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: [)6E)E`_e
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CountBean.java 8jGoU9
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/* WK)k -A^q
* CountData.java R.'Gg
* _p2<7x i
* Created on 2007年1月1日, 下午4:44 2Xs < 1rF
* $"n)C
* To change this template, choose Tools | Options and locate the template under <=2*UD |
* the Source Creation and Management node. Right-click the template and choose k*6eZ 7
* Open. You can then make changes to the template in the Source Editor. /2V',0
*/ Wv/5#_
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package com.tot.count; A-!qO|E[-
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/** fTtSx_}3H
* vjRD?kF
* @author 6}lEeMRW
*/ Q>g$)-8
public class CountBean { R*G>)YH
private String countType; H0NyxG<
int countId; dY`J,s
/** Creates a new instance of CountData */ Ijro;rsEKM
public CountBean() {} PCnJ2
public void setCountType(String countTypes){ E1w XG
this.countType=countTypes; D)cwttH
} ZGvNEjff
public void setCountId(int countIds){ #@"rp]1xv
this.countId=countIds; >ZsK5v
} w7V
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public String getCountType(){ S2SQ;s-t_
return countType; Z'bMIdV
} {v/6|
public int getCountId(){ <rmV$_
return countId; YVp0}m
} :2gO)
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} ]-LE'Px|
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CountCache.java Px&Mi:4tG
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/* mU>*NP(L
* CountCache.java ;| ,Y2?
* 3H%WB|
* Created on 2007年1月1日, 下午5:01 LB+=?Mz V
* %b4(wn?n:B
* To change this template, choose Tools | Options and locate the template under b#j5fEY
* the Source Creation and Management node. Right-click the template and choose d/QM
* Open. You can then make changes to the template in the Source Editor. j".6
*/ [kkcV5I-
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package com.tot.count; M<pgaB0
import java.util.*; ?y@pRe$2
/** DTVnQC
* qiJ{X{lI
* @author DdBrJ x
*/ YZ
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public class CountCache {
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public static LinkedList list=new LinkedList(); ..mz!:Zs0
/** Creates a new instance of CountCache */ _J;a[Ky+[
public CountCache() {} - & r{%7
public static void add(CountBean cb){ 9DE)5/c`v
if(cb!=null){ l6Bd<tSH
list.add(cb); Bn:sN_N
} >;?97'M
} <2A'
} 7^X_tQf
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CountControl.java B6&Mtm1
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/* t4uxon
* CountThread.java }epN<DL
* r{&"]'/X
* Created on 2007年1月1日, 下午4:57 "//
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* LK~0ck7
* To change this template, choose Tools | Options and locate the template under `q*ABsj
* the Source Creation and Management node. Right-click the template and choose }1 ^.A84a
* Open. You can then make changes to the template in the Source Editor. ~;Kl/Z
*/ IW*.B6Hw8
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package com.tot.count; 8;rS"!qM
import tot.db.DBUtils; 3W0:0I
import java.sql.*; FM];+d0
/** tgnXBWA`!
* 9Ua@-
* @author /% 1lJD
*/ ]h@:Y]
public class CountControl{ OSU=O
private static long lastExecuteTime=0;//上次更新时间 "rJL ^ \r
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4ebGAg ?_
/** Creates a new instance of CountThread */ 5o#8DIal
public CountControl() {} _;W|iUreb
public synchronized void executeUpdate(){ }qPo%T
Connection conn=null; ]uf_"D
PreparedStatement ps=null; P*]g*&*Y +
try{ GjBQxn
conn = DBUtils.getConnection(); R?I3xb
conn.setAutoCommit(false); +__Rk1CVh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S0yT%V
for(int i=0;i<CountCache.list.size();i++){ uM#/
CountBean cb=(CountBean)CountCache.list.getFirst(); T94$}- 5/)
CountCache.list.removeFirst(); 1qF.0
ps.setInt(1, cb.getCountId()); +^:K#S9U
ps.executeUpdate();⑴ 1cega1s3xR
//ps.addBatch();⑵ HR
} u{ /gjv
//int [] counts = ps.executeBatch();⑶ SYx)!n6U
conn.commit(); Mk;j"ZDF
}catch(Exception e){ 0}N^l=jQ
e.printStackTrace(); Fsh-a7Qp
} finally{ >sq9c/}X
try{ ;k]pq 4E
if(ps!=null) { IK);BN2<L
ps.clearParameters(); {]]I4a
ps.close(); 0kfw8Lon
ps=null; [U0c
} 9mZ1 a6,x
}catch(SQLException e){} f[D#QC
DBUtils.closeConnection(conn); X)+N>8o?N
} ^xrR3m*d
} i`;I"oY4
public long getLast(){ duCm+4,.
return lastExecuteTime; :1Cc~+]w(u
} OMU#Sx!6
public void run(){ lLv0lf
long now = System.currentTimeMillis(); {[+gM?
if ((now - lastExecuteTime) > executeSep) { LtBH4A
//System.out.print("lastExecuteTime:"+lastExecuteTime); HS7!O
//System.out.print(" now:"+now+"\n"); EC0auB7G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +FR"Gt$g
lastExecuteTime=now; Kkm7L-
executeUpdate(); I(e>ff
} ';%g^!lM
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else{ WjB[e>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); qMkP/BjV
} +nuQC{^>
} V<7Gd8rDMM
} A
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 -~g3?!+Hb
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类写好了,下面是在JSP中如下调用。 2StpcAlU}
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<% x$E
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CountBean cb=new CountBean(); pFuQ!7Uk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $O#h4L_
CountCache.add(cb); Y~6pJNR
out.print(CountCache.list.size()+"<br>"); gE&f}M-
CountControl c=new CountControl(); E:ytdaiT
c.run(); `}bUf epMJ
out.print(CountCache.list.size()+"<br>"); ?l/rg6mbI'
%>