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: K[|P6J
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CountBean.java g`8
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/* 2|NyAtPb5
* CountData.java QsF<=b~
* \FY De
* Created on 2007年1月1日, 下午4:44 VX>t!JP p
* Z%n.:I<%ZV
* To change this template, choose Tools | Options and locate the template under D>x'3WYR
* the Source Creation and Management node. Right-click the template and choose LYq2A,wm$
* Open. You can then make changes to the template in the Source Editor. mlw BATi
*/ $XU$?_O
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package com.tot.count; +U/ "F|M
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/** (uK), *6B
* -K'84 bZ
* @author p*&LEjaVM4
*/ :ktX7p~
public class CountBean { MLIQ 8=
private String countType; O>F.Wf5g
int countId; [Z Gj7
/** Creates a new instance of CountData */ Cg\)BHv~
public CountBean() {} ieF 0<'iF
public void setCountType(String countTypes){ .-26 N6S
this.countType=countTypes; v*]Xur6e}
} YK+Z0ry
public void setCountId(int countIds){ .6/p4OR|
this.countId=countIds; r|F,\fF
} <@j
public String getCountType(){ Uus)2R7
return countType; np>!lF:
} KeOBbe
public int getCountId(){ __n"DLW
return countId; n|,Vm@zV
} MGC0^voe
} ! tPK"k
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CountCache.java
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/* `IRT w"
* CountCache.java !9cP NIi
* +~{nU'
* Created on 2007年1月1日, 下午5:01 n *0F
* o%>nu
* To change this template, choose Tools | Options and locate the template under nMoF;AdKm
* the Source Creation and Management node. Right-click the template and choose B;7s ]R
* Open. You can then make changes to the template in the Source Editor. I%|s
*/ 44{:UhJkx
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package com.tot.count; 5h^qtK
import java.util.*; (9_e>2_
/**
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* 00wH#_fm
* @author ]Oh>ECA|D
*/ CrX-?$
public class CountCache { ^B=z_0 *
public static LinkedList list=new LinkedList(); (y4Eq*n%!
/** Creates a new instance of CountCache */ cW/~4.v$
public CountCache() {} rtOW-cz
public static void add(CountBean cb){ C4TD@
if(cb!=null){ ^O:RS
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list.add(cb); _r)nbQm&
} oqo8{hrdHk
} )4~XZt1r
} Jpnp'
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CountControl.java RXvcy<
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/* \/%Q PE8
* CountThread.java u}0t`w:
* xW )8mv?4n
* Created on 2007年1月1日, 下午4:57 `fVA.%
* -*j;
* To change this template, choose Tools | Options and locate the template under BeCr){,3
* the Source Creation and Management node. Right-click the template and choose ]= D
* Open. You can then make changes to the template in the Source Editor. *4\ub:9
*/ ^w}Ib']X
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package com.tot.count; yf>,oNIAg
import tot.db.DBUtils; SygsZv&LZ
import java.sql.*; g+{MvSj$
/** ?UIb!k>
* NPq2C8:
* @author 6UP3Ij
*/ hrxASAfg6
public class CountControl{ 5S?Xl|8E
private static long lastExecuteTime=0;//上次更新时间 Ek\Zi#f<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 w5R9\<3L
/** Creates a new instance of CountThread */ YWd(xm"4
public CountControl() {} Ase 1 R=0
public synchronized void executeUpdate(){ ECfY~qK
Connection conn=null; Ok"wec+,
PreparedStatement ps=null; Nq1RAM
try{ 8u23@?
conn = DBUtils.getConnection(); ]qQB+]WN
conn.setAutoCommit(false); Fd0FG A&L
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); A[Xw |9
for(int i=0;i<CountCache.list.size();i++){ !LESRh?
CountBean cb=(CountBean)CountCache.list.getFirst(); ~$Yuxo
CountCache.list.removeFirst(); z`6KX93
ps.setInt(1, cb.getCountId()); xBd%e-r
ps.executeUpdate();⑴ ]sIFK
//ps.addBatch();⑵ ]z@]Fi33Y
} yrb%g~ELGn
//int [] counts = ps.executeBatch();⑶ HM
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conn.commit(); artS*fv3r
}catch(Exception e){ N4FG_N
e.printStackTrace(); <m\TZQBD
} finally{ v2SsfhT
try{ S+ x[1#r
if(ps!=null) { hD=D5LYAZ
ps.clearParameters(); 8 F 1ga15
ps.close(); KJ
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ps=null; *V+fRN4 W
} '/@VG_9L]
}catch(SQLException e){} |1$X`|S
DBUtils.closeConnection(conn); BW1O1zIh\
} v7RDoO]I
} iE{ SqX
public long getLast(){ eLWzd_ln
return lastExecuteTime; ![Y$[l
} ijT^gsLL
public void run(){ IEj`:]d
long now = System.currentTimeMillis(); Z r*ytbt
if ((now - lastExecuteTime) > executeSep) { FL}8h/
//System.out.print("lastExecuteTime:"+lastExecuteTime); @bE?WXY
//System.out.print(" now:"+now+"\n"); zj}efv<e
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w}0PtzOe
lastExecuteTime=now; Z!6G(zz:>
executeUpdate(); ~Y$1OA8
} ^^mi@&ApLD
else{ _TiF}b!hi
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ZH*?~ #
} &'j77tqOk
} B$n\m854
} dWEx55>,1
//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 m[rJFSpef
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类写好了,下面是在JSP中如下调用。 uhLW/?q.
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<% EJsb{$u
CountBean cb=new CountBean(); 3H2'HO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NiF*h~q
CountCache.add(cb); n~)%ou
out.print(CountCache.list.size()+"<br>"); (TsgVq]L
CountControl c=new CountControl();
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c.run(); 0
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out.print(CountCache.list.size()+"<br>"); 5VS<I\o}
%>