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: X:5*LB\/v
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CountBean.java @P>@;S
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/* j!/(9*\
* CountData.java Qzv_|U
* +Oa1FvoEA
* Created on 2007年1月1日, 下午4:44 7Ll(,i<,C
* ),eiJblH
* To change this template, choose Tools | Options and locate the template under $?YkgK
* the Source Creation and Management node. Right-click the template and choose oR }
* Open. You can then make changes to the template in the Source Editor. 2}AV_]]
*/ XDF",N)
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package com.tot.count; @lI/g
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/** MDpXth7
* "%Ak[04'
* @author %JZIg!
*/ 1C{~!=6#
public class CountBean { 7E'C o|
private String countType; E {MSi"
int countId; \<%a`IA!*
/** Creates a new instance of CountData */ [+GG Wo
public CountBean() {} &!=3Fbn
public void setCountType(String countTypes){ g;pymz
this.countType=countTypes; w pvaTHo
} )mU)7@!
public void setCountId(int countIds){ ?/~1z*XUW
this.countId=countIds; _)Ms9RN
} D~Su822
public String getCountType(){ |(fWT}tg
return countType; ]_h"2|
} h4CB1K
public int getCountId(){ aw`mB,5U
return countId; 2iu;7/
} <fxYTd<#D[
} ^]kDYhe*Y
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CountCache.java q0}LfXql8
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/* 6S(3tvUr
* CountCache.java UcZ3v]$I
* 'D
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* Created on 2007年1月1日, 下午5:01 V}*b^<2o5
* bm^ou#]|
* To change this template, choose Tools | Options and locate the template under 8LL);"$
* the Source Creation and Management node. Right-click the template and choose wRKGJ
* Open. You can then make changes to the template in the Source Editor. +W}f0@#)<
*/ l\eq/yg_
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package com.tot.count; lL?;?V~
import java.util.*; #q-t!C%E
/** [|3
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* v1:5r
* @author I;7VX5X
*/ h*Ej}_
public class CountCache { SWu=n1J.?H
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ Y9C] -zEv
public CountCache() {} zr,jaR;
public static void add(CountBean cb){ Cpr}*A
if(cb!=null){ p|Ln;aYc
list.add(cb); &EMm<(.]a
} sU>*S$X8
} </eh^<_~
} Z?~7#F~Z`
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CountControl.java vi'K|[!?
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/* UuN(+&oD-
* CountThread.java umi#Se3&
* J[9jNCq|
* Created on 2007年1月1日, 下午4:57 OAv/P|n=
* N%0Z>
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* To change this template, choose Tools | Options and locate the template under 9i"3R0HN
* the Source Creation and Management node. Right-click the template and choose >0> M@s
* Open. You can then make changes to the template in the Source Editor. -n6C~Yx
*/ rh+OgKi
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package com.tot.count; d{0>R{uac
import tot.db.DBUtils; C'{Z?M>
import java.sql.*; D%Wr/6X
/** 7Kn=[2J5k'
* ' _N >
* @author )/BKN` ,
*/ 1vobfZ-w9
public class CountControl{ Y}0 - &
private static long lastExecuteTime=0;//上次更新时间 X%;,r
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;m\E9ple
/** Creates a new instance of CountThread */ NY_Oo!)3
public CountControl() {} {r Gx*<e
public synchronized void executeUpdate(){ xH92=t-w
Connection conn=null; @x)z" )>
PreparedStatement ps=null; :`_wy-}V
try{ <)M?qkjb
conn = DBUtils.getConnection(); ]^s4NXf+
conn.setAutoCommit(false); p0-\G6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qoEOM%dAqV
for(int i=0;i<CountCache.list.size();i++){ (A1 !)c
CountBean cb=(CountBean)CountCache.list.getFirst(); }ts?ZR^V,
CountCache.list.removeFirst(); 7UMsKE-
ps.setInt(1, cb.getCountId()); iJ~pX\FKO
ps.executeUpdate();⑴ GU=h2LSi]
//ps.addBatch();⑵ 1aSuRa
} oI^iL\\2h
//int [] counts = ps.executeBatch();⑶ t hS#fO4]d
conn.commit(); *G=n${'
}catch(Exception e){ Y#uf 2>J
e.printStackTrace(); *rA!`e*
} finally{ sO6+L
#!
try{ 4pF%G
if(ps!=null) { 7bTs+C_;7
ps.clearParameters(); iK)w3S}k1y
ps.close(); ZV&=B%J bs
ps=null; r&^4L
} ~=}56yxl[
}catch(SQLException e){} '?#e$<uS-
DBUtils.closeConnection(conn); 2f4 *r^
} >b/Yg:t
} !]W6i]p
public long getLast(){ (!;4Y82#
return lastExecuteTime; nPKf~|\1{
} bvAO(`
public void run(){ M[N|HsI8?
long now = System.currentTimeMillis(); dlyE2MiL:
if ((now - lastExecuteTime) > executeSep) { u'}DG#@ -
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ff|?<\x0}A
//System.out.print(" now:"+now+"\n"); iHTxD1D+H
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); eqXW|,zUm
lastExecuteTime=now; a
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executeUpdate(); o6'`W2P
} @UD6qA
else{ xJ,V!N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); TMGZHOAt
} Dj?95Z,r
} ,VbP$1t
} ,~c:P>v=
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 D_'Zucq
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类写好了,下面是在JSP中如下调用。 @aI`ru+a
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<% Yr"G)i~"Y
CountBean cb=new CountBean(); 9Lv`3J^~
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7
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CountCache.add(cb); b5KX` r
out.print(CountCache.list.size()+"<br>"); GT`:3L
CountControl c=new CountControl(); }KJ/WyYW
c.run(); Hz28L$
out.print(CountCache.list.size()+"<br>"); N9_9{M{
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