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: t=(CCq_N,
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CountBean.java PzDekyl
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/* wtnC^d$
* CountData.java Bgj^n{9x
* <MBpV^Y}
* Created on 2007年1月1日, 下午4:44 -eoXaP{[
* ).1F0T
* To change this template, choose Tools | Options and locate the template under P>i[X0UnL
* the Source Creation and Management node. Right-click the template and choose vTU*6)
* Open. You can then make changes to the template in the Source Editor.
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*/ 7gcJ.,Z.
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package com.tot.count; J PK(S~
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/** -}9a%
* j]'7"b5
* @author ]728x["(19
*/ 6Z3L=j
public class CountBean { u3ns-e
private String countType; a$ FO5%o
int countId; VsM~$
)
/** Creates a new instance of CountData */
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public CountBean() {} ;4ETqi9
public void setCountType(String countTypes){ m<uBRI*I
this.countType=countTypes; "WE*ED
} tjTnFP/=
public void setCountId(int countIds){ pw5uH
this.countId=countIds; %ryYa
} +:?"P<'
public String getCountType(){ }grel5lq
return countType; m3i+b
} ]3iQpL
public int getCountId(){ i917d@r( <
return countId; G :JQ_w
} Dq G m
} R9`37(c9+
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CountCache.java %qqX-SF0C
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/* 2Ub!wee
* CountCache.java ,4tuWO)"
* !O}^ Y
* Created on 2007年1月1日, 下午5:01 a08`h.dyN
* /I/gbmc)
* To change this template, choose Tools | Options and locate the template under I c 2R\}q
* the Source Creation and Management node. Right-click the template and choose 2/m4|
* Open. You can then make changes to the template in the Source Editor. hFp\,QSx
*/ (B:+md\Q
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package com.tot.count; yTb#V"eR
import java.util.*; 9#X"m,SB
/** 7I`8r2H
* {N2MskK
* @author 84}Pu%
*/ 78fFAN`
public class CountCache { \&Zp/;n
public static LinkedList list=new LinkedList(); --chU5
/** Creates a new instance of CountCache */ +1o4l i
public CountCache() {} T>2_ r6;
public static void add(CountBean cb){ #%$U-ti
if(cb!=null){ kI|7o>}<
list.add(cb); M4`.[P4
} +#V.6i
} nA?Ks!9T
} EYD24
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CountControl.java gJC~$/2
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/* 3BzC'nplm
* CountThread.java 9`X}G`
* b>Em~NMu_
* Created on 2007年1月1日, 下午4:57 :[C"}mR1
* o!-kwtw`l
* To change this template, choose Tools | Options and locate the template under V>Vu)7
* the Source Creation and Management node. Right-click the template and choose f5ttQ&@FF
* Open. You can then make changes to the template in the Source Editor. y}bliN7;1e
*/ O~
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package com.tot.count; #Li6RSeW
import tot.db.DBUtils; M!)~h<YL
import java.sql.*; v%$c_'d
/** n/Fx2QC{
* l}MVk%[
* @author {GP#/5$=
*/ [ qx[ 0
public class CountControl{ WAqH*LB
private static long lastExecuteTime=0;//上次更新时间 gql^Inx<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x^]J^L45
/** Creates a new instance of CountThread */ vnS;T+NZSC
public CountControl() {} 3F ]30
public synchronized void executeUpdate(){ qb1JE[2F
Connection conn=null; s5cY>
PreparedStatement ps=null; %;MM+xVVX
try{ NA;OT7X[
conn = DBUtils.getConnection(); SWWeN#Q
conn.setAutoCommit(false); sf5 F$
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ~,O&A B
for(int i=0;i<CountCache.list.size();i++){ cy
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CountBean cb=(CountBean)CountCache.list.getFirst(); %-J}m
CountCache.list.removeFirst(); ;:A/WU.^
ps.setInt(1, cb.getCountId()); i_<GSUTTr/
ps.executeUpdate();⑴ '74*-yd
//ps.addBatch();⑵ p%ZOLoc)Y
} RHv|ijYy
//int [] counts = ps.executeBatch();⑶ ' |Ia-RbX
conn.commit(); m:x<maP#E
}catch(Exception e){ /JbO $A
e.printStackTrace(); NPjNkpWm&=
} finally{ :F`-<x/
try{ c>.=;'2
if(ps!=null) { `m+o^!SGe
ps.clearParameters(); Bb9/nsbE
ps.close(); #L`'<ge'g*
ps=null; %s*F~E
} 4IGn,D^
}catch(SQLException e){} /n-!dXi
DBUtils.closeConnection(conn); o7sIpE9
} w gU2q|
} =GJ)4os
public long getLast(){ ~b;u1;ne
return lastExecuteTime; h6~H5X
} ZBsV
public void run(){ bBg=X}9
long now = System.currentTimeMillis(); 7Q>bJ Ek7
if ((now - lastExecuteTime) > executeSep) { /:-Y7M*
//System.out.print("lastExecuteTime:"+lastExecuteTime); Q.i_?a
//System.out.print(" now:"+now+"\n"); @aY>pr5!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HyGu3
lastExecuteTime=now; EAZLo;
executeUpdate(); Z%$tV3a?
} 7;r Jr&.)
else{ ly( LMr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \9N
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} )PCh;P0C
} }=$>w@mJ
} i)=dp!Bx^
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 BBDt^$
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类写好了,下面是在JSP中如下调用。 D&*'|}RZ
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<% J>N^ FR9
CountBean cb=new CountBean(); &3CC |
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 6BH
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CountCache.add(cb); 7&w$@zs87
out.print(CountCache.list.size()+"<br>"); /5N`Euw
CountControl c=new CountControl(); p,K!'\
c.run(); G/4~_\YMq
out.print(CountCache.list.size()+"<br>"); f=paa/k0
%>