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: 2A|^6#XN'
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CountBean.java bcL>S$B
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/* _?>!Bz
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* CountData.java W7.O(s,32
* 9UTWq7KJ
* Created on 2007年1月1日, 下午4:44 [0.>:wT
* W"Hjn/xSS
* To change this template, choose Tools | Options and locate the template under kwNXKn/
* the Source Creation and Management node. Right-click the template and choose [M_pf2Y
* Open. You can then make changes to the template in the Source Editor. ! P/ ]o
*/ =<fH RX`
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package com.tot.count; ,Hh7'`
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/** 9qD/q?Hh$
* ~ z4T
* @author v:1l2Y)g
*/ 58zs%+F
public class CountBean { ~J?O ~p`&
private String countType; q88p~Ccoa
int countId; h`+Gs{1qw
/** Creates a new instance of CountData */ IrQ8t!
public CountBean() {} ~-x8@ /
public void setCountType(String countTypes){ nP?=uGqCBq
this.countType=countTypes; IIeEe7%#
} }l$M%Ps!a
public void setCountId(int countIds){ 'D%No!+Py
this.countId=countIds; !VpZo*+
} ^y'xcq
public String getCountType(){ 8yz A
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return countType; GDw4=0u-
} o_/C9[:
public int getCountId(){ SF+ ^dPwj
return countId; ka{9{/dz3
} "L@qjSs8
} 3~6F`G
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CountCache.java *E0+!
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/* dvxD{UH
* CountCache.java /-z_"G
* +A8S 6bA[=
* Created on 2007年1月1日, 下午5:01 Le9r7O:
* qyl~*r*
* To change this template, choose Tools | Options and locate the template under ]_I<-}?;
* the Source Creation and Management node. Right-click the template and choose _/ j44q
* Open. You can then make changes to the template in the Source Editor. % \N.m/5
*/ //@_`.
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package com.tot.count; 'j#oMA{0
import java.util.*; g3n^
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/** q_HC68YF,
* Djx9TBZ5
* @author OP
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*/ /'
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public class CountCache { [?Y u3E\
public static LinkedList list=new LinkedList(); asP>(Li
/** Creates a new instance of CountCache */ p9R`hgx
public CountCache() {} ]n?a h
public static void add(CountBean cb){ wJ!
if(cb!=null){ j)Kk:BFFY
list.add(cb); a1ZGMQq!
} G39H@@ *O0
} QnZR
} ^q"p8
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CountControl.java ~cSC-|$^&
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/* o;FjpZ
* CountThread.java +f\tqucI3
* Zm%}AzM
* Created on 2007年1月1日, 下午4:57 \F,?ptu
* ;1S{xd*^N
* To change this template, choose Tools | Options and locate the template under GW'=/
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* the Source Creation and Management node. Right-click the template and choose 6v GcM3M
* Open. You can then make changes to the template in the Source Editor. Gcg`Knr
*/ Xfx(X4$ 9
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package com.tot.count; H:U1#bQQ:
import tot.db.DBUtils; ;G!X?(%+
import java.sql.*; SynxMUlA
/** l1jS2O(
* W#e:r z8=
* @author r&}fn"H!
*/ WP32t@
public class CountControl{ `@ qSDW!b
private static long lastExecuteTime=0;//上次更新时间 ig; ~
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 IK{0Y#c
/** Creates a new instance of CountThread */ /.'1i4Xa1P
public CountControl() {} i3: sV 5
public synchronized void executeUpdate(){ ~J)4 (411
Connection conn=null; JC{}iG6r+
PreparedStatement ps=null; ~FZLA}
try{ PNT.9 *d
conn = DBUtils.getConnection(); w|Zq5|[
conn.setAutoCommit(false); aEXV^5;,pJ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \#tr4g~u
for(int i=0;i<CountCache.list.size();i++){ qfC9 {gu
CountBean cb=(CountBean)CountCache.list.getFirst(); 0J$wX yh
CountCache.list.removeFirst(); 4}580mBc
ps.setInt(1, cb.getCountId()); f:7Y
ps.executeUpdate();⑴ ++,mM7a
//ps.addBatch();⑵ Ze WHSU
} TuIeaH% x
//int [] counts = ps.executeBatch();⑶ 8i-?\VZD
conn.commit(); TW3:Y\ p
}catch(Exception e){ wgLS9.
e.printStackTrace(); ./#K@V1
} finally{ Y+/ofk"
try{ Ea\a:
if(ps!=null) { W7(OrA!
ps.clearParameters(); ddnWr"_
ps.close(); }C"#b\A2
ps=null; ct~lt'L\
} )yJe h
}catch(SQLException e){} J)(]cW.
DBUtils.closeConnection(conn); iCAd7=o
} ih+kh7J-
} b4%IyJr
public long getLast(){ #l;Ekjfz
return lastExecuteTime; I_pA)P*Q(6
} z@~1e]%
public void run(){ <]wN/B-8J
long now = System.currentTimeMillis(); }'H Da M
if ((now - lastExecuteTime) > executeSep) { Q2rZMK
//System.out.print("lastExecuteTime:"+lastExecuteTime); m
7 Fz&bN
//System.out.print(" now:"+now+"\n"); )QBsyN<x6
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); *tRJ=
lastExecuteTime=now; apY m,_
executeUpdate(); u8o7J(aQsR
} 9\Xl3j!
else{ q<hN\kBs
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sE/9~L
} Pv1psKu
} vZ]gb$
} {B\.8)&8
//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 r`<evwIe
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类写好了,下面是在JSP中如下调用。 pQVi&( M
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<% /%xK-z,V
CountBean cb=new CountBean(); RtqW!ZZ:H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B.Xm*adBT
CountCache.add(cb); ,{oP`4\Lm
out.print(CountCache.list.size()+"<br>"); W_sDF; JP
CountControl c=new CountControl(); )@K|Co
c.run(); Z@I%ppd
out.print(CountCache.list.size()+"<br>"); -3 W4
%>