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: 4r&f%caU
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CountBean.java ~}'F887 f
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/* A_R!uRD8-
* CountData.java ys8Q.oBv_`
* )&,{?$ .
* Created on 2007年1月1日, 下午4:44 Qs9OC9X1
* &eQJfc\a
* To change this template, choose Tools | Options and locate the template under O("Uq../3
* the Source Creation and Management node. Right-click the template and choose aC!EWgwW[
* Open. You can then make changes to the template in the Source Editor. .WX,Nd3@
*/ ^:KO_{3E
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package com.tot.count; c?E{fD"Fc3
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/** 0fArF*
* oehaQ#e
* @author z wk.bf>m
*/ Y3Oz'%B
public class CountBean { D#Kuo$
private String countType; ^zr^ N?a
int countId; `VT>M@i/
/** Creates a new instance of CountData */ tU@zhGb
public CountBean() {} "35A/V
public void setCountType(String countTypes){ ]*N1t>fb
this.countType=countTypes; Udgqkl
} ,SUT~oETP
public void setCountId(int countIds){ taWqSq!
this.countId=countIds; I:l01W;
} +v7) 1y
public String getCountType(){ ~F!,PM/
return countType; e,0-)?5R
} O
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public int getCountId(){ F #`=oM$5
return countId; fjG&`m#"
} wTc)S6%7
} j:,9%tg
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CountCache.java rD
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/* Yh<WA>=
* CountCache.java -_N)E ))G
* ;9a 6pz<
* Created on 2007年1月1日, 下午5:01 `]i
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* %*}Y6tl '|
* To change this template, choose Tools | Options and locate the template under "ju'UOcS/
* the Source Creation and Management node. Right-click the template and choose cU.9}-)
* Open. You can then make changes to the template in the Source Editor. "i^
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*/ ravyiOL
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package com.tot.count; !&^gaUa{
import java.util.*; A7Po 3n%Q
/** :-T*gqj|
* -NJ!g/ >mM
* @author 7[pBUDA
*/ neZ.`"LV
public class CountCache { u]*0;-tz
public static LinkedList list=new LinkedList(); % Zjdl
/** Creates a new instance of CountCache */ <0P5 o|
public CountCache() {} 8\.b4FNJ
public static void add(CountBean cb){ Yk!/ow@.
if(cb!=null){ 0RFRbi@n(
list.add(cb); nh+l78
} Z4b||
} }<a^</s
} Smw QET<H
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CountControl.java #W>QY Tp
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/* +Vb8f["+-
* CountThread.java ^D%Za'
* zP\7S}p7%
* Created on 2007年1月1日, 下午4:57 R%Y`=pK>}
* GLMm(
* To change this template, choose Tools | Options and locate the template under avQJPB)}Sb
* the Source Creation and Management node. Right-click the template and choose ^x>Qf(b
* Open. You can then make changes to the template in the Source Editor. Z @ dC+0[=
*/ , t5 '
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package com.tot.count; 4<dcB@v
import tot.db.DBUtils; *cuuzi&
import java.sql.*; E
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/** FzQTDu9
* 'k0[rDFc#3
* @author Pz*_)N}j >
*/ m0n)dje
public class CountControl{ l7H
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private static long lastExecuteTime=0;//上次更新时间 -a,-J]d0+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <EO$]>;0
/** Creates a new instance of CountThread */ dO> VwP
public CountControl() {} q[q?hQ/b
public synchronized void executeUpdate(){ B%CTOi
Connection conn=null; CAq/K?:8
PreparedStatement ps=null; `.jzuX
try{ b//B8^Eong
conn = DBUtils.getConnection(); x+8_4>,>Y7
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Ysq'2
for(int i=0;i<CountCache.list.size();i++){ }o4N<%/+
CountBean cb=(CountBean)CountCache.list.getFirst(); v{zMO:3
CountCache.list.removeFirst(); }/tf>?c
ps.setInt(1, cb.getCountId()); #'D"
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ps.executeUpdate();⑴ eV:9y
//ps.addBatch();⑵ C?v[Z]t
} ZYU=\
//int [] counts = ps.executeBatch();⑶ `*", <
conn.commit(); 6tHO!`}1
}catch(Exception e){ M5nWVK7c
e.printStackTrace(); )c n+1R
} finally{ Qd}m`YW-f$
try{ )a9 ]US^
if(ps!=null) { >(uZtYM\j
ps.clearParameters(); y&}E~5O
ps.close(); *4+3ObA
ps=null; X[
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} &qpr*17T
}catch(SQLException e){} 1tTgP+
DBUtils.closeConnection(conn); (~CLn;'
} AjcX N
} MYJg8 '[j
public long getLast(){ X[`bMa7IB(
return lastExecuteTime; b2aF 'y/
} EVp,Q"V]
public void run(){ 3bk|<7tl
long now = System.currentTimeMillis(); )[0T16
if ((now - lastExecuteTime) > executeSep) { f` =CpO*
//System.out.print("lastExecuteTime:"+lastExecuteTime); }bY;q-
//System.out.print(" now:"+now+"\n"); Tc8un.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); kB?al#`
lastExecuteTime=now; ]f+ csB
executeUpdate(); p' M%XBu
} Ox#\M0Wn$3
else{ 3_~cMlr3T.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); yjfat&$
} Eskb9^A
} 'RRmIx2X
} -~?J+o+Pr"
//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 l @^3Exwt
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类写好了,下面是在JSP中如下调用。 dJT]/g
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<% eF[63zx5*
CountBean cb=new CountBean(); TIp:FW[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); f$NM M
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CountCache.add(cb); ?5_7;Ha
out.print(CountCache.list.size()+"<br>"); kOIt(e
CountControl c=new CountControl(); _g1b{$
c.run(); r.4LU
out.print(CountCache.list.size()+"<br>"); !r#?C9Sq
%>