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: Y9w^F_relL
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CountBean.java U;qGUqI
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/* {gkY:$xnrG
* CountData.java 9sId2py]W
* 8-_\Q2vG
* Created on 2007年1月1日, 下午4:44 r9vO(m~
* -ld1o+'`v!
* To change this template, choose Tools | Options and locate the template under JNL9t0x
* the Source Creation and Management node. Right-click the template and choose #Aver]eK
* Open. You can then make changes to the template in the Source Editor. H[e=^JuD
*/ `^G?+p2E
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package com.tot.count; {Y6;/".DM
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/** "oLY";0(=
* AEw~LF2w
* @author T4e-QEH
*/ /4M~ 6LT`
public class CountBean { +\yQZ{4'@
private String countType; .dQEr~f #}
int countId; ZDl6F`
/** Creates a new instance of CountData */ p| &9#?t4A
public CountBean() {} aBblP8)8;K
public void setCountType(String countTypes){ 7O]$2
this.countType=countTypes; 0Q)m>oL.
}
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public void setCountId(int countIds){ qi]"`\
this.countId=countIds; ;X}!;S%K
}
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public String getCountType(){ 6%\&m|S
return countType; C8bBOC(
} lWRRB&8
public int getCountId(){ F4|U\,g
return countId; C4.g}q
} sqE? U*8.-
} 0<$t9:dq
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CountCache.java ~}@cSv'(1
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/* *,y .%`o
* CountCache.java 7@u:F?c
* 'g#EBy
* Created on 2007年1月1日, 下午5:01 7|Bg--G1
* 6_zyPh
* 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 %1UdG6&J_
* Open. You can then make changes to the template in the Source Editor. tGVC"a
*/ %kXg|9Bx!
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package com.tot.count; 5m\T~[`%
import java.util.*; +m]Kj3-z@
/** ;+NU;f/WM
* fZNWJo# `.
* @author NzAMX+L
*/ VPI;{0kh
public class CountCache { 0~GtK8^B
public static LinkedList list=new LinkedList(); Sft+Gb6
/** Creates a new instance of CountCache */ +/|t8z FWs
public CountCache() {} V'm4DR#M
public static void add(CountBean cb){ Bf+7;4-
if(cb!=null){ svj0;x5
list.add(cb); Ns#R`WG)
} UWIw/(Mv/]
} s F!nSr
} Jd-u?
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CountControl.java :@c\a99Kx
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/*
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* CountThread.java xwe^_7
* 01&J7A2
* Created on 2007年1月1日, 下午4:57 )2dTgvy
* >[&Zs3>
* To change this template, choose Tools | Options and locate the template under 0$1-5XY9
* the Source Creation and Management node. Right-click the template and choose dHJ#xmE!pP
* Open. You can then make changes to the template in the Source Editor. *)0-N!N#)
*/ =ec"G2$?"
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package com.tot.count; W, -fnJk
import tot.db.DBUtils; TZ>_N;jTZ
import java.sql.*; xu(N'l.7&
/** M9dOLM.
* U_l#lGA(H
* @author Ce-D^9kC
*/ @p$$BUb
public class CountControl{ v#`7,::
private static long lastExecuteTime=0;//上次更新时间 n04lTME
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l
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/** Creates a new instance of CountThread */ M~"93 Q`f^
public CountControl() {} z]33_[G1U
public synchronized void executeUpdate(){ 1_V',0|`>
Connection conn=null; JV_V2L1Ut
PreparedStatement ps=null; nhb: y
try{ JoIh2P D
conn = DBUtils.getConnection(); KoF_G[m
conn.setAutoCommit(false); L.R4 iN
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^f_4w|u,+
for(int i=0;i<CountCache.list.size();i++){ }Gi4`Es
CountBean cb=(CountBean)CountCache.list.getFirst(); #}|g8gh
CountCache.list.removeFirst(); V0/O
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ps.setInt(1, cb.getCountId()); x!^u$5c
ps.executeUpdate();⑴ CTh!|mG
//ps.addBatch();⑵ ReZ&SNJ
} ZgH(,g,TU
//int [] counts = ps.executeBatch();⑶ s$PPJJT{b
conn.commit(); XPd@>2
}catch(Exception e){ WB(Gx_o3
e.printStackTrace(); \95O
} finally{ w$j!89@)
try{ "79"SSfOc
if(ps!=null) { ML-?#jNa<
ps.clearParameters(); SU80i`
ps.close(); +u|p<z
ps=null; SZ3UR
} z(JDLd
}catch(SQLException e){} p0Ra`*f
DBUtils.closeConnection(conn); p"k[ac{
} tShyG!b
} ,bnrVa(I
public long getLast(){ Uh=@8v
return lastExecuteTime; wr{ [4$O
} K! e51P
public void run(){ ,'c?^ $J|z
long now = System.currentTimeMillis(); iciw 54;4
if ((now - lastExecuteTime) > executeSep) { %FSY}65
//System.out.print("lastExecuteTime:"+lastExecuteTime); -ttH{SslM
//System.out.print(" now:"+now+"\n"); 9:1[4o)~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~
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lastExecuteTime=now; jGaI6G'N
executeUpdate(); #V#sg}IhM?
} nr>Os@\BU
else{ @?YO_</
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); u>-pgu
} 2B`#c}PP
} 6&KvT2?tA`
} j]5mzz~
//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 1$1[6
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类写好了,下面是在JSP中如下调用。 Q( g&/O
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<% 71(C@/J
CountBean cb=new CountBean(); ?@LqrKj11
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); GiGXV @dq
CountCache.add(cb); . ]D7Il
out.print(CountCache.list.size()+"<br>"); #Rx|oSc}
CountControl c=new CountControl();
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c.run(); q[Ed6FM$~
out.print(CountCache.list.size()+"<br>"); *Z:'jV<
%>