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: K Hc +
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CountBean.java (HxF\#r?
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/* vGDo?X~#o
* CountData.java 9^olAfX`dB
* xb;mm9H
* Created on 2007年1月1日, 下午4:44 MPc=cLv
* uwzT? C A6
* To change this template, choose Tools | Options and locate the template under K>6p5*&
* the Source Creation and Management node. Right-click the template and choose SW,Po>Y
* Open. You can then make changes to the template in the Source Editor. a^,RbV/
*/ }A^,y
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package com.tot.count; |0mI3r
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/** K@hUif|([
* &9{BuBO[
* @author oPBjsQ
*/ x=)$sD-3
public class CountBean {
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private String countType; _XPc0r:?>
int countId; u&bU !ZI
/** Creates a new instance of CountData */ tsD^8~
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public CountBean() {} vL0Ol-Vt
public void setCountType(String countTypes){ :Aw VeX@
this.countType=countTypes; xb\:H@92
} EUqG"h5#A{
public void setCountId(int countIds){ z`SkKn0f
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this.countId=countIds; [t'"4
} \:7EKzQ
public String getCountType(){ //|Vj | =
return countType; Hq$|j,&?
} 2T9Z{v
public int getCountId(){ ^Quy64M
return countId; RJD3o_("K
} U4JN,`p{
} ] fB{
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CountCache.java 8E{>czF"
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/* A\Gw+l<h,
* CountCache.java RwWQ$Eb_s
* lla96\R
* Created on 2007年1月1日, 下午5:01 "
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* <ZEA&:p
* To change this template, choose Tools | Options and locate the template under AtI,&S#{
* the Source Creation and Management node. Right-click the template and choose {VG6m
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* Open. You can then make changes to the template in the Source Editor. R2@u[
*/ t,_[nu(~8%
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package com.tot.count; VXS9E383
import java.util.*; 1,,-R*x
/** =UY@,*q:c
* S{6u\Vy
* @author `<q5RuU
*/ 1wt]J!hgV
public class CountCache { X*Zv,Wm
public static LinkedList list=new LinkedList(); $)!Z"2T
/** Creates a new instance of CountCache */ r^)<Jy0|r
public CountCache() {} =B1!em|
public static void add(CountBean cb){ clNP9{
if(cb!=null){ jC%I]#!n
list.add(cb); ! ZEKvW
} /_\4(vvf
} /Y:Zqk3
}
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CountControl.java ;f
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/* 2Z~ofrj
* CountThread.java gN%R-e0
* `Ec+i
* Created on 2007年1月1日, 下午4:57 MZ'HMYed
* C'ZU .Y
* To change this template, choose Tools | Options and locate the template under {YFru6$
* the Source Creation and Management node. Right-click the template and choose ||f4f3R'
* Open. You can then make changes to the template in the Source Editor. 4.TG&IQ
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*/ U' Cp3>
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package com.tot.count; <3KrhhH
import tot.db.DBUtils; ;<\*(rUe
import java.sql.*; @Klj!2cv$
/** mwxJ#
* 5|Qr"c$p
* @author dq2v[?*R
*/ c1[;a>
public class CountControl{ SW7%SX,xM
private static long lastExecuteTime=0;//上次更新时间 .kVga+la?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ) =[Tgh
/** Creates a new instance of CountThread */ 0U'r ia:$
public CountControl() {} <,{v>vlw
public synchronized void executeUpdate(){ R[QE:#hT
Connection conn=null; rk|6!kry
PreparedStatement ps=null; jolCR-FDu
try{ <Vim\
conn = DBUtils.getConnection(); ]+AI:
conn.setAutoCommit(false); $1e@3mzM
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); H\T
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for(int i=0;i<CountCache.list.size();i++){ `8I&(k<wLe
CountBean cb=(CountBean)CountCache.list.getFirst(); @OpcS>:R
CountCache.list.removeFirst(); ;
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ps.setInt(1, cb.getCountId()); Hi Yx(hY
ps.executeUpdate();⑴ %}/)_RzQ
//ps.addBatch();⑵ n2E2V<#
} hf[K\aAk
//int [] counts = ps.executeBatch();⑶ S`::f(e
conn.commit(); 7j+.H/2
}catch(Exception e){ t%)L8%Jr
e.printStackTrace(); vzL>ZBeZ
} finally{ ]#nAld1cmy
try{ <FP-]R)
if(ps!=null) { Xp'KQ1w)
ps.clearParameters(); {R K#W~h
ps.close(); rTH@PDk>)
ps=null; _R]h]<TQ
} 7?Fl [FW$
}catch(SQLException e){} QO8/?^d
DBUtils.closeConnection(conn);
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} W6pS.}
} jV(ISD
public long getLast(){ B~^\jRd"
return lastExecuteTime; ^JTfRZ:a
} %UmE=V
public void run(){ bnlL-]]9z
long now = System.currentTimeMillis(); R~`Y6>o~9:
if ((now - lastExecuteTime) > executeSep) { gVGq
//System.out.print("lastExecuteTime:"+lastExecuteTime); G 6][@q
//System.out.print(" now:"+now+"\n"); z#y<QH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -I -wdyDr
lastExecuteTime=now; -$7Jc=:>
executeUpdate(); /<mc~S7
} \sk,3b-&'
else{ [-l^,,E
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Uc4r
} e"vEh
} eu#| |
} m'pihFR:f
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 \ .:CL?m#
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类写好了,下面是在JSP中如下调用。 Ct B>
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<% W?@ ;(k
CountBean cb=new CountBean(); 7l?=$q>k"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); k=LY 6
CountCache.add(cb); HwDb &pP"
out.print(CountCache.list.size()+"<br>"); +G?3j ,a\
CountControl c=new CountControl(); )T>a|.
c.run(); 3}"VUS0wh
out.print(CountCache.list.size()+"<br>"); <Sz9: hg-
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