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: =_`cY^ib+
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CountBean.java S|T*-?|
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/* je=XZ's,i~
* CountData.java me@EKspX
* ]wV_xZ)l^A
* Created on 2007年1月1日, 下午4:44 pY(S]i
* [ejl #'*5
* To change this template, choose Tools | Options and locate the template under BV]$=
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* the Source Creation and Management node. Right-click the template and choose wQ\bGBks
* Open. You can then make changes to the template in the Source Editor. =[`gfw
*/ - _BjzA|
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package com.tot.count; ~{[,0,lWU
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/** BzI(
* A7TV-eWG
* @author %(g!,!l)
*/ JO\KTWtjO
public class CountBean { 5} 1qo7;
private String countType; 5>~q4t)6z}
int countId; ^c:I]_Ww
/** Creates a new instance of CountData */ ;ZR^9%+y9
public CountBean() {} 0]l9x}
public void setCountType(String countTypes){ BDPF>lPf<
this.countType=countTypes; vPx#TXY=b}
} ;f2<vp;U
public void setCountId(int countIds){ #v:A-u
this.countId=countIds; N~9zQ
} %QX"oRMn0
public String getCountType(){ hr/|Fn+kA
return countType; _kQOax{c/
} >`+lEob
public int getCountId(){ ou[Wz{
return countId; NucLf6
} Xvn \~Vr
} 3y-P-NI~=
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CountCache.java Z4tc3e
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/* 1Ewg_/R
* CountCache.java ~}s0~j ~
* );fPir?+
* Created on 2007年1月1日, 下午5:01 Hu$JCB-%
* RH&}'4JE:
* To change this template, choose Tools | Options and locate the template under BmCBC,j<v>
* the Source Creation and Management node. Right-click the template and choose qim|=
* Open. You can then make changes to the template in the Source Editor. 5S&^mj-9
*/ I9kBe}g3
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package com.tot.count; SW=%>XKkh
import java.util.*; yb'v*B]
/** RBOhV/f
* kk+:y{0V
* @author [I%'\CI;
*/ HG[gJ7
public class CountCache { txy'7t
public static LinkedList list=new LinkedList(); F1&7m
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/** Creates a new instance of CountCache */ #L xfE<^
public CountCache() {} $
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public static void add(CountBean cb){ /{nZI_v#
if(cb!=null){ r }Nq"s<
list.add(cb); s:Z1
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} mp17d$R-
} 3H,>[&d
} n|!O .+\b
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CountControl.java fh@/fd
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/* >2;KPV0H
* CountThread.java G>W:3y
* Q?-u J1J
* Created on 2007年1月1日, 下午4:57 |~YhN'OJ
* 6G>bZ+
* To change this template, choose Tools | Options and locate the template under 6>-Gi
* the Source Creation and Management node. Right-click the template and choose +g8uV hC
* Open. You can then make changes to the template in the Source Editor. 8'Q1'yc
*/ 1xMD
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package com.tot.count; j'&a)-Wx_
import tot.db.DBUtils; bv'Z~@<c
import java.sql.*; sys;Rz2
/** mNr<=Z%b
* /n#t.XJY*
* @author K]dX5vJw'
*/ ceNJXK
public class CountControl{ `/eh
private static long lastExecuteTime=0;//上次更新时间 StM)lVeF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ DP4l
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public CountControl() {} }t5pz[zl
public synchronized void executeUpdate(){ 'K3%@,O
Connection conn=null; B~/ejC!
PreparedStatement ps=null; }o9(Q8
try{ [NguQ]B.
conn = DBUtils.getConnection(); N;XJMk_ H
conn.setAutoCommit(false); |NaEXzo|qY
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); +/2:
for(int i=0;i<CountCache.list.size();i++){ &6@e9ff0
CountBean cb=(CountBean)CountCache.list.getFirst(); _D."KU|
CountCache.list.removeFirst(); ;#6j9M0
ps.setInt(1, cb.getCountId()); w0$l3^}z
ps.executeUpdate();⑴ v9vY#W
//ps.addBatch();⑵ u"M^qRhD
} -vBk,;^>
//int [] counts = ps.executeBatch();⑶ ({p@Ay
conn.commit(); Op:7EdT#
}catch(Exception e){ ED
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e.printStackTrace(); d)jX%Z$LC
} finally{ +0FmeM&`h_
try{ 8:4`q9
if(ps!=null) { px.]m-
ps.clearParameters(); aFwfF^\(|,
ps.close(); @)m+b;
ps=null; Q-Rt
} )z2hyGX
}catch(SQLException e){} [bJAh ` I
DBUtils.closeConnection(conn); {t&+abY
} 1dX)l
} kR|(hA,$N
public long getLast(){ qf6}\0
return lastExecuteTime; SZ"^>}zl=
} Q5qQ%cu
public void run(){ KoO\<_@";
long now = System.currentTimeMillis(); 3?oj46gP
if ((now - lastExecuteTime) > executeSep) { XW9
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//System.out.print("lastExecuteTime:"+lastExecuteTime); y5bELWA
//System.out.print(" now:"+now+"\n"); jYJfo<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $)Pmr1==
lastExecuteTime=now; *`.4M)Ym~
executeUpdate(); LjA>H>8%[
} &y=~:1&f
else{ pM'AhzS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Og3bV_,"
} (_O_zu8_
} 9:jZ3U
} cE0Kvqe`
//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 Ok2>%e
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类写好了,下面是在JSP中如下调用。 *FEY"W+bY
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<% 2d Px s:8&
CountBean cb=new CountBean(); "Crm\UI6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dLI`\e<r&[
CountCache.add(cb); bAqaf#}e
out.print(CountCache.list.size()+"<br>"); iv62Fs'
CountControl c=new CountControl(); l<#*[TJ
c.run(); Gr?[s'Ze
out.print(CountCache.list.size()+"<br>"); (~FLG I
%>