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: ,PW'#U:
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CountBean.java _8J.fT$${
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/* @n /nH?L
* CountData.java :\c ^*K(9
* /Iokf@5
* Created on 2007年1月1日, 下午4:44 k%#EEMh
* 1(R}tRR7 R
* To change this template, choose Tools | Options and locate the template under u4?L 67x
* the Source Creation and Management node. Right-click the template and choose Y\P8v
* Open. You can then make changes to the template in the Source Editor. 'GWN~5
*/ &wawr2)}
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package com.tot.count; _D&598 xx
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/** yx[/|nZDC4
* 9Q.Yl&A
* @author 8kIksy
*/ &
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public class CountBean { I$G['`XX/
private String countType; pah'>dAL
int countId; ~G&dqw/.-U
/** Creates a new instance of CountData */ |YWD8 +
public CountBean() {} _;y9$"A
public void setCountType(String countTypes){ ]s'as9s9
this.countType=countTypes; RbnVL$c
} +\]\[6
public void setCountId(int countIds){ &r/Mi%
this.countId=countIds; g:@#@1rB6
} (5YM?QAd
public String getCountType(){ s ll\g
return countType; h;"4+uw
} Sz`,X0a
public int getCountId(){ 4pF*"B
return countId; 1CZgb
} 'IQ0{&EI
}
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CountCache.java ED gag
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/* kDioD
* CountCache.java !Ai@$tl[S
* (w3YvG.
* Created on 2007年1月1日, 下午5:01 q]-r@yF
* ouQ T
* To change this template, choose Tools | Options and locate the template under p6V0`5@t
* the Source Creation and Management node. Right-click the template and choose Ui W>J
* Open. You can then make changes to the template in the Source Editor. /([kh~a
*/ C1)!f j=
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package com.tot.count; gwMNYMI
import java.util.*; ?fSG'\h>
/** ;A*]l'[-
* Jnov<+
* @author ,f>k%_U}
*/ CD~.z7,LC
public class CountCache { }Sv:`9=
public static LinkedList list=new LinkedList(); :"c*s4
/** Creates a new instance of CountCache */ PJH&
public CountCache() {} yt=3sq
public static void add(CountBean cb){ Et/\xL
if(cb!=null){ !y:vLB#q
list.add(cb); VE{3} S
} vK\%%H
} T;y>>_,
} *|>d
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CountControl.java 9c#+qH
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/* C|).;V&
* CountThread.java ()Y4v
* {/(D$"j(S
* Created on 2007年1月1日, 下午4:57 n%C>E.Tq
* M&@b><B
* To change this template, choose Tools | Options and locate the template under gVv>9W('
* the Source Creation and Management node. Right-click the template and choose uRRQyZ
* Open. You can then make changes to the template in the Source Editor. ^m"u3b4
*/ 8V)^R(\;
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package com.tot.count; NufLzg{
import tot.db.DBUtils; C>$E%=h+_
import java.sql.*; e7(ucE
/** OQT;zqup
* m~Bl*`~M
* @author m&\h4$[kql
*/ S<u-n8bv
public class CountControl{ vj\d A2!~
private static long lastExecuteTime=0;//上次更新时间 2?,EzBeal
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X4t s)>"d
/** Creates a new instance of CountThread */ Q7$.LEioN
public CountControl() {} bKQ"ax>6p
public synchronized void executeUpdate(){ Zh*u(rO
Connection conn=null; Eu-RNrYh#
PreparedStatement ps=null; Y&_&s7z
try{ BV(8y.H
conn = DBUtils.getConnection(); gO,25::")
conn.setAutoCommit(false); t{FlB!jv
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {]_r W/
for(int i=0;i<CountCache.list.size();i++){ DrBUe'RH:M
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); rEv*)W
ps.setInt(1, cb.getCountId()); x-<)\L&
ps.executeUpdate();⑴ ?(m
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//ps.addBatch();⑵ 0=q;@OIf
} w'fT=v)
//int [] counts = ps.executeBatch();⑶ d/|D<Sb[s
conn.commit(); ;VNMD 6H
}catch(Exception e){ .E&z$N
e.printStackTrace(); (_*5oj-
} finally{ f7~9|w&
try{ H_Kj7(=&>
if(ps!=null) { b0A1hb[|
ps.clearParameters(); mBJeqG
ps.close(); )a3J9a;ZS0
ps=null; 5qkH|*Z3
} ;w-qHha
}catch(SQLException e){} M$d%p6Cv
DBUtils.closeConnection(conn); RUUk
f({(
} |vMpXiMxxT
} "zY](P
public long getLast(){ @]c(V%x
return lastExecuteTime; b}wC|\s
} ls `,EFF
public void run(){ ELjK0pE}-
long now = System.currentTimeMillis(); lz0TK)kuC
if ((now - lastExecuteTime) > executeSep) { za9)Q=6FD
//System.out.print("lastExecuteTime:"+lastExecuteTime); d90Z,nex
//System.out.print(" now:"+now+"\n"); wHv]ViNvXE
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); >'5_Y]h4m|
lastExecuteTime=now; *;U'[H3Q
executeUpdate(); <zy,5IlD
} jWO/
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else{ R@yyur~'_(
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Hiv!BV|
} Enq|Y$qm
} a7/-wk
} 0hn-FH-XE
//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 qXW})(
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类写好了,下面是在JSP中如下调用。 tYqs~B3
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<% 1b>C<\
CountBean cb=new CountBean(); &Q=ZwC7#
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )|<_cwz
CountCache.add(cb); C#=bW'C
out.print(CountCache.list.size()+"<br>"); >x@P|\
CountControl c=new CountControl(); m&0"<V!H/B
c.run(); Koln9'tB
out.print(CountCache.list.size()+"<br>"); b2^AP\: k
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