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: c{/R?<
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CountBean.java UGO;5!
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/* U~:H>
* CountData.java j;-Wf6h{
* 2 L4[~>
* Created on 2007年1月1日, 下午4:44 )_jboaNzwI
* _:m70%i
* To change this template, choose Tools | Options and locate the template under FQ<x(&/NF
* the Source Creation and Management node. Right-click the template and choose _Rii19k
* Open. You can then make changes to the template in the Source Editor. k-|g
*/ jy!]MAP#Gk
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package com.tot.count; M#'7hm6
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/** 8/aJ4w[A
* =IMmtOvJ
* @author 3$!QP
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*/ ]AY 4bm
public class CountBean { Ww-x+U\l
private String countType; ..8t1+S6]
int countId; #AGO~#aK
/** Creates a new instance of CountData */ S!8<|WO^t
public CountBean() {} uBbQJvL
public void setCountType(String countTypes){ .Od:#(aq
this.countType=countTypes; :b44LXKCP
} ]%6%rq%9C
public void setCountId(int countIds){ uQO5GDuK>
this.countId=countIds; caQ1SV^{9
} ^@V*:n^
public String getCountType(){ 1$T`j2s
return countType; !.j{vvQ/
} Qf=^CQ=lV
public int getCountId(){ $vXY"-k
return countId; -t4:%-wv
} MF"*xr v
} S5hc@^|0Z
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CountCache.java -w"I
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/* :g|.x
* CountCache.java F-3=eKZ
* *1dZs~_
* Created on 2007年1月1日, 下午5:01 W8 g13oAu"
* }'P|A
* To change this template, choose Tools | Options and locate the template under uBww
* the Source Creation and Management node. Right-click the template and choose 4~Cf_`X}]
* Open. You can then make changes to the template in the Source Editor. Jq` Dvz
*/ G ky*EY
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package com.tot.count; j_rO_m <8
import java.util.*; nN{DO:_o
/** @sn:%/x _
* g&g:HH:
* @author RDbNC v#
*/ Wmd@%K
public class CountCache { nr]=O`Mvh
public static LinkedList list=new LinkedList(); %_E5B6xi{
/** Creates a new instance of CountCache */ y05!-G:Y\
public CountCache() {} %_Vz0
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public static void add(CountBean cb){ HAO-|=c4
if(cb!=null){ [s^pP2
list.add(cb); /1LN\Eu
} ]&]G
} 9mDdX
} -I5]#%eX^
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CountControl.java GcRH$,<XG
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/* =r/K#hOR\J
* CountThread.java ^IiA(?8
* 28^/By:J
* Created on 2007年1月1日, 下午4:57 #6@hVR.
* |gA@$1+}
* To change this template, choose Tools | Options and locate the template under 9q?knMt
* the Source Creation and Management node. Right-click the template and choose 5]*lH t
* Open. You can then make changes to the template in the Source Editor. esSj
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*/ mfZbo#KS#v
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package com.tot.count; .K~V DUu
import tot.db.DBUtils; On);SN'
import java.sql.*; k`>qb8,
/** h:Gs9]Lvtv
* =&pR=vl
* @author x}a?B
*/ GThGV"
public class CountControl{ ,zZH>P
private static long lastExecuteTime=0;//上次更新时间 eM$a~4!d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %.
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/** Creates a new instance of CountThread */ E~q3o*
public CountControl() {} Ds]
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public synchronized void executeUpdate(){ Eo$l-Hl5=
Connection conn=null; %u%;L+0Q[
PreparedStatement ps=null; 1<@lM8&.kO
try{ 7vgRNzZoq
conn = DBUtils.getConnection(); iOa<=
conn.setAutoCommit(false); 3SWDPy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ]kNxytH\o
for(int i=0;i<CountCache.list.size();i++){ {0j,U\ kb
CountBean cb=(CountBean)CountCache.list.getFirst(); X{xkXg8h
CountCache.list.removeFirst(); ,Z|O y|+'
ps.setInt(1, cb.getCountId()); rIPg,4y*S!
ps.executeUpdate();⑴ fQ~~%#z1
//ps.addBatch();⑵ ;,Vdj[W$>
} W\<OCD%X
//int [] counts = ps.executeBatch();⑶ d3E N0e+^
conn.commit(); WClprSl8
}catch(Exception e){ dh]Hf,OLF
e.printStackTrace(); <8%+-[(
} finally{ vH6(p(l
try{ ~C
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if(ps!=null) { j*8Ze!^
ps.clearParameters(); %zc.b
ps.close(); !pe[H*Cy
ps=null; XKp(31])
} <2j$P Y9
}catch(SQLException e){} 2O(k@M5E?
DBUtils.closeConnection(conn); 1;./e&%%
} 5D3&E_S
} \W_ Dz*N
public long getLast(){ ++w{)Io Z
return lastExecuteTime; ~+ae68{p
} U'b}%[
public void run(){ LkeYzQH/l
long now = System.currentTimeMillis(); xg%{p``
if ((now - lastExecuteTime) > executeSep) { B7A.~'=
//System.out.print("lastExecuteTime:"+lastExecuteTime); :zC=JvKT
//System.out.print(" now:"+now+"\n"); MeV4s%*O+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?>=vKU5
lastExecuteTime=now; !U5Cwq
executeUpdate();
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} M2:3k
else{ )jI4]6
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .h
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} QncjSaEE
} S%
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} %xx;C{g;a
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Qmd2C&Xw
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类写好了,下面是在JSP中如下调用。 zxv y&
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<% "}uu-5]3
CountBean cb=new CountBean(); WFug-#;e
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); V!e`P
CountCache.add(cb); DS|x*w'I
out.print(CountCache.list.size()+"<br>"); ieEtC,U
CountControl c=new CountControl(); ENYc.$r
c.run(); w0>5#jq#r
out.print(CountCache.list.size()+"<br>"); f:t5`c.
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