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: ,1JQjsR
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CountBean.java /d Ua
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/* Nlwt}7
* CountData.java Z("N
*`VP;
* CWYOzqf
* Created on 2007年1月1日, 下午4:44 qt"6~r!
*
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* To change this template, choose Tools | Options and locate the template under 7M5HvG#w%
* the Source Creation and Management node. Right-click the template and choose a\Gd;C ^`
* Open. You can then make changes to the template in the Source Editor. Nl%5OBm
*/ Ukf:m&G
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package com.tot.count; )"M;7W?R0
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/** j>
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* yT7{,Z7t
* @author BePb8
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*/ OPqhdqo
public class CountBean { ]iFW>N*a
private String countType; XbFo#Pwk
int countId; @ptrF
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/** Creates a new instance of CountData */ [O!/hppN
public CountBean() {} ?6x&A t
public void setCountType(String countTypes){ V|HO*HiB3
this.countType=countTypes; }NdLd!
} |o(te
public void setCountId(int countIds){ f.oY:3h:
this.countId=countIds; xUa9>=JU{
} UCFFF%
public String getCountType(){ ';D>Z?l
return countType; l^}5PHLd
} vMn$lT@
public int getCountId(){ SNSoV3|k-
return countId; 00y(E@~
} T<yfpUzX
} !/|B4Yv
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CountCache.java wGIRRM !b
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/* 6!*zgA5M'
* CountCache.java
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* Iq6EoDoq
* Created on 2007年1月1日, 下午5:01 Dsv2p~
* z\K%
* To change this template, choose Tools | Options and locate the template under P# 8lO%;
* the Source Creation and Management node. Right-click the template and choose ?hIDyM
* Open. You can then make changes to the template in the Source Editor. s`.J!^u`
*/ <dBz]W
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package com.tot.count; 1 un!
import java.util.*; 2@HmZ!|Q
/** O]F(vHK\
* +x4*T
* @author 4ISIg\:c*
*/ pXh`o20I
public class CountCache { I!K-*
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public static LinkedList list=new LinkedList(); o4z|XhLr
/** Creates a new instance of CountCache */ T`<Tj?:^&
public CountCache() {} \lDh"
public static void add(CountBean cb){ 6ZjY-)h
if(cb!=null){ I,&
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list.add(cb); Jiru~Vo+
} b#t5Dve
} XQ}7.u!
} NPa4I7`A
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CountControl.java Eb29tq
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/* ^hT2ed +
* CountThread.java V$u:5"qu0
* I_`NjJ;61
* Created on 2007年1月1日, 下午4:57 /@DJf\`vM
* YuzVh9jTI
* To change this template, choose Tools | Options and locate the template under >I&s%4
* the Source Creation and Management node. Right-click the template and choose 8Vt'X2
* Open. You can then make changes to the template in the Source Editor. {\LLiU}MJC
*/ ?\X9Ei
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package com.tot.count; jrttWT
import tot.db.DBUtils; +#X+QG
import java.sql.*; 9]/:B8k
/** s,Fts3+
* $V/Ke
* @author b 1."mT!p
*/ G2|G}#E
public class CountControl{ , BZ(-M
private static long lastExecuteTime=0;//上次更新时间 0+e0<'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2:yXeSeA
/** Creates a new instance of CountThread */ X1V~.kvt)
public CountControl() {} hOdU%
public synchronized void executeUpdate(){ 2G3Hi;q18
Connection conn=null; ^R7X!tOq4
PreparedStatement ps=null; YXdo&'Q<qX
try{ ?D_}',Wx
conn = DBUtils.getConnection(); :."+&gb
conn.setAutoCommit(false); yy3`E}vX7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yaHkWkl
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for(int i=0;i<CountCache.list.size();i++){ qB`%+<)C
CountBean cb=(CountBean)CountCache.list.getFirst(); %\!0*(8
CountCache.list.removeFirst(); 2%H_%Zu9
ps.setInt(1, cb.getCountId()); jOK!k
ps.executeUpdate();⑴ sY]pszjT
//ps.addBatch();⑵ [~n|R Oo
} Sj8fo^K50
//int [] counts = ps.executeBatch();⑶ aan(69=jz
conn.commit(); p}X *HJq$
}catch(Exception e){ 5,Co(K
e.printStackTrace(); jz\>VYi(7
} finally{ 6hXh;-U
try{ 6_g6e2F
if(ps!=null) { {e., $'#
ps.clearParameters(); `sd
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ps.close(); V*@&<x"E
ps=null; ZHj7^y@P
} vEt+^3=
}catch(SQLException e){} r& :v(
DBUtils.closeConnection(conn); *ck'vV'@
} XuU>.T$] c
} xa{.hp?
public long getLast(){ lhBAT%U\
return lastExecuteTime; D>-Pv-f/
} vrvi]
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public void run(){ a5w E{K
long now = System.currentTimeMillis(); kpQN>XV#
if ((now - lastExecuteTime) > executeSep) { OE}c$!@
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,wyEo>>4)
//System.out.print(" now:"+now+"\n"); wDBU+Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5T'viG}%
lastExecuteTime=now; `+UBl\j
executeUpdate(); cf%2A1I2W
} zYftgH_o
else{ +)_DaL
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :8?l=B9("g
} /6y;fx
} V[7D4r.j
} A\.{(,;kp
//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 x
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类写好了,下面是在JSP中如下调用。 IhK%.B{dZ
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<% Kzwe36O;?
CountBean cb=new CountBean(); H8Z|gq1r
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); &nY#GHB
CountCache.add(cb); O}6*9Xy
out.print(CountCache.list.size()+"<br>"); ydE}.0zN
CountControl c=new CountControl(); F C=N}5u
c.run(); 9*r l7
out.print(CountCache.list.size()+"<br>"); e8z?) 4T
%>