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: ib8@U}Vn1
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CountBean.java qELy'\
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/* [;yEG$)K
* CountData.java rkOLTi[$
* $2N)m:X0
* Created on 2007年1月1日, 下午4:44 }: v&Nc
* I\eM8`Y$
* To change this template, choose Tools | Options and locate the template under oqeA15k$
* the Source Creation and Management node. Right-click the template and choose /~RY{ c@#L
* Open. You can then make changes to the template in the Source Editor. {T EF#iF
*/ CsfGjqpf
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package com.tot.count; .;#Wf@V
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/** imGg3'
* K]5@bm
* @author 701ei;
*/
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public class CountBean { h$3o]~t
private String countType; K1i@.`na/$
int countId; BC|=-^(
/** Creates a new instance of CountData */ x93t.5E6
public CountBean() {} X;[$yW9hE
public void setCountType(String countTypes){ h0i/ v
this.countType=countTypes; `1;m:,9
} Ll4/P[7:?
public void setCountId(int countIds){ )?es3Ehqq
this.countId=countIds; pGS!Nn;K2
} >/W
public String getCountType(){ <:(pnw*L
return countType; of? hP1kl[
} H?\b
public int getCountId(){ tb#9TF
return countId; Q)`3&b
} D}.Pk>5
} E]T>m!6
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CountCache.java 8OV;&Z,x
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/* wlSl ~A/s
* CountCache.java Nu}x`Qkmr
* "$@>n(w
* Created on 2007年1月1日, 下午5:01 FBDRb J
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* j`
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* To change this template, choose Tools | Options and locate the template under R;XG2
* the Source Creation and Management node. Right-click the template and choose HhZlHL
* Open. You can then make changes to the template in the Source Editor. k
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*/ #RfNk;kaA
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package com.tot.count; kMJf!%L (
import java.util.*; ^v5v7\!
/** ]6)~Sj$ 5
* fv;3cxQp
* @author |<:Owd=
*/ U"SH
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public class CountCache { SK6?;_
public static LinkedList list=new LinkedList(); F},#%_4
/** Creates a new instance of CountCache */ Hj\iI p
public CountCache() {} J #ukH`|-
public static void add(CountBean cb){ 9YMD[H\}V
if(cb!=null){ bQTkW<7gh
list.add(cb); nu=yE$BN{
} __B`0t
} Rix|LKk{
} 2b&&3u8
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CountControl.java htgtgW9
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/* M&93TQU-
* CountThread.java !L|}/u3v
* lla ?;^,
* Created on 2007年1月1日, 下午4:57 te<lCD6
* zYCS K~-GW
* To change this template, choose Tools | Options and locate the template under NZ{)&ObBRt
* the Source Creation and Management node. Right-click the template and choose t@ _MWF
* Open. You can then make changes to the template in the Source Editor. &1ZqC;
*/ By&ibN),
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package com.tot.count; tAi
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import tot.db.DBUtils; sYMgi D
import java.sql.*; k Q
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/** WVa-0;
* ^9jrI
* @author [?QU'[
*/ KscugX*x
public class CountControl{ 3EVAB0/$
private static long lastExecuteTime=0;//上次更新时间 BQOit.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 I1Jhvyd?$
/** Creates a new instance of CountThread */ Z<Rhn
public CountControl() {} _Hp[}sv4)
public synchronized void executeUpdate(){ Yg~$1b@
Connection conn=null; bE6:pGr
PreparedStatement ps=null; *vqr+jr9
try{ :(?F(Q^
conn = DBUtils.getConnection(); VhfMj|
conn.setAutoCommit(false); TF[8r[93
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); N -z
for(int i=0;i<CountCache.list.size();i++){ R?Dc*,
CountBean cb=(CountBean)CountCache.list.getFirst(); izvwXC
CountCache.list.removeFirst(); l5/!0]/
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ Q)s`~G({P
//ps.addBatch();⑵ Zr#\>h 'c
} |ctcY*+
//int [] counts = ps.executeBatch();⑶ c H7Gb|,M
conn.commit(); m\DI6O"u'
}catch(Exception e){ Lk>GEi|
e.printStackTrace(); LJ{P93aq`^
} finally{ 6!|/(~
try{ TGSkJ 1Lx
if(ps!=null) { 2zlBrjk;
ps.clearParameters(); Qw@_.I
ps.close(); Yp@i{$IUW
ps=null; #*zl;h1(
} 9l&4mt;+&<
}catch(SQLException e){} wj$WE3Y
DBUtils.closeConnection(conn); `%<^$Ng;
} $%"?0S
} T[\?fSP
public long getLast(){ g54b}vzm
return lastExecuteTime; $8;`6o`
} N_Q\+x}zq
public void run(){ nN*:"F/^
long now = System.currentTimeMillis(); ?Mj@;O9>'
if ((now - lastExecuteTime) > executeSep) { Xt$o$V
//System.out.print("lastExecuteTime:"+lastExecuteTime); i!7|YAu
//System.out.print(" now:"+now+"\n"); H"vy[/UcR
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); CGCI3Z'
lastExecuteTime=now; 0w9[Z
executeUpdate(); ,5Nf9z!hk(
} 7dq*e4z)
else{ g7g^iLU
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0NFYFd-50
} =&-+{txs
} Sf"]enwB
} Sft+Gb6
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 rI;84=v2&9
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类写好了,下面是在JSP中如下调用。 2)^gd
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<% cwC-)#R']
CountBean cb=new CountBean(); 90[?)s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >u/ T`$
CountCache.add(cb); |9x H9@^f
out.print(CountCache.list.size()+"<br>"); 4PDxmH]y
CountControl c=new CountControl(); *)0-N!N#)
c.run(); d7i 0'R
out.print(CountCache.list.size()+"<br>"); j" ~gEGfK
%>