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: CJu;X[6
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CountBean.java O-y"]Wrv
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/* TTOd0a
* CountData.java D 'u+3
* ]a:kP,
* Created on 2007年1月1日, 下午4:44 a:;*"p[R
* Y7{|EI+@
* To change this template, choose Tools | Options and locate the template under 5 ;|9bWH
* the Source Creation and Management node. Right-click the template and choose 1qQgAhoY
* Open. You can then make changes to the template in the Source Editor. RK'( {1
*/ r{<u\>6X>P
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package com.tot.count; sztnRX_
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/** L>L4%?
* 9J%>2AA
* @author uq%RZF
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*/ V) a6H^l
public class CountBean { 7=<PVJ*/
private String countType; tNUcmiY
int countId; {(tE pr
/** Creates a new instance of CountData */ ;^*^
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public CountBean() {} {:oZ&y)Ac
public void setCountType(String countTypes){ g
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this.countType=countTypes;
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} 9
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public void setCountId(int countIds){ NFa
;
this.countId=countIds; *U8#'Uan
} +f7?L]wzic
public String getCountType(){ ivagS\Q
return countType; zm~~mz A
} C>MoR 3]
public int getCountId(){ 22*t%{(
return countId; I|LS_m
} z$<6;2
} Zq`bd55~
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CountCache.java TY#1Z )%
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/* Y7jD:P
* CountCache.java (la
* txgGL'
* Created on 2007年1月1日, 下午5:01 DRzpV6s
* CTI(Kh+
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose BsRas
* Open. You can then make changes to the template in the Source Editor. (
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*/ \W\6m0-x
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package com.tot.count; .o-j
import java.util.*; Lhc@*_2
/** <.' cCY
* J`8>QMK^5
* @author pts}?
*/
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public class CountCache { zk/!#5JtK
public static LinkedList list=new LinkedList(); $e;!nI;z
/** Creates a new instance of CountCache */ *.+>ur?t
public CountCache() {} -'0AV,{Z
public static void add(CountBean cb){ Mu (Y6
if(cb!=null){ {xykf7zp
list.add(cb); 'w!gQ#De
} yd%\3}-
} |l?ALP_g
} C0fA3y72
SB'YV#--
CountControl.java BJq}1mn*
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/* eHJ7L8#
* CountThread.java TZP{=v<
* mQvKreo~
* Created on 2007年1月1日, 下午4:57 m@Nx`aS?
* N4v)0
* To change this template, choose Tools | Options and locate the template under 2(rZ@Wl
* the Source Creation and Management node. Right-click the template and choose &B2c]GoW
* Open. You can then make changes to the template in the Source Editor. w2,T.3DT
*/ =%u|8Ea*`
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package com.tot.count; q7]WR(e
import tot.db.DBUtils; qB39\j
import java.sql.*; LAKZAi%O0
/** ~ghz%${`
* :^s7#4%6
* @author %~;Q_#CR/K
*/
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public class CountControl{ {UmCn>c
private static long lastExecuteTime=0;//上次更新时间 (p?3#|^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 z\h+6FCD
/** Creates a new instance of CountThread */ #-Rz`Y<&
public CountControl() {} ]p*)
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public synchronized void executeUpdate(){ :fYwFD( 9
Connection conn=null; @r]s9~Lx9
PreparedStatement ps=null; 48ma&f;
try{ =qtoDe
conn = DBUtils.getConnection(); iy#OmI>j
conn.setAutoCommit(false); YJ^ lM\/<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h]MVFn{
for(int i=0;i<CountCache.list.size();i++){ -5cH$]1\
CountBean cb=(CountBean)CountCache.list.getFirst(); cMWO_$
CountCache.list.removeFirst(); qQcC[50
ps.setInt(1, cb.getCountId()); eq+o_R}CS
ps.executeUpdate();⑴ }J?fJ(
//ps.addBatch();⑵ 5Hm!5:ZB
} 9aU:[]w
//int [] counts = ps.executeBatch();⑶ GA_`C"mx
conn.commit(); ?iLd5 Z
}catch(Exception e){ ^0|NmMJ]
e.printStackTrace(); 7
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} finally{ uBTT {GGQ
try{ m3(T0.j0P
if(ps!=null) { N39nJqo>"
ps.clearParameters(); QP[a^5;Tt
ps.close(); u,akEvH~a
ps=null; 8$v7|S6 z
} Doh|G:P]#
}catch(SQLException e){} e8 7-
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DBUtils.closeConnection(conn); 3N"&P@/0x
} rc$!$~|I3Z
} ]jb4Z
public long getLast(){ k2uiu
return lastExecuteTime;
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} `zp2;]W
public void run(){ MH.,s@
long now = System.currentTimeMillis(); bXH^Bm
if ((now - lastExecuteTime) > executeSep) { 0#[f2X62B
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); LZ)m](+M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); oe|e+
lastExecuteTime=now; iHn!KV
executeUpdate(); i"]8Zw_D
} K~8tN,~&
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /plUzy2Yu
} ]kkBgjQbS
} 8KtgSash
} z>33O5U
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 gww^?j#
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类写好了,下面是在JSP中如下调用。 ij(4)=
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<% @7s,|\
CountBean cb=new CountBean(); &U~r}=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !Gp3/<"Wy$
CountCache.add(cb); T#n1@FgC
out.print(CountCache.list.size()+"<br>"); O_Rcd&<mr
CountControl c=new CountControl(); KKjxg7{K
c.run(); E^ok`wfO
out.print(CountCache.list.size()+"<br>"); "q^#39i?
%>