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: <h[l)-86
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CountBean.java vgbk
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/* \r^*4P,,
* CountData.java ` 8OA:4).
* ^_o9%)RL(
* Created on 2007年1月1日, 下午4:44 ptvM>zw'~g
* w/Ej>OS
* To change this template, choose Tools | Options and locate the template under n=tg{_9f%
* the Source Creation and Management node. Right-click the template and choose +t`QHvxv
* Open. You can then make changes to the template in the Source Editor. eHQ3K#M#
*/ [/Ya4=C@
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package com.tot.count; ~ @Au <
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/** 9_5tA'Q
* (%^Bp\.02!
* @author XF=GmkO
*/ pGh A
public class CountBean { Xh*p\ $
private String countType; PN@[k:5(
int countId; FdVWj
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/** Creates a new instance of CountData */ f7Fr%*cO
public CountBean() {} Y/aNrIK7
public void setCountType(String countTypes){ km+}./@
this.countType=countTypes; ]'a9>o
} :?}>Q
public void setCountId(int countIds){ t|9vb
this.countId=countIds; 4uh~@ Lv
} 1H\5E~X
public String getCountType(){ <Fv7JPN%
return countType; \rT>&o .i
} VD $PoP
public int getCountId(){ kyZZ0
return countId; U6o]7j&6
} ;\f0II3
} 3g56[;Up?
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CountCache.java D(&Zq7]n
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/* hD7vjg&Z
* CountCache.java -<AGCiLz
* FW)~e*@8=
* Created on 2007年1月1日, 下午5:01 a[,p1}!_
* 5Q:49S47
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose {iCX?Sb
* Open. You can then make changes to the template in the Source Editor. HX,i{aWWy
*/ ({$rb-
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package com.tot.count; _;/+8=
import java.util.*; _PQk<QZ
/** !aJ6Uf%R
* biForT_no
* @author '|*e4n
*/ g&Uu~;jq]
public class CountCache { T1 1>&K)
public static LinkedList list=new LinkedList(); U-$nwji
/** Creates a new instance of CountCache */ 2S4SG\
public CountCache() {} ]r%fAmj
public static void add(CountBean cb){ kw7E<aF!
if(cb!=null){ yMmUOIxk\
list.add(cb); V&/Cb&~Uw
} b2j~"9
} O%aHQL%Sz
} 5{IbKj|
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CountControl.java ixoN#'y<"
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/* CL?=j| Ea
* CountThread.java ?(}~[
* ytV[x
* Created on 2007年1月1日, 下午4:57 rd24R-6
* YUyYVi7clq
* To change this template, choose Tools | Options and locate the template under [By|3bI
* the Source Creation and Management node. Right-click the template and choose b&d4(dk
* Open. You can then make changes to the template in the Source Editor. u@`y/,PX
*/ r
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package com.tot.count; *Uf>Xr&
import tot.db.DBUtils; Hq?dqg' %~
import java.sql.*; 1CJAFi>%D
/** 9C!b
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* 7xO~v23oe
* @author )wdd"*hv
*/ =+[`9
public class CountControl{ myd:"u,}9
private static long lastExecuteTime=0;//上次更新时间 g0IvcA
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 0xaK"\Q
/** Creates a new instance of CountThread */ t8.3
public CountControl() {} -[h|*G.J
public synchronized void executeUpdate(){ ~\<L74BB
Connection conn=null; ()n2 KT
PreparedStatement ps=null; 'TA
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try{ >McEuoZx9
conn = DBUtils.getConnection(); vWL|vR
conn.setAutoCommit(false); YTr+"\CkA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 5v=e(Ph+
for(int i=0;i<CountCache.list.size();i++){ m9-=Y{&/
CountBean cb=(CountBean)CountCache.list.getFirst(); h}DKFrHW;-
CountCache.list.removeFirst(); UA*Kuad
ps.setInt(1, cb.getCountId()); Q|U
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ps.executeUpdate();⑴ .*J /F$
//ps.addBatch();⑵ 1?Tj
} p9S>H
//int [] counts = ps.executeBatch();⑶ 4[Wwm
conn.commit(); XK)0Mt\
}catch(Exception e){ $s 'n]]Wq
e.printStackTrace(); gyT0h?xDt
} finally{ 1(e64w@
try{
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if(ps!=null) { o*oFCR]j
ps.clearParameters(); VssWtL
ps.close(); GLMpWD`Wo
ps=null; ,3!4
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} nUisC5HW
}catch(SQLException e){} D.ySnYzh
DBUtils.closeConnection(conn); 8`90a\t'Z
} wyLyPJv
} ^ohIJcI-
public long getLast(){ I8YCXh
return lastExecuteTime; . lNf.x#u
} r@
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public void run(){ 7 y$a=+D i
long now = System.currentTimeMillis(); oa`7ClzD
if ((now - lastExecuteTime) > executeSep) { aP"!}*
//System.out.print("lastExecuteTime:"+lastExecuteTime); K6|R ;r5e{
//System.out.print(" now:"+now+"\n"); Lg|d[*;'7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $I4Wl:(~}
lastExecuteTime=now; u1\r:q
executeUpdate(); oY7jj=z#T
}
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else{ 9`M7 -{
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P4+PY 8
} bfy=
} #&%>kfeJ)<
} w"?RbA
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 &
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类写好了,下面是在JSP中如下调用。 *dPbV.HCl
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<% 2.MY8}&WBu
CountBean cb=new CountBean(); 7:<A_OLi
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e^$JGh2
CountCache.add(cb); ;k,@^f8
out.print(CountCache.list.size()+"<br>"); :\y' ?d- Q
CountControl c=new CountControl(); H8 xhE~'t
c.run(); `PSjkF(
out.print(CountCache.list.size()+"<br>"); sz%_9;`dpL
%>