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~;~i)Eg
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CountBean.java ~BTm6*'h
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/* \8*j"@ !H
* CountData.java us5Zi# }
* K
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* Created on 2007年1月1日, 下午4:44 rp
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* fFC9:9<
* To change this template, choose Tools | Options and locate the template under !<h9XccN
* the Source Creation and Management node. Right-click the template and choose L})fYVX
* Open. You can then make changes to the template in the Source Editor. G,6`:l
*/ |CQjgI|;
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package com.tot.count; RKMF?:
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/** 6qV1_M#
* )jwovS?V
* @author f7 ew<c\
*/ 'M?pg$ta_V
public class CountBean { U4a8z<l$
private String countType; FME,W&_d
int countId; MC-Z6l2
/** Creates a new instance of CountData */ {>64-bU
public CountBean() {} 5y='1s[%
public void setCountType(String countTypes){ y]i}j,e0L
this.countType=countTypes; u<n['Ur}|
} W#d'SL#5
public void setCountId(int countIds){ [vBP,_Tjx
this.countId=countIds; tOF8v8Hd
} kSJ;kz,_
public String getCountType(){ ?TDmW8G}J
return countType; O d6'bO;G
} taVK&ohWx
public int getCountId(){ U/HF6=Wot
return countId; vGH]7jht
} ELG{xN=o
} MjBI1|*
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CountCache.java b*Hk}
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/* 7
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* CountCache.java ~s?y[yy6i
* DjZTr}%q
* Created on 2007年1月1日, 下午5:01 blG?("0!
* I8W9Kzf
* To change this template, choose Tools | Options and locate the template under #RdcSrw)W!
* the Source Creation and Management node. Right-click the template and choose <|3F('Q"
* Open. You can then make changes to the template in the Source Editor. ,
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*/ J| 46i
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package com.tot.count; Q^Vch(`&P
import java.util.*; 2nFr?Y3g,
/** (Q&jp!WU
* isnpSN"z
* @author C{-Dv-<A>
*/ h^."wv
public class CountCache { 8BY`~TZO$q
public static LinkedList list=new LinkedList(); E9.1~
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/** Creates a new instance of CountCache */ 't\sXN+1
public CountCache() {} (:+Wc^0
public static void add(CountBean cb){ m*e8j[w#
if(cb!=null){ qIy9{LF
list.add(cb); Vn^8nS
} O" [#g
} .(Z^[C}
} bL:+(/:
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CountControl.java B( wi+;
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/* vXSpn71Jb
* CountThread.java Y}\3PaUa
* 527u d^:
* Created on 2007年1月1日, 下午4:57 93.L887
* OtZtl*5
* To change this template, choose Tools | Options and locate the template under !cO<N~0*5x
* the Source Creation and Management node. Right-click the template and choose >^f]Lgp
* Open. You can then make changes to the template in the Source Editor. o}D7 $6
*/ !$-QWKD4
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package com.tot.count; pL.~z
import tot.db.DBUtils; v`jFWq8I,
import java.sql.*; WK SWOSJ
/** mL@7,GD
* 4%>tk 8 [
* @author !?B2OE
*/ @nj`T{*.
public class CountControl{ &4p~i Z
private static long lastExecuteTime=0;//上次更新时间 ?G5,x
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T< <N U"n
/** Creates a new instance of CountThread */ YL4yT`*
public CountControl() {} ?I.bC
public synchronized void executeUpdate(){ 57N<OQWf
Connection conn=null; @<1T&X{Z!
PreparedStatement ps=null; ?`SBGN;
try{ y0t-e
conn = DBUtils.getConnection(); x}7Xd P.2$
conn.setAutoCommit(false); 0w$1Yx~C
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ',Oc+jLR
for(int i=0;i<CountCache.list.size();i++){ pAtxEaXh
CountBean cb=(CountBean)CountCache.list.getFirst(); %8"Aq
CountCache.list.removeFirst(); i?F~]8
ps.setInt(1, cb.getCountId()); mndNkK5o
ps.executeUpdate();⑴ H//,qxDc
//ps.addBatch();⑵ 4d-"kx3X
} 6A} 45
//int [] counts = ps.executeBatch();⑶ y|#Fu
conn.commit(); \FIOFbwe
}catch(Exception e){ Nu}Zsb|{
e.printStackTrace(); !`dn# j
} finally{ rIj B{X{Z
try{
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if(ps!=null) { ( 2KopL
ps.clearParameters(); I \6^]pi,
ps.close(); )]JQlm:H
ps=null; L<N=,~
} $I3}%'`+
}catch(SQLException e){} }Do$oyAV$G
DBUtils.closeConnection(conn); V#-8[G6Ra
} 4L2TsuLw
} a&`Lfw"
public long getLast(){ ]u
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return lastExecuteTime; `[4{]jX+<
} Z@#kivcpz
public void run(){ g^2H(}frc
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { A@ G%*\UZ
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^<e(3S:
//System.out.print(" now:"+now+"\n"); ~,84E [VV
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2MKB(;k
lastExecuteTime=now; 9C1\?)"D^e
executeUpdate(); l9$"zEC
} [Kanj/
else{ oSs~*mf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !o`h*G-x
} `c_Wk]i
} {X&H
} ,-Yl%R.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 O ;B[ZMV
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类写好了,下面是在JSP中如下调用。 6.QzT(
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<% 09HqiROw
CountBean cb=new CountBean(); !JwR[X\f
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~jOk?^6
CountCache.add(cb); HS
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out.print(CountCache.list.size()+"<br>"); +@yTcz
CountControl c=new CountControl(); +zsB ~Vz
c.run(); k iY1
out.print(CountCache.list.size()+"<br>"); Ne2eBmY}(
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