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: zdem}kBIe
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CountBean.java U$DZht4>u
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/* aVHID{Gf Z
* CountData.java +uF}mZS^
* \a0{9Xx F
* Created on 2007年1月1日, 下午4:44 ~c&sr5E
* Vxrj(knck,
* To change this template, choose Tools | Options and locate the template under :)Es]wA#HZ
* the Source Creation and Management node. Right-click the template and choose ,y"vf^BE.
* Open. You can then make changes to the template in the Source Editor. z z]~IxQ
*/ A]Hz?i
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package com.tot.count; &b~X&{3,
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/** kqX%y
* pno}`Cer
* @author MYV3</Xj*
*/ 1
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public class CountBean { C<C^7-5
private String countType; e`a4Gr
int countId; lNc0znY
/** Creates a new instance of CountData */ _3u3b/%J?
public CountBean() {} ~9@527m<',
public void setCountType(String countTypes){ >&>EjK4?
this.countType=countTypes; XRM/d5
} m{>"
public void setCountId(int countIds){ x| D|d}
this.countId=countIds;
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} [<
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public String getCountType(){ fb0)("_V
return countType; %qJgtu"8
}
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public int getCountId(){ r9-ayp#pC
return countId; $EIKi'!8
} N:'GNMu
} YG?4DF
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CountCache.java [+5g 9tBJ
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/* e6J>qwD?
* CountCache.java 3bd`q
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* w&}<b%l
* Created on 2007年1月1日, 下午5:01 vx6lud0k}
* g~|vmVBua
* To change this template, choose Tools | Options and locate the template under ~f[;(?39xZ
* the Source Creation and Management node. Right-click the template and choose DdISJWc'`5
* Open. You can then make changes to the template in the Source Editor. +MYrNR.p
*/ 5s%e9x|kP
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package com.tot.count; Q6 o1^s
import java.util.*; _8SB+s*
/** {{bwmNv"
* IrRe6nf@K
* @author F`F|.TX
*/ Y1AZ%{^0a
public class CountCache { LB.B w
public static LinkedList list=new LinkedList(); +F,])p4,]i
/** Creates a new instance of CountCache */ p4\sKF8-
public CountCache() {} y] 9/Xr/
public static void add(CountBean cb){ uDcs2^2l
if(cb!=null){ 9;n*u9<
list.add(cb); 1W.oRD&8j/
} E!WlQr:b$
} "7fEL:|j
} sm?b,T/
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CountControl.java Z9h4 pd
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/* g;q.vHvsc"
* CountThread.java @b2?BSdUp
* /EHO(d!<
* Created on 2007年1月1日, 下午4:57 T.QJ#vKO0
* $\k)Y(&
* To change this template, choose Tools | Options and locate the template under S^i8VYK,C5
* the Source Creation and Management node. Right-click the template and choose K5<2jl3S
* Open. You can then make changes to the template in the Source Editor. J pj[.Sq
*/ B`nI]_
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package com.tot.count; Vnb@5W2\
import tot.db.DBUtils; VqD_FS;E
import java.sql.*; iz [IK%K
/** U![$7k>,pr
* Dbx zqd
* @author h1B_*L
*/ xe.f]a
public class CountControl{ xHx_!
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private static long lastExecuteTime=0;//上次更新时间 [(3 %$?[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 03 iy[~Y2
/** Creates a new instance of CountThread */
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public CountControl() {} ~ e<,GUx(]
public synchronized void executeUpdate(){ D;48VK/Q
Connection conn=null; Zy)iNNtn
PreparedStatement ps=null; '%+LQ"Bp
try{ Cnc=GTRi
conn = DBUtils.getConnection(); zLxuxf~4@
conn.setAutoCommit(false); [P6A$HC<
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7bGOE_r
for(int i=0;i<CountCache.list.size();i++){ >pol'=
CountBean cb=(CountBean)CountCache.list.getFirst(); cN2Pl%7
CountCache.list.removeFirst(); n Jz* }=
ps.setInt(1, cb.getCountId()); uHZjpMoM
ps.executeUpdate();⑴ xrlyph5mE
//ps.addBatch();⑵ (Xzq(QV
} Gw6Odj
//int [] counts = ps.executeBatch();⑶ SEu:31k{o
conn.commit(); SN}3
}catch(Exception e){ Xrc{wDn
e.printStackTrace(); wT3D9N.
} finally{ S,'ekWVD
try{ K0@bh/i/^
if(ps!=null) { :YLYCVi|
ps.clearParameters(); GsD?Z%t~%
ps.close(); @QYCoEU8J
ps=null; P3a]*> .,
} z)eNM}cF
}catch(SQLException e){} %3=T7j
DBUtils.closeConnection(conn); u^2/:L
} :.{d,)G
}
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public long getLast(){ ]|Ie E!6
return lastExecuteTime; hr&UD| E=
} "cOBEhn%l
public void run(){ m<;MOS
long now = System.currentTimeMillis(); ulEtZ#O{_
if ((now - lastExecuteTime) > executeSep) { 3+C;zDKa
//System.out.print("lastExecuteTime:"+lastExecuteTime); 5YUe>P D
//System.out.print(" now:"+now+"\n"); +,i_G?eX
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QD-Bt=S7l
lastExecuteTime=now; MP
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executeUpdate(); r'|ei ,
} wXYT(R
else{ !WB3%E,I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >*|Eyv_
} . 7Pp'-hK
} DU5rB\!.~
} Y{t}sO%A
//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 _? $')P|
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类写好了,下面是在JSP中如下调用。 t`Xx\
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<% "HJQAy?W
CountBean cb=new CountBean(); R&'Mze fb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sAK&^g
CountCache.add(cb); dJb7d`
out.print(CountCache.list.size()+"<br>"); SM<qb0
CountControl c=new CountControl(); ,[_)BM
c.run(); Kr4%D*
out.print(CountCache.list.size()+"<br>"); daf-B-
%>