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: s^SU6P/]
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CountBean.java qp/1tC`
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/* bJ2>@|3*
* CountData.java Dr(2@0P
* MG~Z)+g=y
* Created on 2007年1月1日, 下午4:44 a!/\:4-uc
* X 6tJ
* To change this template, choose Tools | Options and locate the template under ;6D3>Lm
* the Source Creation and Management node. Right-click the template and choose JN4gH4ez)
* Open. You can then make changes to the template in the Source Editor. e^3D`GA
*/ ('Qq"cn#
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package com.tot.count; |m6rF7Q
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/** 0nL
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* &VA^LS@b
* @author 71Za!3+
*/ pgiZA?r*<
public class CountBean { 2O*At%CzW
private String countType; LTo5v
int countId; F8dr-"G
/** Creates a new instance of CountData */ 8>W52~^fU
public CountBean() {} Du65>O
public void setCountType(String countTypes){ 8h }a:/
this.countType=countTypes; qg=`=]j
} {?Y\T
public void setCountId(int countIds){ r5ldK?=k+*
this.countId=countIds; "uT2 DY[
} Y0krFhL'x0
public String getCountType(){ h@\-]zN{
return countType; {:*G/*1[.
} m_CWVw
public int getCountId(){ ?bt;i>O\
return countId; YY :{/0?
} yn$1nt4
} iE
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CountCache.java pe0ax-Zv
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/* T4Vp0i
* CountCache.java
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* R]e&JoY
* Created on 2007年1月1日, 下午5:01 Z37Dv;&ZD
* dor1(@no|
* To change this template, choose Tools | Options and locate the template under |LZ{kD|
* the Source Creation and Management node. Right-click the template and choose iu(obmh/o
* Open. You can then make changes to the template in the Source Editor. ,Yx<"2 W
*/ #b;k+<n[X
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package com.tot.count;
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import java.util.*; E:B"!Y6
/** %&&)[
* !j`<iPI7B
* @author UkpTK8>&
*/ >
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public class CountCache { BYMdX J
public static LinkedList list=new LinkedList(); 6E
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/** Creates a new instance of CountCache */
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public CountCache() {} -dO8Uis$
public static void add(CountBean cb){ q4w]9b/
if(cb!=null){ p+|8(w9A${
list.add(cb); A+8)VlE\
} ;$zvm`|:
} .Z'NH
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} \%Y`>x.
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CountControl.java VBPtM{g
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/* |8~)3P k
* CountThread.java k(^TXUK\o
* |v8hg])I+
* Created on 2007年1月1日, 下午4:57 &
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* ym%` l!
* To change this template, choose Tools | Options and locate the template under #}B1W&\sw
* the Source Creation and Management node. Right-click the template and choose J.XhP_aT
* Open. You can then make changes to the template in the Source Editor. <uB)u>3
*/ }DM W,+3
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package com.tot.count; GvG8s6IZ
import tot.db.DBUtils; L~{(9J'(
import java.sql.*; ukEJ D3i
/** ;lb
* PNo:[9`S;m
* @author ]?H12xz
*/ -K?lhu
public class CountControl{ ^*`#+*C
private static long lastExecuteTime=0;//上次更新时间 CN ( :
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0Zwx3[bq6K
/** Creates a new instance of CountThread */ qhvT,"
public CountControl() {} 3{|~'5*
public synchronized void executeUpdate(){ p *42
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Connection conn=null; ,(Zxd4?y
PreparedStatement ps=null; ; 8DtnnE
try{ 2"Wq=qy\J
conn = DBUtils.getConnection(); q MrM^ ~
conn.setAutoCommit(false); Ul/m]b6-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); F7O*%y.';
for(int i=0;i<CountCache.list.size();i++){ 4]m{^z`1
CountBean cb=(CountBean)CountCache.list.getFirst(); dWkQ NFKF
CountCache.list.removeFirst(); 'A.5T%n-
ps.setInt(1, cb.getCountId()); e,p*R?Y{[
ps.executeUpdate();⑴ [(_,\:L${
//ps.addBatch();⑵ ,)*[Xa_n
} aWJ
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//int [] counts = ps.executeBatch();⑶ PkyX,mr#1
conn.commit(); i&lW&]
}catch(Exception e){ OYt_i'Q
e.printStackTrace(); 4hxP`!<
} finally{ S-o)d
try{ L-E?1qhP>
if(ps!=null) { q x1Js3%
ps.clearParameters(); _[z)%`kay
ps.close(); .rO~a.kG
ps=null; 2bTS,N/>
} syg{qtBz^
}catch(SQLException e){} 3e^0W_>6
DBUtils.closeConnection(conn); yH-&o,
} !Whx^B:
} K)
public long getLast(){ qGH[kd
return lastExecuteTime; lMu9Dp
} 9y&;6V.'
public void run(){ Xw'sh#i2
long now = System.currentTimeMillis(); $8U$.~v
if ((now - lastExecuteTime) > executeSep) { m-\_L=QzM
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^j${#Q
//System.out.print(" now:"+now+"\n"); Cq/u$G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); n:wAxU
lastExecuteTime=now; _;5zA"~c#@
executeUpdate(); q?mpvpLG
} "IQYy~
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else{ xS%&l)dT
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Io JI|lP
} .wq
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} 0lniu=xmQ-
} 8g)$%Fy+N
//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 zF^H*H
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类写好了,下面是在JSP中如下调用。 ]!sCWR
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<% ]!^wB 3j
CountBean cb=new CountBean(); "@^<~bw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -Q J8\/1>
CountCache.add(cb); hy;V~J#
out.print(CountCache.list.size()+"<br>"); FO[ s;dmzu
CountControl c=new CountControl(); B.od{@I(Xp
c.run(); F7jkl4
out.print(CountCache.list.size()+"<br>"); =J)-#|eZG
%>