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: r+SEw ;
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CountBean.java S_ZLTcq<1
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/* T4Xtuu1
* CountData.java 4,gol?a
* =rtS#u
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* Created on 2007年1月1日, 下午4:44 yi sF5`+
* x GwTk
* To change this template, choose Tools | Options and locate the template under poTl|y @
* the Source Creation and Management node. Right-click the template and choose bkxk
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* Open. You can then make changes to the template in the Source Editor. -3u@hp_
*/ /rn"
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package com.tot.count; GJ.kkTMT
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/** P\Ai|"=&]
* ~6\& y
* @author nMTLD
*/ Cc@=?
public class CountBean { ]d[Rf$>vu0
private String countType; ^).WW
int countId; (s5<
/** Creates a new instance of CountData */ >6*(}L9
public CountBean() {} Y>xi|TWN
public void setCountType(String countTypes){ nXv 7OEpTx
this.countType=countTypes; w/?nUp
} lv=yz\
public void setCountId(int countIds){ BhOXXa{B
this.countId=countIds; fEx+gQW_
} .WBI%ci
public String getCountType(){ m(8jSGV
return countType; cxAViWsf
} MFf05\aDu
public int getCountId(){ :D<:N*9i
return countId; Oqd"0Qt-
} HyZVr2
} i,mrMi
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CountCache.java 1M7\:te*
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/* ox!|)^`$_
* CountCache.java 0@II&
* (45NZBs
* Created on 2007年1月1日, 下午5:01 <QYCo1_
* FE0qw1{qQ
* To change this template, choose Tools | Options and locate the template under HiQoRk
* the Source Creation and Management node. Right-click the template and choose l*F!~J3
* Open. You can then make changes to the template in the Source Editor. |WD,\=J2
*/ pe\Txg6
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package com.tot.count; X{5v?4wI
import java.util.*; 2$o2.$i81
/** &>&dhdTQ
* R59e&
* @author 3~cS}N T
*/ l9M#]*{
public class CountCache { f28gE7Y\a
public static LinkedList list=new LinkedList(); f?/|;Zo4
/** Creates a new instance of CountCache */ [z
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public CountCache() {} n@G:e-m{A
public static void add(CountBean cb){ \e`6=Q%
if(cb!=null){ FBR$,j;Y
list.add(cb); 1<XiD3H;
} kA7~Yu5|
} c%q}"Y0oh
} J0IdFFZ|w
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CountControl.java !L&=?CX
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/* ^2&O3s
* CountThread.java O!#L#u53
* \SYPu,ZT
* Created on 2007年1月1日, 下午4:57 &Iv\jhq
* n;-x!Gs
* To change this template, choose Tools | Options and locate the template under btUUZ"q<
* the Source Creation and Management node. Right-click the template and choose ""25ay
* Open. You can then make changes to the template in the Source Editor. NYSj^k;^(z
*/ -IpV'%nX;
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package com.tot.count; ^
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import tot.db.DBUtils; DBj;P|L_
import java.sql.*; _ 4~ng#M*
/** gp#bQ
* 4f@havFIJ
* @author J]n7| L
*/ u\Nw:Uu i
public class CountControl{ "'Q" (S
private static long lastExecuteTime=0;//上次更新时间 kr/1Dsr4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {u(}ED#p
/** Creates a new instance of CountThread */ x?k
public CountControl() {} A^T~@AO
public synchronized void executeUpdate(){ SX_kr^#
Connection conn=null; <6d{k[7fz)
PreparedStatement ps=null; +XU$GSw3(
try{ xWC\954
conn = DBUtils.getConnection(); 1jZDw~
conn.setAutoCommit(false); TS\A`{^T
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *3w/`R<\
for(int i=0;i<CountCache.list.size();i++){ z/eU^2V
CountBean cb=(CountBean)CountCache.list.getFirst(); FT|/WZR
CountCache.list.removeFirst(); 9,iq"dQ
ps.setInt(1, cb.getCountId()); sx;V,"Y
ps.executeUpdate();⑴ S7Iu?R_I
//ps.addBatch();⑵ C:tSCNH[
} [I+)Ak5
//int [] counts = ps.executeBatch();⑶ +WV_`Rx#
conn.commit(); e 5WdK
}catch(Exception e){ >6.[i@RmWU
e.printStackTrace(); Xa? 6#
} finally{ )+jK0E1
try{ g6[/F-3Qlf
if(ps!=null) { Ovl?j&8
ps.clearParameters(); SU_]C+
ps.close(); [T}%q"<
ps=null; %#S "~)
} @w#gRQCl
}catch(SQLException e){} v$.JmL0^J
DBUtils.closeConnection(conn); "lv:hz
} 1OiZNuI:E
} j{7ilo(i
public long getLast(){ )CwMR'LV
return lastExecuteTime; r2E>sHw
} 6*(h9!_T1
public void run(){ vUo.BA#;.b
long now = System.currentTimeMillis(); v2Qc}o
if ((now - lastExecuteTime) > executeSep) { a.Rp#}f
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1,%#O;ya
//System.out.print(" now:"+now+"\n"); ^H\-3/si*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); aowPji$H
lastExecuteTime=now; W[1f]w3
executeUpdate(); Pt PGi^
} Dj,+t+|
else{ &G7)s%q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); w{:Oa7_A
} +AgkPMy
} !"Oj$c
-
} ^?K?\
//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 2d>d(^
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类写好了,下面是在JSP中如下调用。 U!;aM*67
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<% :C|>y4U&(s
CountBean cb=new CountBean(); g'}`FvADi
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); u]]5p[|S
CountCache.add(cb); [)J49
out.print(CountCache.list.size()+"<br>"); >DL-Q\U
CountControl c=new CountControl(); R>e3@DQ~
c.run(); XTi0,e]5{u
out.print(CountCache.list.size()+"<br>"); $3]E8t
%>