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: ~hxeD" w
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CountBean.java LR
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/* s>[vT?
* CountData.java P}w^9=;S
* $Qx(aWE0
* Created on 2007年1月1日, 下午4:44 M%nZu{
* V}3~7(
* To change this template, choose Tools | Options and locate the template under 6%Cna0x:&
* the Source Creation and Management node. Right-click the template and choose b}"vIRz
* Open. You can then make changes to the template in the Source Editor. 6
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*/ Y9lbf_51
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package com.tot.count; ;h*"E(Pp
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/** d#M?lS>
* gu~-}
* @author /i7>&ND.r
*/ [U+<uZzOC
public class CountBean { 2/a04qA#
private String countType; 7~Xu71^3s
int countId; C5W- B8>
/** Creates a new instance of CountData */ O V0cr
public CountBean() {} ?Mgt5by
public void setCountType(String countTypes){ P17]}F``
this.countType=countTypes; RMs1{64:
} A
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public void setCountId(int countIds){ 8.
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this.countId=countIds; }b\ipA,~
} *(_ON$+3
public String getCountType(){ -h.3M0
return countType; Rwi5+;N
} <#J<QYF&2
public int getCountId(){ Z:}2F^6
return countId; ]2u7?l
} =#PudF.\
} a*e|>p DO
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CountCache.java QvyUd%e'5A
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/* :;#c:RKi:
* CountCache.java yD=)&->Ra
* +LU ).
* Created on 2007年1月1日, 下午5:01 1dXO3hot
* iI/'!85
* To change this template, choose Tools | Options and locate the template under r.W"@vc>
* the Source Creation and Management node. Right-click the template and choose Jg?pW:}R
* Open. You can then make changes to the template in the Source Editor. x Ps&CyI
*/ ! a8h
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package com.tot.count; LOYyj?^7
import java.util.*; !'UsC6Y4
/** Iclan\q#y
* 'TEwU0<%
* @author WA)lk>(+
*/ 2{Lc^6i(t
public class CountCache { LVz%$Cq,0
public static LinkedList list=new LinkedList(); }9fV[zO
/** Creates a new instance of CountCache */
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public CountCache() {} M KE[Yb?
public static void add(CountBean cb){ <=LsloI
if(cb!=null){ 8~XI7g'5x
list.add(cb); {pi67"mYp
} B3i=pcef
} q'U-{~q%
} H#d! `
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CountControl.java 1QdB`8in
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/* Q-3J0=
* CountThread.java }F9?*2\/
* #)c;i<Q3S
* Created on 2007年1月1日, 下午4:57 :/?R9JVI
* Y$DgL
h
* To change this template, choose Tools | Options and locate the template under X/C54%T ~
* the Source Creation and Management node. Right-click the template and choose 1pBsr(
* Open. You can then make changes to the template in the Source Editor. 3 %{'Uh,
*/ %nK15(
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package com.tot.count; nD{;4$xP`
import tot.db.DBUtils; E`LIENm
import java.sql.*; 1=cfk#
/** ^a0-5
* gB'Ah -@,P
* @author OA5md9P;d
*/ T;vPR,]rz
public class CountControl{ &JzF
private static long lastExecuteTime=0;//上次更新时间 &-.eu
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 97=YFK~*
/** Creates a new instance of CountThread */ 1Yx[,GyC>&
public CountControl() {} ry<}DK<u
public synchronized void executeUpdate(){ )6S}O*
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Connection conn=null; {;rpgc
PreparedStatement ps=null; Xf/<.5A
try{ 7|?@\ZE
conn = DBUtils.getConnection(); [,V92-s;N
conn.setAutoCommit(false); 6P[O8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /[|md0,
for(int i=0;i<CountCache.list.size();i++){ ;$&5I9N
CountBean cb=(CountBean)CountCache.list.getFirst(); */m~m?
CountCache.list.removeFirst(); 2nz'/G
ps.setInt(1, cb.getCountId()); Q,+*u%/u
ps.executeUpdate();⑴ Gt*<?
//ps.addBatch();⑵ ,'0oj$~S:
} N`^W*>XB
//int [] counts = ps.executeBatch();⑶ KPvYq?F>4
conn.commit(); _1bd)L&dF
}catch(Exception e){ m##z
e.printStackTrace(); ~\(>m=|C:H
} finally{ ~k_zMU-1
try{ MnsWB[
if(ps!=null) { v-]-wNqT
ps.clearParameters(); rsj}hS$
ps.close(); ]m,p3
ps=null; a-A4xL.gm
} i!-sbwd7
}catch(SQLException e){} -D':7!@
DBUtils.closeConnection(conn); 9fLP&v
} h 7P?n.K
} +as\>"Cj+2
public long getLast(){ fv7g93
return lastExecuteTime; m l
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} PX{~! j%n
public void run(){ oN}j <6s
long now = System.currentTimeMillis(); &wC.?w$
if ((now - lastExecuteTime) > executeSep) { %LaC$w_X
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5m;wMW<
//System.out.print(" now:"+now+"\n"); zU=[Kc=$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +4vX+;: br
lastExecuteTime=now; B=xZkc
executeUpdate(); NjMLq|X
} H[yLlv
else{ Sgk{NM7|k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); %R5MAs&-5
} -]MP,P%
} tm#y`1-
} JS.'v7
//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 aWK7 -n
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类写好了,下面是在JSP中如下调用。 X-WvKH(=w
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<% dfd%A"
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CountBean cb=new CountBean(); B{u.Yc:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); F?4'>ZW
CountCache.add(cb); *qOCo_=P8
out.print(CountCache.list.size()+"<br>"); ;a77YLTQ
CountControl c=new CountControl(); &3/H
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c.run(); YLd%"H $n
out.print(CountCache.list.size()+"<br>"); *wx^mB9
%>