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: AdDlS~\?
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CountBean.java Lgl%fO/<t
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/* Hy~kHBIL
* CountData.java CL oc
* gB,~Y511
* Created on 2007年1月1日, 下午4:44 kKwb)i
* VuZd
* To change this template, choose Tools | Options and locate the template under ;2-%IA,
* the Source Creation and Management node. Right-click the template and choose [A99e`
* Open. You can then make changes to the template in the Source Editor. 9BgR@b
*/ + HvEiY
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package com.tot.count; ew8f7S[
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/** ?v?b%hK!;
* [;yEG$)K
* @author H.#<&5f
*/ eCHT)35u
public class CountBean { X,dOF=OJL
private String countType; H|&[,&M>
int countId; CqGi
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/** Creates a new instance of CountData */ ,x#5 .Koz
public CountBean() {} D/wX
public void setCountType(String countTypes){ H0tjBnu
this.countType=countTypes; AB92R/
} SJ4[n.tPI
public void setCountId(int countIds){ q))rlMo
this.countId=countIds; oqeA15k$
} hJ[Z~PC\T0
public String getCountType(){ 6S*L[zBnA\
return countType; >;I$&
} }cUq1r-bW
public int getCountId(){ RQ}0f5~t
return countId; _?Q0yVH;,
} ? I7}4i7
} F2jZ3[P
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CountCache.java tB-0wD=PR
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/* Fo
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* CountCache.java ;VVKn=X=S=
* ?J[m)Uo/K
* Created on 2007年1月1日, 下午5:01 36ygI0V_
* Yn!)('FdT!
* To change this template, choose Tools | Options and locate the template under Lh eOGM
* the Source Creation and Management node. Right-click the template and choose P_Rh& gkuK
* Open. You can then make changes to the template in the Source Editor. 6@ B_3y
*/ T \Zf`.mt
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package com.tot.count; /1A3
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import java.util.*; !kAjne8]d
/** {p -q&k&R|
* /Z':wu\
* @author &d1|B`gL|
*/ V $'~2v{_
public class CountCache { fGK=lT$
public static LinkedList list=new LinkedList(); %+BiN)R*x
/** Creates a new instance of CountCache */ ;h|zNx0
public CountCache() {} `cu W^/c
public static void add(CountBean cb){ ddR*&.Y!a
if(cb!=null){ ~cC=DeX
list.add(cb); B4fMD]
} W@"s~I6
} OFc Lh
} HP/f`8
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CountControl.java e,*E`ol
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/* bA/,{R
* CountThread.java qIXo_H&\C
* 'MF|(`
* Created on 2007年1月1日, 下午4:57 TU-aL
* Tf0"9
* To change this template, choose Tools | Options and locate the template under >"Tivc5
* the Source Creation and Management node. Right-click the template and choose I[P43>F3
* Open. You can then make changes to the template in the Source Editor. h!@t8R
*/ mI$<+S1!
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package com.tot.count; aXOW +$,
import tot.db.DBUtils; '+%<\.$
import java.sql.*; 45?aV@
/** |->P|1
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* WR5@S&fU`
* @author y~16o
*/ HV*Dl$
public class CountControl{ roiUVisq*
private static long lastExecuteTime=0;//上次更新时间 DL*/hbG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 QB3vp4pBg@
/** Creates a new instance of CountThread */ |IN{8
public CountControl() {} )Id.yv}_
public synchronized void executeUpdate(){ moop.}O<
Connection conn=null; *#{V^}
PreparedStatement ps=null; VXfp=JE
try{ &>jSuvVT
conn = DBUtils.getConnection(); 9i^dQV.U=
conn.setAutoCommit(false); pgp@Zw)r)k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2cnyq$4k
for(int i=0;i<CountCache.list.size();i++){ ftaGu-d%
CountBean cb=(CountBean)CountCache.list.getFirst(); KR49Y>s<
CountCache.list.removeFirst(); 6ct'O**k*&
ps.setInt(1, cb.getCountId()); ?.*^#>-
ps.executeUpdate();⑴ ygN4%-[XA
//ps.addBatch();⑵ goJK~d8M*
} W`vgH/lSnZ
//int [] counts = ps.executeBatch();⑶ ulA||
conn.commit(); o.o$dg(r!
}catch(Exception e){ r2h{#2
e.printStackTrace(); Exu5|0AAE
} finally{ :gwM$2vv
try{ SJ
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if(ps!=null) { Qp?+G~*
ps.clearParameters(); ^KlW"2:
ps.close(); 8lNkY`P7s
ps=null; 8.Z9 i
} %}`zq8Q;
}catch(SQLException e){} j0X Jf<
DBUtils.closeConnection(conn); K}OY!|
} UG~/
} _ Vo35kA
public long getLast(){ ]-2Q0wTj
return lastExecuteTime; bE6:pGr
} 5`3Wua
public void run(){ 9w"kxAN
long now = System.currentTimeMillis(); Y!1x,"O'H
if ((now - lastExecuteTime) > executeSep) { wf,B/[,d
//System.out.print("lastExecuteTime:"+lastExecuteTime); SNUq
//System.out.print(" now:"+now+"\n"); LBw$K0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); R?Dc*,
lastExecuteTime=now; G+SMH`h
executeUpdate(); mne?r3d
} d#W>"Cqxqa
else{ >[qoNy;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p~evPTHnrX
} zm{U.Q
} nf2[hx@=U
} tDj/!L`
//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 gK#G8V-,
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类写好了,下面是在JSP中如下调用。 sI OT6L^7
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<% QIWfGVc-
CountBean cb=new CountBean(); 6");NHE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); d95 $w8>
CountCache.add(cb); -|WQs'%O
out.print(CountCache.list.size()+"<br>"); u]$e@Vw.
CountControl c=new CountControl(); |ZmWhkOX
c.run(); /4M~ 6LT`
out.print(CountCache.list.size()+"<br>"); VX+:C(m~
%>