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: x?RYt4 S
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CountBean.java iDV.C@
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/* $kd9^lj#[
* CountData.java @Q%<~b[y
* (!0fmL
* Created on 2007年1月1日, 下午4:44 tl^![Z
* y28 e=i
* To change this template, choose Tools | Options and locate the template under Rp_)LA
* the Source Creation and Management node. Right-click the template and choose !+T29QYK8
* Open. You can then make changes to the template in the Source Editor. ~'#,*kA:6
*/ N_R(i3c6U!
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package com.tot.count; aW(Hn[}^
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/** Rv)>xw
* +|zcjI'=O
* @author pN#RTb8o
*/ c&I"&oZ@&
public class CountBean { rA[wC%%
private String countType; LW*v/`@
int countId; Mh8s @g
/** Creates a new instance of CountData */ k.!m-5E
public CountBean() {} `,$PRN"]
public void setCountType(String countTypes){ o((!3H{D
this.countType=countTypes; y-lBaTE9
} dQJ)0!B
public void setCountId(int countIds){ `!@d$*:'
this.countId=countIds; r0,XR
} cc{^0JT
public String getCountType(){ BMYvxSsm
return countType; kR65{h"gZT
} :4/37R(~l8
public int getCountId(){ }N0v_Nas;v
return countId; J3c8WS{:
} Zce/&
} =_Ip0FfK!
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CountCache.java ;%!]C0?
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/* VRD:PVz
* CountCache.java ]La~Bh6;m
* '|@?R |i0
* Created on 2007年1月1日, 下午5:01 $$e"[g
* lky5%H
* To change this template, choose Tools | Options and locate the template under M6XpauR-
* the Source Creation and Management node. Right-click the template and choose _p;=]#+c&
* Open. You can then make changes to the template in the Source Editor. dzs(sM=
*/ #H.DnW
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package com.tot.count; xP-\)d-.aN
import java.util.*; [^0 S#,L
/** pYz\GSd
* N;R I
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* @author T7?cnK"
*/ S,vh
public class CountCache { a~&euT2
public static LinkedList list=new LinkedList(); ,$(a,`s)
/** Creates a new instance of CountCache */ 2 `U+
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public CountCache() {} "wnN
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public static void add(CountBean cb){ ^=[b]*V
if(cb!=null){ 'nN'bVl/
list.add(cb); D.*o^{w|
} k nljc^
} u{5+hZ
} QE+HL8c^s
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CountControl.java W]I+Rlv)U
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/* I6Ga'5bV
* CountThread.java #83pitcc
* q!AcMd\
* Created on 2007年1月1日, 下午4:57 (D2N_l(`<
* .O6(QI*
* To change this template, choose Tools | Options and locate the template under %/w%A:y#&
* the Source Creation and Management node. Right-click the template and choose HpIWH*
* Open. You can then make changes to the template in the Source Editor. =fK6P6'B
*/ yR1v3D4E
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package com.tot.count; c]68$;Z7
import tot.db.DBUtils; <lTLz$QE
import java.sql.*; #Q@~TW
/** 7mA:~- .u
* >hO9b;F}
* @author /~3kkM(Ty
*/ Mb=j'H<N@
public class CountControl{ J~|:Q.Rt`
private static long lastExecuteTime=0;//上次更新时间 c\OLf_Uf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ogu";p(
/** Creates a new instance of CountThread */ %r]V:d+
public CountControl() {} W~j>&PK,?
public synchronized void executeUpdate(){ pvhN.z
Connection conn=null; '$5Qdaj
PreparedStatement ps=null; Xx1e SX
try{ =w ! 6un
conn = DBUtils.getConnection(); #=,c8"O
conn.setAutoCommit(false); 3jjV
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); y'C
for(int i=0;i<CountCache.list.size();i++){ .4[M7)
CountBean cb=(CountBean)CountCache.list.getFirst(); D[dI_|59a
CountCache.list.removeFirst(); B7(bNr
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ H1r8n$h
//ps.addBatch();⑵ +}iuTqu5
} b<j*;n.
//int [] counts = ps.executeBatch();⑶ 5M\bH'1
conn.commit(); v]y=+* A
}catch(Exception e){ y wmC>`0p
e.printStackTrace(); [:8+ +#KD
} finally{ ),XDY_9K
try{ rmeGk&*R8
if(ps!=null) { v+C%t!dx
ps.clearParameters(); 0t%`jY~%
ps.close(); upiYo(sN.
ps=null; 7M<co,"
} ` >[Offhd
}catch(SQLException e){} $l_\9J913
DBUtils.closeConnection(conn); _ ( $U\FW
} 7{p6&xXx
} NIG*
}[}P
public long getLast(){ L[tq@[(IJ
return lastExecuteTime; lX64IvG8+o
} APyH.] mQ
public void run(){ EN5F*s@r
long now = System.currentTimeMillis(); Y%^qt]u.8
if ((now - lastExecuteTime) > executeSep) { \m#{{SGm
//System.out.print("lastExecuteTime:"+lastExecuteTime); 28>/#I9/]
//System.out.print(" now:"+now+"\n"); cH6J:0>W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !:Ob3Mq\
lastExecuteTime=now; *iJ>@vew
executeUpdate(); 7A^L$TY
} HjY! ]!4p
else{ \?vn0;R4
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !d&SVS^mo
} ^1bM=9]F0
} XA\wZV
|{
} ?u>A2Vc!
//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 %*OQH?pyx}
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类写好了,下面是在JSP中如下调用。 Iz8gZ:rd0
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<% a1z*Z/!5
CountBean cb=new CountBean(); 3x)jab
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); D!mx &O9
CountCache.add(cb); yT[)V[}
out.print(CountCache.list.size()+"<br>"); ,6aF~p;wI|
CountControl c=new CountControl(); [y"Yi PK
c.run(); yC[Q-P *rG
out.print(CountCache.list.size()+"<br>"); cUTG!
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