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: CMYkxU
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CountBean.java }Q_ }c9?
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/* K}Lu1:~
* CountData.java _%<qZT
* f:h<tlob
* Created on 2007年1月1日, 下午4:44 yj
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* <#e!kWGR?
* To change this template, choose Tools | Options and locate the template under -aIB_
* the Source Creation and Management node. Right-click the template and choose zl$z> z )
* Open. You can then make changes to the template in the Source Editor. 0lpUn74F
*/ Oy yE0
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package com.tot.count; Kk/cI6`W
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/** j8ag}%
* 7G23D
* @author Wq*W+7=.
*/ d0-T\\U
public class CountBean { jn>RE
private String countType; %~qY\>
int countId; t<znz6
/** Creates a new instance of CountData */ ?^
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public CountBean() {} ;V4f6[<]'z
public void setCountType(String countTypes){ 4"Pf0PD:
this.countType=countTypes; ~tqDh(
} >~\CiV4^
public void setCountId(int countIds){ .q9i10C
this.countId=countIds; r#WAS2.TP
} >FReGiK$T
public String getCountType(){ 1lf]}V
return countType; ,%,.c^-
} ;r3|EA35
public int getCountId(){ yUu+68Z6
return countId; *@[+C~U
} "y=AVO
} *x&y24
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CountCache.java TXK82qTdf
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/* A{ a`%FAV
* CountCache.java };]f 3
* >A1;!kGE#
* Created on 2007年1月1日, 下午5:01 p`3$NCJN
* C07 U.nzh
* To change this template, choose Tools | Options and locate the template under *]* D^'
* the Source Creation and Management node. Right-click the template and choose rqYx\i?
* Open. You can then make changes to the template in the Source Editor. 5gY9D!;:0D
*/ I07_o"3>qr
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package com.tot.count; IT\
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import java.util.*; Y(P<9m:
/** </Ry4x^A
* $nW^Gqwj]1
* @author B;xGTl@8
*/ ~QE- $;
public class CountCache { K!_''Fg
public static LinkedList list=new LinkedList(); _hs\"W
/** Creates a new instance of CountCache */ -O?&+xIK&
public CountCache() {} -WK
public static void add(CountBean cb){ ,{u'7p
if(cb!=null){ -87]$ ax
list.add(cb); wv_<be[?*
} q.NvwJ
} 2q*aq%
} ~F=,)GE
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CountControl.java 9aZ^m$tAt
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/* !0
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* CountThread.java L64cCP*
* Q!"W)tD
* Created on 2007年1月1日, 下午4:57 ]~-vU{
*
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* To change this template, choose Tools | Options and locate the template under "=\@
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* the Source Creation and Management node. Right-click the template and choose 9V( esveq
* Open. You can then make changes to the template in the Source Editor. _=;lt O
*/ &%`Y>\@f
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package com.tot.count; =
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import tot.db.DBUtils; \]+57^8r
import java.sql.*; ;m cu(J
/** cWNWgdk,`V
* zCdzxb_h"
* @author #Do#e
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*/ JW-!m8
public class CountControl{ W;@9x1jKX
private static long lastExecuteTime=0;//上次更新时间 m5rJY/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 S2*ER
/** Creates a new instance of CountThread */ W^AY:#eX~Q
public CountControl() {} hCKx%&[^7
public synchronized void executeUpdate(){ y OLqIvN
Connection conn=null; R x.]m0
PreparedStatement ps=null; "ZLujpZcG
try{ e<[0H 8
conn = DBUtils.getConnection(); mtn+bV
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conn.setAutoCommit(false); fK{[=xMr@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); <UMT:`h1MZ
for(int i=0;i<CountCache.list.size();i++){ b&1-tYV
CountBean cb=(CountBean)CountCache.list.getFirst(); "~HV!(dRMC
CountCache.list.removeFirst(); #\)tz z
ps.setInt(1, cb.getCountId()); cXo^.u
ps.executeUpdate();⑴ }./_fFN@
//ps.addBatch();⑵ X ?l F,p
} +|=5zWI/
//int [] counts = ps.executeBatch();⑶ Lc:DJA
conn.commit(); eX@7f!uz
}catch(Exception e){ 3 @7<e~f
e.printStackTrace(); /P3s.-sL
} finally{ /K@{(=n
try{ p>@S61
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if(ps!=null) { WgK |r~
ps.clearParameters(); mC}!;`$8p
ps.close(); 2og8VI
ps=null; /NDuAjp[@
} p!~{<s]
}catch(SQLException e){} ;y{VdT
DBUtils.closeConnection(conn); J|BZ{T}d
} 0piBK=tE/
} 66+y@l1
public long getLast(){ ToB^/
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return lastExecuteTime; Y/1,%8n
} 8{GRrwQ>
public void run(){ 9IRvbE~2
long now = System.currentTimeMillis(); !dW77kLTg
if ((now - lastExecuteTime) > executeSep) { U8b1
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//System.out.print("lastExecuteTime:"+lastExecuteTime); [8K+zT5
//System.out.print(" now:"+now+"\n"); -Jtx9P
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); M5Twulz/w
lastExecuteTime=now; b:iZ.I
executeUpdate(); ;|Z;YK@20
} ;\$P;-VY
else{ joN}N }U
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); weOzs]uc
} [?$|
} B!(t<W8cu
} R "&(Ae?LR
//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 yq?_#r
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类写好了,下面是在JSP中如下调用。 28j=q-9Z
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<% ?]=fC{Rh
CountBean cb=new CountBean(); ikGH:{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~Lc>~!!t
CountCache.add(cb); #c0
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out.print(CountCache.list.size()+"<br>"); 0)8QOTeT
CountControl c=new CountControl(); K+` Vn
c.run(); lbES9o5
out.print(CountCache.list.size()+"<br>"); 5g-apod
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