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: SLd9-N}T
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CountBean.java gY=+G6;=<
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/* N)z]
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* CountData.java Q([g1?F9*
* v#IZSBvuQK
* Created on 2007年1月1日, 下午4:44 oU 8o;zk0
* HoM8V"8B
* To change this template, choose Tools | Options and locate the template under VxAR,a1+n
* the Source Creation and Management node. Right-click the template and choose }Ty_} 6a5
* Open. You can then make changes to the template in the Source Editor. DNM~/Oo
*/ 1G8t=IA%D
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package com.tot.count; eP3 itrH(
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/** :TWHmxch
* tX}Fb0y
* @author `+@%l*TQ
*/ [c6_6q As
public class CountBean { }KkH7XksF
private String countType; F{<rIR
int countId; }@A~a`9g
/** Creates a new instance of CountData */ 6Ue6b$xE
public CountBean() {} t!Av[K
public void setCountType(String countTypes){ X]CaWxM
this.countType=countTypes; d}415 XA
} /L[:C=u
public void setCountId(int countIds){ }`^<ZNkb/
this.countId=countIds; ` }Hnj*
} MN)<Tr2f
public String getCountType(){ mKq9mA"(E
return countType; veE8
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} 7,LT4wYH
public int getCountId(){ Z#W`0G>'
return countId; L,X6L @Q
} I3aEg
} +~/zCJ;F
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CountCache.java pK1(AV'L
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/* g-(xuR^*
* CountCache.java G6Fg<g9:
* @fYA{-ZC
* Created on 2007年1月1日, 下午5:01 +l3
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* EGMcU|yL
* To change this template, choose Tools | Options and locate the template under Yc5$915
* the Source Creation and Management node. Right-click the template and choose X:g5>is|
* Open. You can then make changes to the template in the Source Editor. y.oJzU[p%
*/ I2l'y8)d
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package com.tot.count; {k]VT4/
import java.util.*; `RzM)ILl
/** \1B*iW
* SoY&R=
* @author P?uKDON
*/ V+K.'
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public class CountCache { YvHn~gNPhs
public static LinkedList list=new LinkedList(); +yea}uUE
/** Creates a new instance of CountCache */ Rx<pV_|H,
public CountCache() {} ?x/L"h&Kp
public static void add(CountBean cb){ ]ogy`O >
if(cb!=null){ BR%: `uiQ<
list.add(cb); (c_hX(
} p]g/iLDZ
} 2I4P":q
} 1-[{4{R
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CountControl.java xX>448=
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/* LOYv%9$0*p
* CountThread.java jH G(d$h
* tE>:kx0*3
* Created on 2007年1月1日, 下午4:57 J8D-a!
* +[7u>RJ
* To change this template, choose Tools | Options and locate the template under K^vMIo h
* the Source Creation and Management node. Right-click the template and choose J\0YL\jw1K
* Open. You can then make changes to the template in the Source Editor. !%(B2J
*/ ^b.J z}
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package com.tot.count; TPzoU"
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import tot.db.DBUtils; v>P){VT
import java.sql.*; ?d%}K76V<
/** 1|89-Ii]
* 5~?
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* @author xMh&C{q
*/ cS[`1y,\3
public class CountControl{ n(+:l'#HJ
private static long lastExecuteTime=0;//上次更新时间 pVY.&XBZ$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 5VcYdu3
/** Creates a new instance of CountThread */ #,;k>2j0
public CountControl() {} ouI0"R&@
public synchronized void executeUpdate(){ ]_,~q@r$
Connection conn=null; *]=)mM#
PreparedStatement ps=null; m
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try{ _B[(/wY
conn = DBUtils.getConnection(); yiU dUw/
conn.setAutoCommit(false); 32Z4&~I
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); dA~6{*)
for(int i=0;i<CountCache.list.size();i++){ U#P#YpD;==
CountBean cb=(CountBean)CountCache.list.getFirst(); y%y#Pb|
CountCache.list.removeFirst(); ij),DbWd
ps.setInt(1, cb.getCountId()); G#*;3X$
ps.executeUpdate();⑴ 6bn-NY:i
//ps.addBatch();⑵ x1et,&,
} v]!7=>/2
//int [] counts = ps.executeBatch();⑶ G#C)]4[n
conn.commit(); hU{%x#8}lK
}catch(Exception e){ U|QDV16f
e.printStackTrace(); |g{AD`
} finally{ '37b[~k4
try{ :[&X*bw[
if(ps!=null) { /_|1,x-Kx
ps.clearParameters(); T_dd7Ym'8
ps.close(); \NqC i'&
ps=null; D.e*IP1R
} {m?x},
}catch(SQLException e){} $} Myj'`r
DBUtils.closeConnection(conn); Z-?9F`}
} 3PGyqt(
} (!(bysi9
public long getLast(){ H#y"3E<s
return lastExecuteTime; Mg$Z^v|}0
} N@$%0!
public void run(){ qG qu/$bh
long now = System.currentTimeMillis(); '9gI=/29D
if ((now - lastExecuteTime) > executeSep) { 9lxT5Wg
//System.out.print("lastExecuteTime:"+lastExecuteTime); |<0@RCgM
//System.out.print(" now:"+now+"\n"); #rwR)9iC0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SJ-Sac58r
lastExecuteTime=now; BTyVfq
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executeUpdate(); `<n:D`{dZ
} `dZ|}4[1
else{ \zUsHK?L"t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NC}#P<U
} u|c+w)a
} v(O.GhJ@
} ;=OH=+Rl
//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 Xn=fLb(
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类写好了,下面是在JSP中如下调用。 'Ap5Aq
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<% a5M>1&j/eC
CountBean cb=new CountBean(); <GN?J.B
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Vvj]2V3
CountCache.add(cb); 8rYK~Sz
out.print(CountCache.list.size()+"<br>"); %-Z~f~<?
CountControl c=new CountControl(); w$4Lu"N:
c.run(); ULjzhy+(8
out.print(CountCache.list.size()+"<br>"); !Xi>{nV
%>