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: cD4H@!=a
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CountBean.java BxXP]od
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/* C@FX[:l@-
* CountData.java @arMg2"o
* X$$b :q
* Created on 2007年1月1日, 下午4:44 ?pp|~A)b
* -*"Q-GO
* To change this template, choose Tools | Options and locate the template under q+Qrc]>-f
* the Source Creation and Management node. Right-click the template and choose ~_yz\;#
* Open. You can then make changes to the template in the Source Editor. F,$ypGr
*/ |^kfa_d
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package com.tot.count; P'CDV3+
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/** <<ifd?
* zE4TdT1y|
* @author ,~xX[uB
*/ 5Og=`T
public class CountBean { A^hFRAg4
private String countType; hQDZ%>
int countId; hXsH9R
/** Creates a new instance of CountData */ VZ$FTM^b8
public CountBean() {} 3%SwCYd
public void setCountType(String countTypes){ >_um-w #C
this.countType=countTypes; g:>Mooxzi
} U6R~aRJ;
public void setCountId(int countIds){ 73d7'Fw
this.countId=countIds; i_qR&X
} R4g% $}
public String getCountType(){ zJa,kN|m
return countType; dWAKIBe
} "G
@(AE(
public int getCountId(){ x 3?:"D2
return countId; d<^o@
} Ax;i;<md
} -_|U"C$
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CountCache.java /\1MG>#K
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/* _^pg!j[Fy}
* CountCache.java #i~2C@]
* hA_Y@&=W
* Created on 2007年1月1日, 下午5:01 By-A1|4Cp`
* !9JK95;
* To change this template, choose Tools | Options and locate the template under 1K'.QRZMb9
* the Source Creation and Management node. Right-click the template and choose Oe*+pReSD
* Open. You can then make changes to the template in the Source Editor. 1k! xG$g0
*/ _;].
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package com.tot.count; P~"`Og+
import java.util.*; A~UDtXN*4
/** x_TtS|
* ,k5b,}tN
* @author G_UxR9Qo
*/ %4rPkPAtrp
public class CountCache { e^ygQ<6%
public static LinkedList list=new LinkedList(); s9-aPcA
/** Creates a new instance of CountCache */ F)g.xQ
public CountCache() {} 4TW>BA
public static void add(CountBean cb){ AmmUoS\
if(cb!=null){ 2K1odqO#
list.add(cb); #=B~}
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} BVpRkUC"
} L=wg"$
} hhVyz{u
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CountControl.java =9ISsI\Y6
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/* K 6Gri>Um
* CountThread.java fhZD[m#D
* ;0f?-W?1
* Created on 2007年1月1日, 下午4:57 'YcoF;&[C
* gqf*;Z eU
* To change this template, choose Tools | Options and locate the template under T] tG,W1>i
* the Source Creation and Management node. Right-click the template and choose [:!D.@h|
* Open. You can then make changes to the template in the Source Editor. hVAP
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*/ ekj@;6
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package com.tot.count; #D-L>7,jA
import tot.db.DBUtils; qs]7S^yw
import java.sql.*; $`&uu
/** >=_Z\ wA
* P|OjtI
* @author ,^UNQO*{GI
*/ `/mcjKQ&9y
public class CountControl{ iYJzSVO
private static long lastExecuteTime=0;//上次更新时间 M)oy3y^&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !?7c2QRN
/** Creates a new instance of CountThread */ >dW~o_u'QN
public CountControl() {} i$A0_ZJKjZ
public synchronized void executeUpdate(){ T53|*~u
Connection conn=null; /Af:{|'$%
PreparedStatement ps=null; D`bH_1X
try{ P'4jz&4
conn = DBUtils.getConnection(); mqg[2VTRP
conn.setAutoCommit(false); [o=v"s't)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^sNj[%I
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for(int i=0;i<CountCache.list.size();i++){ \666{. a
CountBean cb=(CountBean)CountCache.list.getFirst(); /k(KA [bS
CountCache.list.removeFirst(); "c6(=FFq
ps.setInt(1, cb.getCountId()); OBY
ps.executeUpdate();⑴ Y!6,ty'
//ps.addBatch();⑵ ]~SOGAFW
} m};Qng]
//int [] counts = ps.executeBatch();⑶ 'o#ve72z1
conn.commit(); D#T1~r4
}catch(Exception e){ d +Vx:`tT
e.printStackTrace(); :{d?B$
} finally{ $Y!$I.+
try{ _[,oP s:+
if(ps!=null) { 'Zdjd]
ps.clearParameters(); 1{sf Dw[s
ps.close(); /OpVr15
ps=null; zd+_
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} (\ze
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}catch(SQLException e){} cj:!uhZp7
DBUtils.closeConnection(conn); Ed%8| M3
} 5ap~;t
} h] (BTb#-
public long getLast(){ qd9CKd
return lastExecuteTime; YJlpP0;++
} "`Q.z~
public void run(){ v}v! hs Q
long now = System.currentTimeMillis(); /\S1p3EW*
if ((now - lastExecuteTime) > executeSep) { 4&Uq\,nx
//System.out.print("lastExecuteTime:"+lastExecuteTime); IQFt4{aK3
//System.out.print(" now:"+now+"\n"); j7vp@l6`L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); L+}q !'8S
lastExecuteTime=now; ^&'&Y>
executeUpdate(); )vFJx[a<n`
} wj fk >
else{ pr2b<(Pm
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p=Nord
} ubn`w=w$
} 3%<Uq%pJ
} L,&R0gxi
//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 H*DWDJxmV
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类写好了,下面是在JSP中如下调用。 tH_e?6]
^ $M@yWX6
<% HeagT(rN'
CountBean cb=new CountBean(); K; 7o+Xr
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !vU$^>zo~
CountCache.add(cb); L- -
out.print(CountCache.list.size()+"<br>"); %=:*yf>}
CountControl c=new CountControl(); Kp+Lk
c.run(); q][{?
out.print(CountCache.list.size()+"<br>"); *[Ld\lRj
%>