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: O}q(2[*i
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CountBean.java Hp-vBoEk
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/* @z7$1pl}
* CountData.java .jbT+hhM
* qJ<Ghd`8v
* Created on 2007年1月1日, 下午4:44 %51HJB}C]
* -n`2>L1
* To change this template, choose Tools | Options and locate the template under ,:?=j80m
* the Source Creation and Management node. Right-click the template and choose R ;3!?`
* Open. You can then make changes to the template in the Source Editor. w!m4
*/ Y .\<P*iO
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package com.tot.count; N1espc@j
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/** t%]b`ad
* >Gxh=**F
* @author %vjfAdC
*/ A7sva@}W
public class CountBean { UpCkB}OhR1
private String countType; *Au[{sR
int countId; #=aT Sw X
/** Creates a new instance of CountData */ @!2vS@f
public CountBean() {} yo"!C?82=
public void setCountType(String countTypes){ XFWo"%}w
this.countType=countTypes; mA0|W#NB
} -3&mgd
public void setCountId(int countIds){ +{"w5o<CO
this.countId=countIds; ]`_eaW?Ua
} RWINdJZ
public String getCountType(){ 0;x<0P
return countType; 5Z(#)sa0Og
} L QA6iZBP
public int getCountId(){ $5Tjo
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return countId; [HSN*LXe
} JD{AwE@Ro
} EF[I@voc
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CountCache.java =z
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/* tY6QhhuS:
* CountCache.java glgXSOj
* ,3FG' q2
* Created on 2007年1月1日, 下午5:01 5WU?Km
* %n:ymc
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* To change this template, choose Tools | Options and locate the template under ^?o> (K
* the Source Creation and Management node. Right-click the template and choose 5!}fd/}Uk
* Open. You can then make changes to the template in the Source Editor. ,S\AUUt%
*/ : tcqb2p
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package com.tot.count; {^*D5
import java.util.*; OA{PKC
/** d}(b!q9
* fGMuml?[ e
* @author g%T` 6dvT
*/ c-bTf$6}
public class CountCache { R:t
public static LinkedList list=new LinkedList(); DzE_p-
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/** Creates a new instance of CountCache */ wBIhpiJX0
public CountCache() {} SbN.z
public static void add(CountBean cb){ -<M'h
if(cb!=null){ >19j_[n@VC
list.add(cb); XCQPVSh
} l6k.`1.In
} N2e]S8-
} P~ 7p~ke
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CountControl.java `Uy'YfYF
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/* H|/U0;s
* CountThread.java +U*:WKdI?
* fD ?w!7f-1
* Created on 2007年1月1日, 下午4:57 Jw)-6WJ!uO
* }@Ou]o
* To change this template, choose Tools | Options and locate the template under <CY<-H
* the Source Creation and Management node. Right-click the template and choose V}+Ui]ie|I
* Open. You can then make changes to the template in the Source Editor. #JW~ &;
*/ (GXFPEH8
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package com.tot.count; YKG}4{T
import tot.db.DBUtils; [pYjH+<
import java.sql.*; px=r~8M9}
/** %6HJM| {H
* k9 NPC"
* @author g RBbL1
*/ F=r`'\JV[
public class CountControl{ o1]Ze F
private static long lastExecuteTime=0;//上次更新时间 1OW#_4w/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Q<d|OX
/** Creates a new instance of CountThread */ -Gmg&yQ9
public CountControl() {} n>i}O!agg
public synchronized void executeUpdate(){ e.?;mD
Connection conn=null; -Vhxnh S
PreparedStatement ps=null; Y<9]7R(\;
try{ UZb!tO2
conn = DBUtils.getConnection(); d0 qc%.s
conn.setAutoCommit(false); ^A' Bghy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;J&9l
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for(int i=0;i<CountCache.list.size();i++){ <A@qN95m
CountBean cb=(CountBean)CountCache.list.getFirst(); i.G"21M
CountCache.list.removeFirst(); !+Us) 'L
ps.setInt(1, cb.getCountId()); e]@R'oM?#`
ps.executeUpdate();⑴ w^wh|'u^_@
//ps.addBatch();⑵ J^)=8cy
} Y!w {,\3
//int [] counts = ps.executeBatch();⑶ ^.~m4t`U
conn.commit(); ;P!x/Ct
}catch(Exception e){ r>3y87
e.printStackTrace(); ]gG&X3jaKq
} finally{ (H-}z`sy/@
try{ ~e#QAaXD#5
if(ps!=null) { Q]<6i
ps.clearParameters(); "6zf-++%
ps.close(); ry!0~ir
ps=null; !J-oGs\ u
} ~#y( ]Xec2
}catch(SQLException e){} V4qv7
DBUtils.closeConnection(conn); &n-)Alx
} e<1)KqG
} +je{%,*
public long getLast(){ @]xHt&j
return lastExecuteTime; drK &
} ,R2;oF_
public void run(){ Lc5I?}:;L
long now = System.currentTimeMillis(); [ %:%C]4
if ((now - lastExecuteTime) > executeSep) { XL!^tMk
//System.out.print("lastExecuteTime:"+lastExecuteTime); rw]7Lr_>
//System.out.print(" now:"+now+"\n"); ;/=6~%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HlC[Nu^6U
lastExecuteTime=now; 6UnWtLE
executeUpdate(); O(CmdSk,
} a?P$8NLr
else{ Ze- MB0w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B96"|v$
} ] R-<v&O
} X;%*+xQ^
} V.^Z)iNf^
//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 uPQrDr5
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类写好了,下面是在JSP中如下调用。 ~ w,hJ `
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<% UcxMA%Pw7$
CountBean cb=new CountBean(); >nOzz0,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +!Lz]@9K
CountCache.add(cb); iDrQ4>
out.print(CountCache.list.size()+"<br>"); Y4)v>&H
CountControl c=new CountControl(); .BjnV%l7Id
c.run(); <Pg<F[eDM
out.print(CountCache.list.size()+"<br>"); TDR2){I
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