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: L}j0a> =x4
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CountBean.java w^1Fi8+
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/* 7rHS^8'H&
* CountData.java wVq\FY%
* GPWr>B.{:S
* Created on 2007年1月1日, 下午4:44 'ho{eR@d
* g8'DoHJ*
* To change this template, choose Tools | Options and locate the template under MbXq`%
* the Source Creation and Management node. Right-click the template and choose F8+e,x
* Open. You can then make changes to the template in the Source Editor. o/,NG U
*/ )uLr?$qe
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package com.tot.count; zx1:`K0bi
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/**
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* $gMCR
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* @author wE).>
*/ =ex'22
public class CountBean { l>v{
private String countType; ?G?gy2
int countId; #\bP7a+
/** Creates a new instance of CountData */ :[M[(
public CountBean() {} &HM-g7|C0E
public void setCountType(String countTypes){ Y~n`~(
this.countType=countTypes; !5x
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} @<_`2eW'/R
public void setCountId(int countIds){ w5]l1}rl
this.countId=countIds; ~DLIz g7p!
} /f1'm@8;
public String getCountType(){ sa1mC
return countType; rdj@u47
} !;>(ie\
public int getCountId(){ )%du@a8
return countId; a%hGZCI
} r@T| e
} dyQh:u
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CountCache.java v5T9Y-{`
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/* }sMW3'V
* CountCache.java Q2C)tVK+
* )-&nxOP
* Created on 2007年1月1日, 下午5:01 ~SVQ;U)-
* QJ];L7Hbo
* To change this template, choose Tools | Options and locate the template under B[NJ^b|
* the Source Creation and Management node. Right-click the template and choose +Z?[M1g
* Open. You can then make changes to the template in the Source Editor. =cfm=+
*/ PW_`qP:
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package com.tot.count; R'EW7}&
import java.util.*; Mr6E/7g%
/** 8wiA
* ]+IVSxa!u
* @author f]}}yBte`
*/ I=YCQ VvA
public class CountCache { Zd>ZY,-5
public static LinkedList list=new LinkedList(); Ea`OT+#h(*
/** Creates a new instance of CountCache */ `I>], J/
public CountCache() {} `?SG XXC
public static void add(CountBean cb){ ^\YQ_/\~L
if(cb!=null){ 3%NE/lw1
list.add(cb); *IlQ5+3I
} +-HE'4mo
} *?Wtj
} TczXHT}G
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CountControl.java szn%wZW
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/* u'@Ely
* CountThread.java 5}SXYA}
* gY\mXM*^
* Created on 2007年1月1日, 下午4:57 !?r/ 4
* [i9[Mj
* To change this template, choose Tools | Options and locate the template under /$OIlu
* the Source Creation and Management node. Right-click the template and choose ^4hc+sh0D
* Open. You can then make changes to the template in the Source Editor. nE<J`Wo$f
*/ RQ5P}A
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package com.tot.count; <W|1<=z(
import tot.db.DBUtils; #f9qlM32
import java.sql.*; /a%KS3>V*
/** M;@Ex`+?i
* 2^bgC~2C1
* @author tnRJ#[Io
*/ tD^a5qPh
public class CountControl{ (v|`LmV
private static long lastExecuteTime=0;//上次更新时间 6+#,=!hF{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %9YA^ri
/** Creates a new instance of CountThread */ u p~@?t2
public CountControl() {} &`sR){R
public synchronized void executeUpdate(){ sBB:$X
Connection conn=null; #J3zTG(:@
PreparedStatement ps=null; #?5VsD8
try{ ,|QU] E
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conn = DBUtils.getConnection(); U:Fpj~E_w
conn.setAutoCommit(false); s|p(KWo2U
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "D!Dr1
for(int i=0;i<CountCache.list.size();i++){ xx}'l:}2]
CountBean cb=(CountBean)CountCache.list.getFirst(); k^yy$^=<
CountCache.list.removeFirst(); tJG (*
ps.setInt(1, cb.getCountId()); [sptU3,2U
ps.executeUpdate();⑴ SOYDp;j
//ps.addBatch();⑵ `bi
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} h?3f5G*&H
//int [] counts = ps.executeBatch();⑶ DMRs}Yz6
conn.commit(); 9Iy[E,j
}catch(Exception e){ 3V!W@[ }:
e.printStackTrace(); B4 <_"0
} finally{ I$F\(]"@
try{ o+R. u}|
if(ps!=null) { s~#?9vW
ps.clearParameters(); vkh;qPD
ps.close(); rcpvH}N:
ps=null; =1_j aDp
} DvU~%%(0^
}catch(SQLException e){} g')?J<z
DBUtils.closeConnection(conn); Z^C!RSQ
} (''$'5~
} *Y^5M"AB_
public long getLast(){ mrX}\p
return lastExecuteTime; wN$uX#W|
} PwRNBb}6
public void run(){ g9! dpP
long now = System.currentTimeMillis(); `~sf}S
:
if ((now - lastExecuteTime) > executeSep) { s'_$j$1
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7=AO^:=bx
//System.out.print(" now:"+now+"\n"); z, :+Oc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )vxVg*.Ee
lastExecuteTime=now; QZ_nQ3K
executeUpdate(); !Q\X)C
} Es_SCWJ
else{ %_cg|yy
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `,<>){c|
} REeD?u j
} HP1X\h!Ke
} )GQD*b
//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 Ykx&6M@t
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类写好了,下面是在JSP中如下调用。 )3d:S*ly
Yf%[6Y{
<% u9da]*\7y
CountBean cb=new CountBean(); Qq6%53
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m^(E:6T
CountCache.add(cb); \v B9fA:*
out.print(CountCache.list.size()+"<br>"); e/ppZ>
CountControl c=new CountControl(); 7~QwlU3n<F
c.run(); GN8`xR{J*
out.print(CountCache.list.size()+"<br>"); V~tu<"%
%>