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: iI@(Bl]
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CountBean.java 5wI j:s
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/* 9=G
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* CountData.java *cc|(EM
* 3&Fqd
* Created on 2007年1月1日, 下午4:44 :i]g+</
* Cgn@@P5ZC
* To change this template, choose Tools | Options and locate the template under oI9-jW
* the Source Creation and Management node. Right-click the template and choose 1A{iUddR
* Open. You can then make changes to the template in the Source Editor. QW>(LG G=
*/ h<FEe~
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package com.tot.count; O;RNmiVoq
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/** 8zH/a
* UpqDGd7M
* @author }\d3
*/ $F~hL?"?
public class CountBean { Ffr6P
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private String countType; (=w ff5U
int countId; ,CjJO -
/** Creates a new instance of CountData */ hJ0m;j&4y
public CountBean() {} fZt3cE\
public void setCountType(String countTypes){ N0fXO
this.countType=countTypes; K9Bi2/N
} 5h>t4 [~
public void setCountId(int countIds){ /[Sy;wn
this.countId=countIds; UdX aC= Q
} #mbl4a
public String getCountType(){ Zq>}SR
return countType; zNQ|G1o
} <P<^,aC/j
public int getCountId(){ E3E$_<^
return countId; uT{.\qHo
} dWhF[q"
} Ujss?::`G
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CountCache.java Vr<ypyC
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/* O:(%m
* CountCache.java QLAyX*%B
* -cnlj
* Created on 2007年1月1日, 下午5:01 *!x/ia9
* +hd1|qa4
* To change this template, choose Tools | Options and locate the template under P%xz"l i
* the Source Creation and Management node. Right-click the template and choose `-)Fx<e
* Open. You can then make changes to the template in the Source Editor. o)IcAqN$H
*/ 5A*'@Fr'G
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package com.tot.count; parC~)b_
import java.util.*; 9{5 c}bX
/** /'0,cJnm
* dM3V2TT
* @author 0B[eG49
*/ sYY=MD
public class CountCache { /yj-^u\R
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ 7<c&)No;
public CountCache() {} S~4HFNe^&
public static void add(CountBean cb){ QprzlxB
if(cb!=null){ <jRs/?1R
list.add(cb); G q
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} {cBLm/C
} G.c@4Wz+
} cP MUu9du
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CountControl.java &tw
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/* ?W"9G0hTqM
* CountThread.java 6'N!)b^-
* 5CuK\<
* Created on 2007年1月1日, 下午4:57 uH-*`*
* T4{&@b
0*
* To change this template, choose Tools | Options and locate the template under CfnRcnms
* the Source Creation and Management node. Right-click the template and choose 'zhw]L;'g
* Open. You can then make changes to the template in the Source Editor. 0yxMIX
*/ 84*Fal~Som
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package com.tot.count; Wy%F
import tot.db.DBUtils; DqHVc)9
import java.sql.*; ^y"$k
/** =7`0hS<@F
* s(I7}oRWsL
* @author Cz_chK4
*/ __V6TDehJ$
public class CountControl{ `-N&cc
private static long lastExecuteTime=0;//上次更新时间 ?$^qcpJCp
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 WwDxZ>9jw
/** Creates a new instance of CountThread */ S
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public CountControl() {} V
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public synchronized void executeUpdate(){ VNbq]L(g
Connection conn=null; Lay+)S.ta[
PreparedStatement ps=null; Az2$\
try{
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conn = DBUtils.getConnection(); R`:NUGR
conn.setAutoCommit(false); ZR'q.y[k)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); U<
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for(int i=0;i<CountCache.list.size();i++){ <`q|6XWL
CountBean cb=(CountBean)CountCache.list.getFirst(); HH|&$C|64
CountCache.list.removeFirst(); a".uS4x
ps.setInt(1, cb.getCountId()); Wwf#PcC]
ps.executeUpdate();⑴ Mr(~
*
//ps.addBatch();⑵ Yn}_"FO'
} 9c=_p'G3Fw
//int [] counts = ps.executeBatch();⑶ -$4%@Z
conn.commit(); WLWE%bDP
}catch(Exception e){ 3EcmNwr
e.printStackTrace(); Cs
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} finally{ G?]E6R
try{ EhybaRy;C
if(ps!=null) { ?fEX&t,'
ps.clearParameters(); hqY9\,.C
ps.close(); ${ ~UA6
ps=null; 8E Y<^:
} 5 b[:B~J
}catch(SQLException e){} aM9St!i
DBUtils.closeConnection(conn); O.E
} `B6{y9J6
} GfU+'k;9
public long getLast(){ G1~|$X@@
return lastExecuteTime; Sh]x`3 ).
} fwRlqfi
public void run(){ @:xO5L}Io
long now = System.currentTimeMillis(); D.<CkDB
if ((now - lastExecuteTime) > executeSep) { &hba{!`y
//System.out.print("lastExecuteTime:"+lastExecuteTime); WL}6YSC
//System.out.print(" now:"+now+"\n"); 5e,Dk0d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); W&4`eB/4}
lastExecuteTime=now; H9w*U
executeUpdate(); @X/S
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} l#o43xr
else{ 5
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B<[;rk
} E!VAA=
} asW1GZO
} FV$= l
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//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 S_:(I^
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类写好了,下面是在JSP中如下调用。 $#@4i4TN-
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<% ),\>'{~5&
CountBean cb=new CountBean(); 1qUdj[Bj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); NI(`o8fN
CountCache.add(cb); "`"j2{9|e!
out.print(CountCache.list.size()+"<br>"); 0mj=\ j
CountControl c=new CountControl(); i:kWO7aP
c.run(); nHKEtKDd
out.print(CountCache.list.size()+"<br>"); 0m`7|80#P
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