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: U43PHcv_
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CountBean.java @0-<|,^]
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/* ]M-j_("&
* CountData.java z;2kKQZm
* NIQNzq?a^
* Created on 2007年1月1日, 下午4:44 bTb|@
* 8! pfy"
* To change this template, choose Tools | Options and locate the template under j@&F[ r
* the Source Creation and Management node. Right-click the template and choose zxT&K|
* Open. You can then make changes to the template in the Source Editor. jaFBz&P/#
*/ Xj.6A,}^
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package com.tot.count; ||0mfb
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/** @m<xpel
* OU/PB
* @author !QSL8v@c
*/ Jx.Jx~
public class CountBean { "tn]s>iAd=
private String countType; pbl;n|
int countId; E&7U |$
/** Creates a new instance of CountData */ l]uF!']f
public CountBean() {} s1?N&t8c
public void setCountType(String countTypes){ &Plc
this.countType=countTypes; )xoI H{
} xbvZ7g^
public void setCountId(int countIds){ ?FA} ;?v
this.countId=countIds; #JWW ;M6F
} Nw/4z$].J
public String getCountType(){ =NQDxt}
return countType; @9~6+BZOq
} VK[^v;
public int getCountId(){ zr-HL:js
return countId; 6H53FMqr
} ;S7MP`o@
} {M )Y6\v
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CountCache.java ?<%GYdus
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/* 3ktjMVy\
* CountCache.java &&nvv &a
* hV)D,oN3
* Created on 2007年1月1日, 下午5:01 }N&}6U
* H"=%|/1M0
* To change this template, choose Tools | Options and locate the template under kD8$ir'UYG
* the Source Creation and Management node. Right-click the template and choose ^yb3L1y
* Open. You can then make changes to the template in the Source Editor. Rr{mD#+
*/ tMR&>hM
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package com.tot.count; ~a^mLnY@
import java.util.*; YNRpIhb
/** F w)#[
* /q^)thJ~
* @author $BXZFC_1S
*/ qRZv[T%*Q
public class CountCache { +vIpt{733
public static LinkedList list=new LinkedList(); anxgD?<+B
/** Creates a new instance of CountCache */ I}q2)@
public CountCache() {} @@-n/9>vs
public static void add(CountBean cb){ jAie[5
if(cb!=null){ MX2]Q
list.add(cb); iVTC"v
} 07P/A^Mkx
} {E@Fk,
} %M]%[4eC
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CountControl.java
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/* A<fKO <d
* CountThread.java ;4>YPH
* I8TqK
* Created on 2007年1月1日, 下午4:57 MKf|(6;~
* #^4p(eZ[}
* To change this template, choose Tools | Options and locate the template under _kg<KD=P
* the Source Creation and Management node. Right-click the template and choose %UT5KYd!=N
* Open. You can then make changes to the template in the Source Editor. @a$_F3W
*/ LmWZ43Z"@
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package com.tot.count; m!Cvd9X=
import tot.db.DBUtils; }Go?j#
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import java.sql.*; d,8L-pT$FM
/** ' ^E7T'v%
* VHyH't_&s
* @author X'Q?Mh
*/ e=Ko4Ao2y
public class CountControl{ <`rmQ`(}s
private static long lastExecuteTime=0;//上次更新时间 %A64AJZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 KSDz3qe
/** Creates a new instance of CountThread */ b+Sq[
public CountControl() {} VwvL
public synchronized void executeUpdate(){ 1yC_/Va1
Connection conn=null; gB|>[6
PreparedStatement ps=null; -FpZZ8=,M2
try{ -@L7!,j
conn = DBUtils.getConnection(); tg-U x
conn.setAutoCommit(false); IJa6W`}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); fIe';a
for(int i=0;i<CountCache.list.size();i++){ '5V}Z3zJ/
CountBean cb=(CountBean)CountCache.list.getFirst(); ?1w{lz(P
CountCache.list.removeFirst(); \kWL:uU
ps.setInt(1, cb.getCountId()); iMjoatt
ps.executeUpdate();⑴ 9^;Cz>6s
//ps.addBatch();⑵ G5*"P!@6
} 2^ uP[
//int [] counts = ps.executeBatch();⑶ 7.)kG}q]
conn.commit(); J>Pc@,y
}catch(Exception e){ D+#OB|&Dn
e.printStackTrace(); yC \dM1X
} finally{ A.tXAOM(VW
try{ 7>.d*?eao\
if(ps!=null) { 3E9 )~$
ps.clearParameters(); `(tVwX4
ps.close(); [x{z}rYH
ps=null; ,+2!&"zD
} S:B$c>
}catch(SQLException e){} q8A ;%.ZLG
DBUtils.closeConnection(conn); f euATL]
} ,Tp:. "
} tV?-
public long getLast(){ *.%z
return lastExecuteTime; +@] ,JlYf
} m.F}9HI%hN
public void run(){ GdN9bA&,
long now = System.currentTimeMillis(); E? lK(C
if ((now - lastExecuteTime) > executeSep) { {g9*t}l4
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1.24ZX
//System.out.print(" now:"+now+"\n"); Y"H'BT!b}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ^^,cnDlm
lastExecuteTime=now; u00w'=pe)
executeUpdate(); Ic2Q<V}oq
} /cHUqn30a
else{ \k4tYL5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); JuW"4R
} Gh%R4)}
} tTEw"DL_-
} =csh=V@s
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 H4B|c42
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#4
类写好了,下面是在JSP中如下调用。 '/="bSF
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<% j(~e{HZ
CountBean cb=new CountBean(); 3d>8~ANi=%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !$u:[T_8
CountCache.add(cb); )J^5?A
out.print(CountCache.list.size()+"<br>"); @7HHi~1JK
CountControl c=new CountControl(); F8H4R7
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c.run(); 8:t!m>(*
out.print(CountCache.list.size()+"<br>"); c,CcKy;+
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