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: s\.r3U&6
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CountBean.java +46& Zb35
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/* 5P*jGOg .
* CountData.java D[T\_3W
* )~)T[S
* Created on 2007年1月1日, 下午4:44 J;fbE8x
* oKRI2ni$j9
* To change this template, choose Tools | Options and locate the template under >>=zkPy
* the Source Creation and Management node. Right-click the template and choose x>i =
* Open. You can then make changes to the template in the Source Editor. =j_4!^
*/ =
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package com.tot.count; w&U28"i>
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/** Kj"n
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* SOD3MsAK
* @author R]Fa?uQW
*/ @$b7
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public class CountBean { Ow0~sFz
private String countType; JpQV7}$
int countId; MNfc1I_#
/** Creates a new instance of CountData */ L#V e[
public CountBean() {} ]<},[s
public void setCountType(String countTypes){ 8v)Z/R-
this.countType=countTypes; AfW:'>2
} N,)rrBD
public void setCountId(int countIds){ ylmVmHmc
this.countId=countIds; UuJ gB)
} 8LtkP&Wx
public String getCountType(){ [c>YKN2qa
return countType; voN, u>U
} CwF=@:*d
public int getCountId(){ `)jAdad-s
return countId; f+Bv8 g
} !&8B8jHqA
} 3k+46Wp
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CountCache.java \p iz Vt
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/* ds+0y;vc
* CountCache.java ~RM_c
* a
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* Created on 2007年1月1日, 下午5:01 $8_b[~%2
* |>p?Cm
* To change this template, choose Tools | Options and locate the template under &W y9%
* the Source Creation and Management node. Right-click the template and choose }!vJ+
* Open. You can then make changes to the template in the Source Editor. ma2-66M~j
*/ K30{Fcb< h
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package com.tot.count; cr{f*U6`
import java.util.*; ]+78
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/** Pu]Pp`SP
* oGZ%w4T
* @author z!\)sL/"
*/ 8z"*CJ@
public class CountCache { NHzhGg]
public static LinkedList list=new LinkedList(); ,dk!hm u
/** Creates a new instance of CountCache */ a^GJR]]
{
public CountCache() {} &Sp2['a!
public static void add(CountBean cb){ "f`{4p0v
if(cb!=null){ arj?U=zy
list.add(cb); F| O
} w>gB&59r
} PeB7Q=d)K1
} odpjEeQC
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CountControl.java _QOZ`st
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/* .q(1
* CountThread.java *U^7MU0
* CrI:TB>/"
* Created on 2007年1月1日, 下午4:57 b$1W>
* 3N 5b3F
* To change this template, choose Tools | Options and locate the template under A^"( VaK
* the Source Creation and Management node. Right-click the template and choose e47N 9&4
* Open. You can then make changes to the template in the Source Editor. pbePxOG
*/ ;sn]Blpq
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package com.tot.count; =6:>C9
import tot.db.DBUtils; EG[Rda
import java.sql.*; jpek=4E
/** f^?k?_~PN
* DNl'}K1W
* @author $UGX vCR
*/ /V@9!
public class CountControl{ 'l*p!=
private static long lastExecuteTime=0;//上次更新时间 gG6j>%y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tjTnFP/=
/** Creates a new instance of CountThread */ {:0TiOP5x
public CountControl() {} ^9*kZV<K
public synchronized void executeUpdate(){ <*55d2
Connection conn=null; i j+)U`
PreparedStatement ps=null; zBTyRL
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try{ TO~Z6NA0
conn = DBUtils.getConnection(); R-V4Ju[:
conn.setAutoCommit(false); .~t.B!rVSB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n6]8W^g
for(int i=0;i<CountCache.list.size();i++){ =7212('F
CountBean cb=(CountBean)CountCache.list.getFirst(); %DR8M\d1~H
CountCache.list.removeFirst(); "MNI_C#{
ps.setInt(1, cb.getCountId()); )D"E]
ps.executeUpdate();⑴ 85GU~.
//ps.addBatch();⑵ c Y(2}Ay
} osdl dS
//int [] counts = ps.executeBatch();⑶ \&Zp/;n
conn.commit(); L6=`x a,
}catch(Exception e){ 7lH3)9G;
e.printStackTrace(); K~ob]I<GiB
} finally{ e;G}T%W
try{ nWz7$O
if(ps!=null) { gJC~$/2
ps.clearParameters(); vQ",rP%
ps.close(); }lP'bu
ps=null; J70r`
} cA8A^Iv:0
}catch(SQLException e){} g<(\# F}/
DBUtils.closeConnection(conn); $4ZjN N@
} J':x]_;
} v%$c_'d
public long getLast(){ aoP=7d|K/
return lastExecuteTime; O=E?m=FR"
} '`nf7b(
public void run(){ a
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long now = System.currentTimeMillis(); x@*!MC#
if ((now - lastExecuteTime) > executeSep) { BDiN*.w5
//System.out.print("lastExecuteTime:"+lastExecuteTime); %;MM+xVVX
//System.out.print(" now:"+now+"\n"); _my!YS5n
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0 F-db
lastExecuteTime=now; xjK@Q1MJ
executeUpdate(); P4{!/&/
} O@-|_N*;K
else{ dp DPSI
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); MlH0
} % db
} e` {F7rd:
} wx[Y2lUh6
//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 # ;3v4P
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类写好了,下面是在JSP中如下调用。 C=,O'U(ep
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<% $3)Z>p
CountBean cb=new CountBean(); +b_o2''
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ,LftQ1*;
CountCache.add(cb); we}G%09L
out.print(CountCache.list.size()+"<br>"); n&\DJzW\#
CountControl c=new CountControl(); !si}m~K!_
c.run(); Tx:S{n7&
out.print(CountCache.list.size()+"<br>"); ;%B:1Z
%>