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: `R@1Sc<*|
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CountBean.java `6a
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/* gE$D#PZa
* CountData.java xi|T7,\X
* c:(Xkzj
* Created on 2007年1月1日, 下午4:44 LUSBRr8
* k I
* To change this template, choose Tools | Options and locate the template under (/TYET_H
* the Source Creation and Management node. Right-click the template and choose xwK{}==U
* Open. You can then make changes to the template in the Source Editor. 3Au3>q,
*/ SPfz/ q{
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package com.tot.count; m{T:<:q~
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/**
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* *HiN:30DZ
* @author wq$+m(
*/ ?:DeOBAb
public class CountBean { KQGdV{VFs
private String countType; BZHba8c(
int countId; )5n*4A
/** Creates a new instance of CountData */ V0 70oZ
public CountBean() {} BN??3F8C
public void setCountType(String countTypes){
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this.countType=countTypes; ]\DZW4?'
} [t#xX59
public void setCountId(int countIds){ 8NCu;s
this.countId=countIds; !R@v\Eu
} (55k70>i3
public String getCountType(){ G)~/$EF,_
return countType; a`/\0~
} >Pa&f20Hp
public int getCountId(){ IZ?+c@t
return countId; j{ QzD^t
} CshYUr -
} [_kis
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CountCache.java v+\&8)W=
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/* R^u 1(SF
* CountCache.java O7D aVlln
* n{'LF #4l
* Created on 2007年1月1日, 下午5:01 vH14%&OcN
* );*:UzsC_
* To change this template, choose Tools | Options and locate the template under :Y4m3|
* the Source Creation and Management node. Right-click the template and choose >+}yI}W;e
* Open. You can then make changes to the template in the Source Editor. E}-Y!,v^
*/ D1G9^7:^E
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package com.tot.count; rnNB!T
import java.util.*; 4v[Zhf4JM
/** z[vHMJ
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* +"P!es\q
* @author EhWYFQ
*/ pAdx 6
public class CountCache { Twq/Y07M
public static LinkedList list=new LinkedList(); -!Ov{GHr0
/** Creates a new instance of CountCache */ sKu/VAh
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public CountCache() {} GN0s`'#"3%
public static void add(CountBean cb){ Cpg>5N~;L
if(cb!=null){ `2
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list.add(cb); J_-K"T|f
} {KQ]"a 6
} 85e!)I_
} P:8qmDXo
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CountControl.java /+
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/* bf4QW JZD
* CountThread.java A!GQ4.~%
* k[ZkVwx
* Created on 2007年1月1日, 下午4:57 hiT&QJB` _
* H@|h
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* To change this template, choose Tools | Options and locate the template under 8u|F %Sg
* the Source Creation and Management node. Right-click the template and choose b=$(`y
* Open. You can then make changes to the template in the Source Editor. q0t}
*/ 6B8gMO
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package com.tot.count; z79c30y]"
import tot.db.DBUtils; BmhIKXE{*
import java.sql.*; _48@o^{
/** zm~sq_=^
* 9YQYg@+R
* @author G4<M@ET
*/ +"?O2PX
public class CountControl{ Z%4w{T+[
private static long lastExecuteTime=0;//上次更新时间 Oaj$Z-
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ (8Inf_59
public CountControl() {} ]8o[&50y
public synchronized void executeUpdate(){ e8,!x9%J
Connection conn=null; YiGSFg
PreparedStatement ps=null; &P:2`\'
try{ uXuA4o$t-
conn = DBUtils.getConnection(); s2kom)
conn.setAutoCommit(false); Fi8#r)G.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n4A#T#D!t3
for(int i=0;i<CountCache.list.size();i++){ ]_js-+w6
CountBean cb=(CountBean)CountCache.list.getFirst(); W*WSjuFr2
CountCache.list.removeFirst(); EC8 Fapy
ps.setInt(1, cb.getCountId()); Qj3l>O
ps.executeUpdate();⑴ 8{B]_:
-:
//ps.addBatch();⑵ $ISx0l~
} _t-e.2a
v
//int [] counts = ps.executeBatch();⑶ N2.(0 G
conn.commit(); kE[Hq-J=N
}catch(Exception e){ c`s ]ciC
e.printStackTrace(); H$)__V5I,q
} finally{ P
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try{ <(tnClAn
if(ps!=null) { 6}JW- sA
ps.clearParameters(); f7v|N)
ps.close(); []<N@a6VA>
ps=null; DP6>fzsl
} }!^`%\ %\
}catch(SQLException e){} r"$~Gg.%(
DBUtils.closeConnection(conn); XtftG7r9S
} >k9W+mk
} 5J2tR6u-(
public long getLast(){ fqm-?vy}
return lastExecuteTime; *5z"Xy3J
} K06x7W
public void run(){ As+^6
long now = System.currentTimeMillis(); @p[ml m
if ((now - lastExecuteTime) > executeSep) { X*<
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//System.out.print("lastExecuteTime:"+lastExecuteTime); i-M<_62c
//System.out.print(" now:"+now+"\n"); (_n U}<y_i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &pFP=|Pq
lastExecuteTime=now; %d^ =$Q
executeUpdate(); LA4,o@V`
} vT;~\,M
else{ Cm%xI&Y
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7*(K%e"U
} 9D{p^hd
} ;.I,R NM
} lnWscb3t
//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 =y]FcxF
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类写好了,下面是在JSP中如下调用。 +z O.|`+
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<% \xjI=P'-25
CountBean cb=new CountBean(); _r?.%]\.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m~R Me9Qi
CountCache.add(cb); / TAza9a
out.print(CountCache.list.size()+"<br>"); Rc#c^F<
CountControl c=new CountControl(); ?X nKKw\
c.run(); #<81`%
out.print(CountCache.list.size()+"<br>"); LPS]TG\
%>