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: 1}%B%*N
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CountBean.java wkUlrL/~
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/* , %9df+5k
* CountData.java hk[
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* CW&.NT
* Created on 2007年1月1日, 下午4:44 2c5-)Dt)T
* a^U~0i@[S
* To change this template, choose Tools | Options and locate the template under $za8"T*I
* the Source Creation and Management node. Right-click the template and choose d5`3wd]]'v
* Open. You can then make changes to the template in the Source Editor. AlXNg!j;5K
*/ 0Hxmm@X2
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package com.tot.count; ar9]"s+'
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/** ^(HUGl_
* ~`M\Ir
* @author $5D,sEC@
*/ wMqX)}>
public class CountBean { G3G#ep~)vC
private String countType; jRSUp
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int countId; a2'^8;U*_
/** Creates a new instance of CountData */ *!s;"U
public CountBean() {} y){
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public void setCountType(String countTypes){ uN([*'0Cg
this.countType=countTypes; 9RN-suE[
} D=m'pL/pl
public void setCountId(int countIds){ FC i U
this.countId=countIds; J_x13EaV0
} 9l,a^@Y:
public String getCountType(){ $6OkIP.
return countType; n!p<A.O7@
} &0 >Loja`^
public int getCountId(){ .Asv%p[W
return countId; 6KpHnSW
} q\m2EURco
} EkgE_8
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CountCache.java ])xx<5Jt4
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/* I)A`)5="5
* CountCache.java N(I&
* &l3iV88
* Created on 2007年1月1日, 下午5:01 T!Hb{Cg*
* 8!Vl
* To change this template, choose Tools | Options and locate the template under J5^'HU3
* the Source Creation and Management node. Right-click the template and choose bFe+m1Q_
* Open. You can then make changes to the template in the Source Editor. ,lZB96r0
*/ xx[9~z=d
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package com.tot.count; nqInb:
import java.util.*; uV!^,,~
/** 6d_'4B
* T:5fc2Ngv
* @author 1P~X8=9h
*/ cWoPB
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public class CountCache { 7;KwLT 9
public static LinkedList list=new LinkedList(); ZosP(Tdq
/** Creates a new instance of CountCache */ ?OkWe<:4
public CountCache() {} x>Zn?YR,"
public static void add(CountBean cb){ WZ.@UN,
if(cb!=null){ ^J$2?!~
list.add(cb); |&RU/ a
} 6@rMtQfI
} 0g+'/+Ho 4
} <YdE1{fm
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CountControl.java V5UF3'3;}
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/* _d5QbTe
* CountThread.java i\,-oO
* r"P|dlV-
* Created on 2007年1月1日, 下午4:57 gIjh:_ Pz
* ,yiX# ;j
* To change this template, choose Tools | Options and locate the template under $<}$DH_Y
* the Source Creation and Management node. Right-click the template and choose IZpP[hov
* Open. You can then make changes to the template in the Source Editor. 03q5e
*/ Yt;MV)
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package com.tot.count; C{U?0!^
import tot.db.DBUtils; }H^+A77v
import java.sql.*; #1OOU
/** &litXIvT>
* ?l9XAWt\
* @author 4 o Fel.o
*/ ynthDEo
public class CountControl{ |?,A]|j
private static long lastExecuteTime=0;//上次更新时间 sB7#
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .+$Q<L
/** Creates a new instance of CountThread */ 8WXQOo8
public CountControl() {} :tV*7S=)
public synchronized void executeUpdate(){ 3}}38A|4
Connection conn=null; [_k1jHr48N
PreparedStatement ps=null; JRB9rSN^
try{ EV]1ml k$
conn = DBUtils.getConnection(); 4h|c<-`>t
conn.setAutoCommit(false); {*G9|#[/@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ZrpU <
for(int i=0;i<CountCache.list.size();i++){ 6^]+[q}3
CountBean cb=(CountBean)CountCache.list.getFirst(); y
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CountCache.list.removeFirst(); 0XE4<U
ps.setInt(1, cb.getCountId()); |-:()yxs
ps.executeUpdate();⑴ "\w 7q
//ps.addBatch();⑵ bCRV\myd`
} :D~D U,e'
//int [] counts = ps.executeBatch();⑶ KcWN,!G
conn.commit(); Va"0>KX
}catch(Exception e){ zdB^S%cztS
e.printStackTrace(); @>,^":`#
} finally{
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try{ o#3ly-ht
if(ps!=null) { "@V Y
ps.clearParameters(); h4fJvOk|!
ps.close(); E(>=rD /+
ps=null; ,Vc6Gwm
} oH97=>
}catch(SQLException e){} +%<(E
DBUtils.closeConnection(conn); glO^yZ s
} ~Y^+M*
} Ni9/}bb
public long getLast(){ 9+Np4i@
return lastExecuteTime; |jGf<Bf5
} J!dm-L
public void run(){ }T(D7|^R
long now = System.currentTimeMillis(); <sb~ ^B
if ((now - lastExecuteTime) > executeSep) { P)Jgs
//System.out.print("lastExecuteTime:"+lastExecuteTime); n\mO6aJ
//System.out.print(" now:"+now+"\n"); /6)<}#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zu_8># i-
lastExecuteTime=now; o_izl\
executeUpdate(); Ri<u/ ]oR"
} ^UP`%egR
else{ 0yk]o5a++
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X8Bd3-B
} Dj"F\j 1
} ;AG8C#_
} 01 }D,W`
//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 n1Yp1"2b[
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类写好了,下面是在JSP中如下调用。 `'DmDg
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<% }7b%HTF=
CountBean cb=new CountBean(); OIGY`
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \j$&DCv
CountCache.add(cb); ">\?&0
out.print(CountCache.list.size()+"<br>"); '{cIAw/"n
CountControl c=new CountControl(); S\CCrje
c.run(); /:cd\A}
out.print(CountCache.list.size()+"<br>"); A#e%^{q$
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