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: o0AREZ+I
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CountBean.java =x=#Etj|
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/* NKRNEq!
* CountData.java LdA&F&
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* gzeG5p
* Created on 2007年1月1日, 下午4:44 Ra.<D.
* 7dAa~!/(
* To change this template, choose Tools | Options and locate the template under &QvWT+]c'0
* the Source Creation and Management node. Right-click the template and choose ^!=+$@<
* Open. You can then make changes to the template in the Source Editor. 4PNl3N3,n
*/ .Zo8KwkFY
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package com.tot.count; ibEQ5 2
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/** d<xBI,g
* @dGj4h.
* @author GQq2;%RrF
*/ lE /"
public class CountBean { J PmW0wM
private String countType; h T4fKc7P
int countId; u" nyx0<
/** Creates a new instance of CountData */ tlc&Wx
public CountBean() {} i: 1V\q%
public void setCountType(String countTypes){ Tf` ~=fg%
this.countType=countTypes; o[_{\
} ?!b}Ir<1j
public void setCountId(int countIds){ UL(#B TK
this.countId=countIds; $6R<)]6
} |NL$? %I
public String getCountType(){ XBCz\f
return countType; \
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} {,,w5/k^
public int getCountId(){ 6:@tHUm
return countId; f ~9ADb
} UDhW Y.`'~
} 5X'[{'i,
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CountCache.java
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/* AS~O*(po
* CountCache.java H+ t^eg88
* 4?;1cXXA
* Created on 2007年1月1日, 下午5:01 BoXQBcG]w
* I@e{>}
* To change this template, choose Tools | Options and locate the template under 5yuR[VU
* the Source Creation and Management node. Right-click the template and choose nx84l 7<
* Open. You can then make changes to the template in the Source Editor. [26"?};"%
*/ LC2t,!RRl&
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package com.tot.count; [
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import java.util.*; PO1sVP.S
/** 8nW#Q<s
* 1Sr@$+VGO
* @author MX]<tR `
*/ uee2WGD
public class CountCache { \f05(ld
public static LinkedList list=new LinkedList(); &K/5AH"q
/** Creates a new instance of CountCache */ kF`2%g+
public CountCache() {} Y}Y2Vx
public static void add(CountBean cb){ !'[f!vsyM{
if(cb!=null){ ^dld\t:tV7
list.add(cb); Jr|"` f%V
} vQ$ FMKz7
} $s5LzJn
} C&D!TR!K
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CountControl.java YOd0dKe
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/* }]'Z~5T
* CountThread.java ['Hl$2 j
* 0PjWfM8%
* Created on 2007年1月1日, 下午4:57 \GEFhM4)
* -$>R;L
* To change this template, choose Tools | Options and locate the template under LY-fp+
* the Source Creation and Management node. Right-click the template and choose QQj)"XJ29
* Open. You can then make changes to the template in the Source Editor. ?v\A&d
*/ IR(qjm\V
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package com.tot.count; km|;T!
import tot.db.DBUtils; q{nNWvL
import java.sql.*; /q0[T{Wz$
/** jA?A)YNQb
* P|Dw+lQj
* @author \GO^2&g(
*/ S=*rWh8)%<
public class CountControl{ 7LbBS:@3z_
private static long lastExecuteTime=0;//上次更新时间 <-D>^p9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 OTY9Q
/** Creates a new instance of CountThread */ Usx8
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public CountControl() {} xrs?"]M[
public synchronized void executeUpdate(){ :<r.n
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Connection conn=null; ]6bh #N;.
PreparedStatement ps=null; +mIO*UQi
try{ v[E*K@6f
conn = DBUtils.getConnection(); L'iENZI$
conn.setAutoCommit(false); tURjIt,I
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @G@,)`p4?
for(int i=0;i<CountCache.list.size();i++){ )v
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CountBean cb=(CountBean)CountCache.list.getFirst(); J^m#984
CountCache.list.removeFirst(); %}elh79H*
ps.setInt(1, cb.getCountId()); e$u=>=jV]
ps.executeUpdate();⑴ '_N~PoV
//ps.addBatch();⑵ .B_LQ;0:
} jdqVS @SD
//int [] counts = ps.executeBatch();⑶ 6vAq&Y{JB'
conn.commit(); *](maF~%C
}catch(Exception e){ hd^?mZ
e.printStackTrace(); x1VBO.t=*
} finally{ >x]b"@Hkw
try{ CoO..
if(ps!=null) { gi\2bzWkbX
ps.clearParameters(); :m#[V7
ps.close(); c>!zJAB
ps=null; *-'u(o
} T a8;
}catch(SQLException e){} 1zqIB")s>
DBUtils.closeConnection(conn); +m8CN(c
} ZfsM($|a
} 7}>Zq`]~
public long getLast(){ j}t"M|`
return lastExecuteTime; _IYd^c
} T#KF@8'-
public void run(){ <#/r.}.x
long now = System.currentTimeMillis(); (&t741DN|
if ((now - lastExecuteTime) > executeSep) { #;~`+[y?\
//System.out.print("lastExecuteTime:"+lastExecuteTime); }-jS0{i
//System.out.print(" now:"+now+"\n"); 8S/SXyS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *'[8FZ|dQ
lastExecuteTime=now; @-ps[b`z
executeUpdate(); Hj(ay48
} Lu?MRF
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else{ }x!=F<Q!r
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]z3!hgTj
} >n3w'b
} uy'm2
} G8AT]
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//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 paCC'*bv
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类写好了,下面是在JSP中如下调用。 oHh~!#u
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<% m03D+@F
CountBean cb=new CountBean(); f4[fXP;A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @N+ }cej
CountCache.add(cb); NN>E1d=
out.print(CountCache.list.size()+"<br>"); fz>3
CountControl c=new CountControl(); VS`
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c.run(); ]6s7?07m4
out.print(CountCache.list.size()+"<br>"); |p_\pa1&
%>