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: kV_#9z7%
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CountBean.java *Yj~]E0`1
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/* 5r^1CFO
* CountData.java p(~Y"
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* yI3Q |731)
* Created on 2007年1月1日, 下午4:44 JL?Cnk$!
* mXQl;
* To change this template, choose Tools | Options and locate the template under w'!ECm>*`
* the Source Creation and Management node. Right-click the template and choose &$<(D0
* Open. You can then make changes to the template in the Source Editor. *Kp}B}}J
*/ g[m3IJzq
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package com.tot.count; z Z@L4ZT
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/** 2T//%ys=
* @>M8Pe
* @author &/sGh0
*/ oK#\HD4U
public class CountBean { LKIW*M
private String countType; DLNa6
int countId; olYPlHF
/** Creates a new instance of CountData */ yJF 2
public CountBean() {} #.<*; rB
public void setCountType(String countTypes){ FYp|oD2=1
this.countType=countTypes; gsLr=
} jK\V|5k
public void setCountId(int countIds){ "}0)YRz%
this.countId=countIds; +R2^*
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} \Y51KB\
public String getCountType(){ I~d#p ]>
return countType; F9Ifw><XM
} 's$A+8;L
public int getCountId(){ NE$VeW+@
return countId; #=`FM:WH
} '9IP;
} zY]Bu-S3
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CountCache.java @*CAn(@#N
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/* R#"U/8b>z
* CountCache.java %T`4!:vy
* q:TZ=bs^
* Created on 2007年1月1日, 下午5:01 ]]\)=F`n77
* .tZjdNE(h
* To change this template, choose Tools | Options and locate the template under cYZwWMzp
* the Source Creation and Management node. Right-click the template and choose J!=](s5|
* Open. You can then make changes to the template in the Source Editor. !T<z'zZU
*/ `
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package com.tot.count; )9;(>cdl
import java.util.*; R2Twm!1
/** C>.]Bvg
* Py|H?
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* @author i0,%}{`
*/ C_;HaQiu
public class CountCache { <{$ev&bQ
public static LinkedList list=new LinkedList(); 2>!_B\%) H
/** Creates a new instance of CountCache */ KU1+<OCh
public CountCache() {} b}ySZlmy
public static void add(CountBean cb){ cxtLy&C
if(cb!=null){ "WF(
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list.add(cb); >{O[t2&
} l@,); w=_P
} g0^~J2sDd
} >Sc$R0
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CountControl.java yf
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/* xaGVu0q
* CountThread.java T^/Gj|N*
* xB?S#5G}
* Created on 2007年1月1日, 下午4:57 JIyBhFI
* ddUjs8VvJ
* To change this template, choose Tools | Options and locate the template under `U{o:
* the Source Creation and Management node. Right-click the template and choose {toyQ)C7
* Open. You can then make changes to the template in the Source Editor. qR [}EX&3
*/ =q_&*'
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package com.tot.count; Ft3N#!ubl
import tot.db.DBUtils; Ck ~V5
import java.sql.*; t]
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/** PphR4 sIM
* Eg@R[ ^T
* @author =$"zqa.B6
*/
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public class CountControl{ ~[d=s
private static long lastExecuteTime=0;//上次更新时间 Nb^zkg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /3)YWFZZc
/** Creates a new instance of CountThread */ u~/M
public CountControl() {} }XfS#Xr1aV
public synchronized void executeUpdate(){
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Connection conn=null; 5]4<!m
PreparedStatement ps=null; s`8M%ZLu
try{ OYqYI!N/
conn = DBUtils.getConnection(); L Q I: ]d
conn.setAutoCommit(false); )
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Bq$e|t)'
for(int i=0;i<CountCache.list.size();i++){ -4*'WzWr
CountBean cb=(CountBean)CountCache.list.getFirst(); s=^r/Sz902
CountCache.list.removeFirst(); z;fd#N:
ps.setInt(1, cb.getCountId()); l}2%?d
ps.executeUpdate();⑴ Vu|Br
//ps.addBatch();⑵ -V;0_Nx7p
} )8 "EI-/.
//int [] counts = ps.executeBatch();⑶ 'k-u9
conn.commit(); <|KKv5[
}catch(Exception e){ ]MqH13`)A
e.printStackTrace(); w8m8r`h
} finally{ @e.OU(Bf
try{ jV,(P$ 5;
if(ps!=null) { V e$5w}a4
ps.clearParameters(); "oE^R?m
ps.close(); 2fj0 I
ps=null; /%ODJ1 M
} Z,|1G6f@
}catch(SQLException e){} f_re"d 3u
DBUtils.closeConnection(conn); 5{R#h :
} dI#8CO
} M5cOz|j/*R
public long getLast(){ `_ J^g&y~
return lastExecuteTime; b2/N H1A
}
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public void run(){ 7"a`-]Ap
long now = System.currentTimeMillis(); APHtJoS
if ((now - lastExecuteTime) > executeSep) { +!L_E6pyXE
//System.out.print("lastExecuteTime:"+lastExecuteTime); g:.,}L
//System.out.print(" now:"+now+"\n"); *O(/UVuD\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |
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lastExecuteTime=now; ecY ^C3+S
executeUpdate(); @n~>j&Kp
} 4i[v
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else{ &J6o$i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RS||KA])J
} Q
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} !
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} (l3UNP
//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 n3l"L|W^(<
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类写好了,下面是在JSP中如下调用。 I |<+'G
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<% L6[rvM|9_
CountBean cb=new CountBean(); L5zG0mC8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); DK@w^ZW6JA
CountCache.add(cb); e~t}z_>F
out.print(CountCache.list.size()+"<br>"); :"<B@Z
CountControl c=new CountControl(); Ry8WNVO}R
c.run(); d}wa[WRv
out.print(CountCache.list.size()+"<br>"); =& Tu`m
%>