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: uiR8,H9*M
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CountBean.java t&e{_|i#+
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/* <bEbweQrgm
* CountData.java m
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* k!'a,R:
* Created on 2007年1月1日, 下午4:44 ,/|T-Ka
* m#\dSl}
* To change this template, choose Tools | Options and locate the template under QD]6C2j*
* the Source Creation and Management node. Right-click the template and choose ]Gq !`O1
* Open. You can then make changes to the template in the Source Editor. ml
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*/ A_q3KB!$=+
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package com.tot.count; ((M>s&\y*Y
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/** d<P\&!R(
* hv>\gBe i
* @author _u QOHwn
*/ 8&b,qQ~
public class CountBean { C,|,-CY
private String countType; %| Lfuz*
int countId; Z=vU}S>r|v
/** Creates a new instance of CountData */ OYn}5RN
public CountBean() {} IyG}H}
public void setCountType(String countTypes){ yEE*B:
this.countType=countTypes; Zp=U
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} J<jy2@"tXo
public void setCountId(int countIds){ M[,@{u/
this.countId=countIds; g{&ui.ml&
} ^.QzQ1=D
public String getCountType(){ D2~*&'4y
return countType; XVZ
} amY!qg0P*
public int getCountId(){ {&1/V
return countId; f9{Rb/l!BQ
} [Y|t]^M
} Z4
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CountCache.java 2`=7_v
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/* ^s"R$?;h
* CountCache.java dDLeSz$b
* I51@QJX
* Created on 2007年1月1日, 下午5:01 {F.[&/A
* nZYBE030
* To change this template, choose Tools | Options and locate the template under E$p+}sP(C
* the Source Creation and Management node. Right-click the template and choose sLxc(d'A
* Open. You can then make changes to the template in the Source Editor. &0JI!bR(
*/ n/mG|)Xt
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package com.tot.count; HLG"a3tt
import java.util.*; `3&v6
/** r mg}N
* 7J<5f)
* @author QhJiB%M
*/ 8v%o,"
public class CountCache { Wvf
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public static LinkedList list=new LinkedList(); c\AfaK^KF
/** Creates a new instance of CountCache */ ;u)I\3`*!
public CountCache() {} 1yu4emye4
public static void add(CountBean cb){ [` 7ThHX
if(cb!=null){ mc\"yC^s
list.add(cb); B^^#D0<
} }-=|^
} Uz]|N6`
} YNi.SXH
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CountControl.java }&D32\
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/* +52{-a,>
* CountThread.java -nV9:opD
* {_v#~595
* Created on 2007年1月1日, 下午4:57 *0=j?~&
* *J`O"a
* To change this template, choose Tools | Options and locate the template under ZPYS$Ydy
* the Source Creation and Management node. Right-click the template and choose 9x=Y^',5
* Open. You can then make changes to the template in the Source Editor. 6T`i/".
*/ bOY |H~
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package com.tot.count; i=2N;sAl
import tot.db.DBUtils; P5ywhw-
import java.sql.*; 3(80:@|
/** b d!Y\OD
* },-H"Qs
* @author Pe3o;mx
*/ }@d @3
public class CountControl{ hp|YE'uYT
private static long lastExecuteTime=0;//上次更新时间 2<}%kQ`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 L~N460
/** Creates a new instance of CountThread */ h<<v^+m
public CountControl() {} IW] rb/H
public synchronized void executeUpdate(){ aK^q_ghh[
Connection conn=null; "3Y0`&:D
PreparedStatement ps=null; ey$&;1x#5
try{ ab?aQ*$+
conn = DBUtils.getConnection(); ]:J$w]\
conn.setAutoCommit(false); }Jj}%XxKs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); nAlQ7'
for(int i=0;i<CountCache.list.size();i++){ +mT_QsLEv
CountBean cb=(CountBean)CountCache.list.getFirst(); |+D!=
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CountCache.list.removeFirst(); KoT%Mfu
ps.setInt(1, cb.getCountId()); FfT`;j
ps.executeUpdate();⑴ .8JTe0
//ps.addBatch();⑵ 88$8d>-
} 5\VWC I
//int [] counts = ps.executeBatch();⑶ c@L< Z` u
conn.commit(); ~((O8@}J
}catch(Exception e){ F*ylnB3z
e.printStackTrace(); sK?twg;D*|
} finally{ l+0oS'`V*L
try{ BnF^u5kv %
if(ps!=null) { ,Ma^ &ypH
ps.clearParameters(); j^RmrOg,
ps.close(); NC6&x=!3
ps=null; H3-hcx54T
} e~"U @8xk~
}catch(SQLException e){} a/xn'"eli
DBUtils.closeConnection(conn); 19%imf
} @-`*m+$U6
} 3F^Q51:t
public long getLast(){ SNk=b6`9
return lastExecuteTime; ysnx3(+|
} U-k`s[dv
public void run(){ Dk5 1z@
long now = System.currentTimeMillis(); 'i|YlMFI g
if ((now - lastExecuteTime) > executeSep) { <t!W5q
//System.out.print("lastExecuteTime:"+lastExecuteTime); nKj7.,>;:<
//System.out.print(" now:"+now+"\n"); Q^^niVz
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); tw)mepwB
lastExecuteTime=now; ^E>3|du]O
executeUpdate(); ~WF\
} 5~DJWi,
else{ Xne1gms
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); dft!lBN
} 4 s9LB
} 9QJyZ
} 4Ftu
//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 C~exi[3
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类写好了,下面是在JSP中如下调用。 AbW6x
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<% #}5uno
CountBean cb=new CountBean(); FW DNpr
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }"%N4(Kd
CountCache.add(cb); M&M6;Ph
out.print(CountCache.list.size()+"<br>"); _
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CountControl c=new CountControl(); |CbikE}kL
c.run(); @BMx!r5kn
out.print(CountCache.list.size()+"<br>"); lq7E4r
%>