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: ohRjvJ'v|
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CountBean.java r)lEofX,g+
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/* B}n,b#,*
* CountData.java |9u OUE
* 0@[$lv;OS
* Created on 2007年1月1日, 下午4:44 8*W#DH!
* .I7pA5V{#
* To change this template, choose Tools | Options and locate the template under *T-<|zQ
* the Source Creation and Management node. Right-click the template and choose {o)L c6T8s
* Open. You can then make changes to the template in the Source Editor. qz+dmef
*/ H['N
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package com.tot.count; VyXKZ%\dQ/
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/** i5en*)O8
* ~FZ&.<s
* @author xu>9(,l
*/ V_R@o3kv;
public class CountBean { xR-%L
private String countType; p?*Q- f
int countId; iIvc43YV%
/** Creates a new instance of CountData */ 9%k2'iV7
public CountBean() {} zpzK>DH(
public void setCountType(String countTypes){ Cl5uS%g
this.countType=countTypes; zvvhFN2s
} $ZUdT
public void setCountId(int countIds){ 18|m)(W
this.countId=countIds; N,`$M.|?
} ,KF'TsFf
public String getCountType(){ #pT"BSz]
return countType; Vrjc~>X
} *U^6u/iH
public int getCountId(){ viW!,QQ(S
return countId; ({
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} Ar%%}Gx/
} .?D7dyU l1
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CountCache.java %oF}HF.
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/* S{Kiy#ltWc
* CountCache.java 61Bwb]\f/|
* }d[ kxo
* Created on 2007年1月1日, 下午5:01 bbtGXfI+SB
* dV*]f$wQ
* To change this template, choose Tools | Options and locate the template under +dWDxguE{w
* the Source Creation and Management node. Right-click the template and choose Y4OPEo 5o
* Open. You can then make changes to the template in the Source Editor. e{h<g>7
*/ rDD:7*z
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package com.tot.count; 7G:s2432
import java.util.*; }'5MK
/** 10G}{
* rK@8/?y5
* @author QMA%$
*/ !lREaSM
public class CountCache { P#E &|n7DT
public static LinkedList list=new LinkedList(); Yab%/z2:
/** Creates a new instance of CountCache */ _A M*@|p,
public CountCache() {} l3KVW5-!gS
public static void add(CountBean cb){ !xz eM VI
if(cb!=null){ O6Vtu Ws%
list.add(cb); $CxKuB(
} BIb4h
} $Ad{Z
} Eav[/cU
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CountControl.java jTf@l?|
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/* aC^\(wp[
* CountThread.java heltgRt
* )bA;?i
* Created on 2007年1月1日, 下午4:57 Bt[/0>i
* \@-@Y
* To change this template, choose Tools | Options and locate the template under f"B3,6m
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. >lmi@UN|k
*/ +ylTGSZS
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package com.tot.count; 'WMh8)
import tot.db.DBUtils; yID164&r
import java.sql.*; 1 da@3xaF
/** 3ovWwZ8&
* ];} Wfl
* @author Q;MT"=RW
*/ t$+?6E
public class CountControl{ T\:4qETQF]
private static long lastExecuteTime=0;//上次更新时间 7@C<oy_bb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x9NEFtqjm
/** Creates a new instance of CountThread */ ".f ;+wH
public CountControl() {} xpNH?#&
public synchronized void executeUpdate(){ h~A/ y!s
Connection conn=null; *zNYZ#
PreparedStatement ps=null; V
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try{ %`k6w3qI
conn = DBUtils.getConnection(); MtM%{=&_
conn.setAutoCommit(false); y9_V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~aw.(A?MI
for(int i=0;i<CountCache.list.size();i++){ ]~844Jp
CountBean cb=(CountBean)CountCache.list.getFirst(); ioaU*%
CountCache.list.removeFirst(); h}-3\8 >
ps.setInt(1, cb.getCountId()); 1ofKt=|=
ps.executeUpdate();⑴ |o,YCzy|5
//ps.addBatch();⑵ @<<<C?CTv
} K*\'.~[6
//int [] counts = ps.executeBatch();⑶ 909?_v
conn.commit(); d; [C6d
}catch(Exception e){ ?8HHA:GP
e.printStackTrace(); %/EVUN9=
} finally{ o-;E>N7t
try{ |HU@
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if(ps!=null) { yZd +^QN
ps.clearParameters(); H!vax)%-\
ps.close(); R= a|Blp
ps=null; liEPCWl&
} &vHoRY
}catch(SQLException e){} w|3z;-#Q;
DBUtils.closeConnection(conn); L%">iQOG#
} 01[NX? qEa
} :Y-{Kn6`_
public long getLast(){ z+x\(/
return lastExecuteTime; 2Fy>.*,?
} BW-`t-,E;
public void run(){ tv>>l%
long now = System.currentTimeMillis(); H/,gro
if ((now - lastExecuteTime) > executeSep) { YTAmgkF\4
//System.out.print("lastExecuteTime:"+lastExecuteTime); k")R[)92b?
//System.out.print(" now:"+now+"\n"); Z/Eb:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <wZQc
lastExecuteTime=now; tM2)k+fg
executeUpdate(); JROM_>mC
} +nUy,S?43
else{ m[i+knYX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 8 m5p_\&
} P
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} Q*~LCtrI
} Yaj0;Lo[wt
//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 ,_|]Ufr!a
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类写好了,下面是在JSP中如下调用。 f6 |KN+.
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<% l;af~ef)'
CountBean cb=new CountBean(); uC.K<jD%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -g)9R%>-
CountCache.add(cb); UU'|Xz9~
out.print(CountCache.list.size()+"<br>"); pqUCqo!m\
CountControl c=new CountControl(); `J]fcE%T0R
c.run(); ttXXy3G#
out.print(CountCache.list.size()+"<br>"); syk!7zfK
%>