlud
} finally{ 7|5X> yt
try{ Ii9[[I
if(ps!=null) { Ff{,zfN+3
ps.clearParameters(); BLN|QaZ
ps.close(); dGyrzuPJ
ps=null; D@2L<!\
} AH{#RD
}catch(SQLException e){} Um}f7^fp^l
DBUtils.closeConnection(conn); e Fh7#~m
} 6Hbu7r*tm
} g,9&@g/
public long getLast(){ 3v@h&7<E
return lastExecuteTime; }u9#S
} ?g\emhG
public void run(){ Nq9\ 2p
long now = System.currentTimeMillis(); m"@o
if ((now - lastExecuteTime) > executeSep) { nU4to
//System.out.print("lastExecuteTime:"+lastExecuteTime); h1t~hrq
//System.out.print(" now:"+now+"\n"); 3k3C\Cw
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6r|=^3{
lastExecuteTime=now; W#)X@TlE
executeUpdate(); lD^c_b
} G9^xv
else{ +4$][3.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 6hMKAk
} #f [}a
} t"zi'9$t
} Lqdapx"Z_
//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 }DQTy.d;P
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类写好了,下面是在JSP中如下调用。 U9ZuD40\
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<% tr5j<O
CountBean cb=new CountBean(); SRtw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Jz}`-fU`
CountCache.add(cb); VKkvf"X
out.print(CountCache.list.size()+"<br>"); c]h@<wnv
CountControl c=new CountControl(); 0SfW:3
c.run(); B0U(B\~Y
out.print(CountCache.list.size()+"<br>"); Bn9#F#F<
%>