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: onl,R{,`0
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CountBean.java q4Mv2SPT
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/* O=oIkvg
* CountData.java 3~?m?vj|Y
* z
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* Created on 2007年1月1日, 下午4:44 "O~kIT?/v
* xqfIm%9i}
* To change this template, choose Tools | Options and locate the template under #I\" 'n5M
* the Source Creation and Management node. Right-click the template and choose 6zI}?KZf
* Open. You can then make changes to the template in the Source Editor. vsJDVJ +=
*/ )r?-_qj=
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package com.tot.count; @@ cc/S
] !n3j=*
/** vU$n*M1`$
* Dt(xj}[tC
* @author g.\%jDM
*/ -b|"%e<'
public class CountBean { dWdD^>8Ef
private String countType; D@kf^1G
int countId; 3,n" d-
/** Creates a new instance of CountData */ d.HcO^
public CountBean() {} <v=s:^;C0
public void setCountType(String countTypes){ j4u
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this.countType=countTypes; =.w~qL
} 'V&Tlw|
public void setCountId(int countIds){ GWv i
this.countId=countIds; u60RuP&
} ("{"8
public String getCountType(){ a ,"
return countType; VfUHqdg-
} t7Mq>rFB
public int getCountId(){ F)v
return countId; <@Vf:`a!P>
} x2'pl
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} *eX/ZCn
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CountCache.java M8/:PmR<
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/* \+=`o .2
* CountCache.java i<):%[Q)>
* *+nw%gZG
* Created on 2007年1月1日, 下午5:01 qDU4W7|T`
* 64]8ykRD-
* To change this template, choose Tools | Options and locate the template under Y B,c=Wx
* the Source Creation and Management node. Right-click the template and choose ^bP`Iv
* Open. You can then make changes to the template in the Source Editor. [ D.%v~j
*/ H:XPl$;
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package com.tot.count; ~X3x-nAt
import java.util.*; v5@M 34
/** ;FW <%
* -*i_8`
* @author oOC&w0
*/ .FC+
public class CountCache { 3zu6#3^
public static LinkedList list=new LinkedList(); EW1,&H
/** Creates a new instance of CountCache */ +I3O/=)
public CountCache() {} /|<SD.:
public static void add(CountBean cb){ >]_^iD]*t
if(cb!=null){ LAH">E
list.add(cb); 841 y"@*BY
} AI Kz]J0;
} %ek0NBE7
} zBu@a:E%H
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CountControl.java <oV[[wl
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/* Z) 2d4:uv
* CountThread.java vSC1n8 /
* `GdH ,:S>
* Created on 2007年1月1日, 下午4:57 /t`\b
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* Z"%.
* To change this template, choose Tools | Options and locate the template under 4(LLRzzW
* the Source Creation and Management node. Right-click the template and choose 6h2keyod
* Open. You can then make changes to the template in the Source Editor. J"LLj*,0"
*/ 0<a|=kZ
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package com.tot.count; W/hzo*o'g
import tot.db.DBUtils; u~ipB*Zf
import java.sql.*; "YY<T&n
/** =CJ`0yDQ>
* jH!;}q
* @author f?
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*/ #qYgQ<TM!
public class CountControl{ #dL,d6a
private static long lastExecuteTime=0;//上次更新时间 B=L!WGl<!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $qz{L~ <
/** Creates a new instance of CountThread */ cWZITT{A
public CountControl() {} nJ]7vj,rB
public synchronized void executeUpdate(){ |1(x2x%}D^
Connection conn=null; *X/Vt$P
PreparedStatement ps=null; gBv!E9~l
try{ q+9->D(6
conn = DBUtils.getConnection(); _ia&|#n
conn.setAutoCommit(false); i .uyfV&F
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qnboXGaFu
for(int i=0;i<CountCache.list.size();i++){ zKGZg>q
CountBean cb=(CountBean)CountCache.list.getFirst(); ''@Tke3IG6
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); Mf#@8"l
ps.executeUpdate();⑴ $q:l \
//ps.addBatch();⑵ *3`R W<Z
} H'zAMGZa
//int [] counts = ps.executeBatch();⑶ #p>&|I
conn.commit(); K~,!IU_QG
}catch(Exception e){ J<"K`|F
e.printStackTrace(); SyVXXk 0
} finally{ #%@bZ f
try{ ?.Vuet
if(ps!=null) { Lw,}wM5X
ps.clearParameters(); {l,&F+W$C
ps.close(); Y4 z
ps=null; PiM(QR
} i@nRZ$ K
}catch(SQLException e){} iKE&yO3
DBUtils.closeConnection(conn); Awxm[:r>^
} -Yse^(^"s
} t2)uJN`a$X
public long getLast(){ nUpj+F#
return lastExecuteTime; Rf8Obk<
} `WOoC
public void run(){ ftTD-d
long now = System.currentTimeMillis(); jn|NrvrX
if ((now - lastExecuteTime) > executeSep) { GqL&hbpi
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5@%Gq)z5
//System.out.print(" now:"+now+"\n"); \ YF@r7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); n'^`;-
lastExecuteTime=now; ,.p
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executeUpdate(); pJ}U'*Z2
} yZ,pH1
else{ STjb2t,a
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^6kl4:{idE
} ]sb?lAxh{
} .:}<4;Qz94
} 7V::P_aUY
//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 gU+yqT7=
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类写好了,下面是在JSP中如下调用。 sx=1pnP9`
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<% BedL `[,
CountBean cb=new CountBean(); W vB]Rs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,= ApnNUgX
CountCache.add(cb); 1gK^x^l*f
out.print(CountCache.list.size()+"<br>"); %/w-.?bX
CountControl c=new CountControl(); A"M;kzAfHM
c.run(); \A\
out.print(CountCache.list.size()+"<br>"); 5l8F.LtO\
%>