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: j 2ag
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CountBean.java !/XNp QP
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/* |2j,
* CountData.java 90Ki.K 0
* wXQxZuk[
* Created on 2007年1月1日, 下午4:44 O+}py{ st
* "]S
* To change this template, choose Tools | Options and locate the template under + `|A/w
* the Source Creation and Management node. Right-click the template and choose q5(t2nNb
* Open. You can then make changes to the template in the Source Editor. &>JP.//spi
*/ mJUM#ry
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package com.tot.count; =NF0E8O
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/** zXY8:+f
* 3a?-UT!
* @author
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*/ 1+FVM\<&
public class CountBean { MGR:IOTa
private String countType; kUd]8Ff!
int countId; cRT'?w`}
/** Creates a new instance of CountData */ &i5@4,p y9
public CountBean() {} tMxde+$y
public void setCountType(String countTypes){ W+ S~__K
this.countType=countTypes; ?})A-$f ~
} `8!9Fp
public void setCountId(int countIds){ l_h:S`z.
this.countId=countIds; #Z%"
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} l0Q5q)U1A
public String getCountType(){ 0g?)j-
return countType; +RooU?Aq
} U^dfNi@q
public int getCountId(){ }DhqzKl
return countId; W@d&X+7e
} =)Xj[NNRT
} ~lj[> |\Oj
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CountCache.java T8^9*]:@c!
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/* &,&+p0CSI!
* CountCache.java N"70P/
* [}L~zn6>?a
* Created on 2007年1月1日, 下午5:01 c{M
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* ~5KcbGD~
* To change this template, choose Tools | Options and locate the template under ,X@o@W+L
* the Source Creation and Management node. Right-click the template and choose n~^SwOt~;5
* Open. You can then make changes to the template in the Source Editor. #3&@FzD_P
*/ Q-<]'E#\(
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package com.tot.count; qf? "v;
import java.util.*; &6sF wK
/** f$lb.fy5
* K\K& K~Z
* @author )3h\QE!z
*/ V^_A{\GK
public class CountCache { _T\ ~%
public static LinkedList list=new LinkedList(); J K/{IkF
/** Creates a new instance of CountCache */ ]\pi!oa
public CountCache() {} :&BPKqKp
public static void add(CountBean cb){ &L8RLSfX
if(cb!=null){ s=8H<'l
list.add(cb); H*W>v[>
} Os9SfL
} NEq_!!/sF
} tguB@,O
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CountControl.java m+c-"arIpA
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/* hP6f
* CountThread.java Df6i*Ko|
* ;.}L#'0j
* Created on 2007年1月1日, 下午4:57 im>(^{{r&
* zhn?;Fi
* To change this template, choose Tools | Options and locate the template under wps/{h,
* the Source Creation and Management node. Right-click the template and choose GHv6UIe&
* Open. You can then make changes to the template in the Source Editor. rS1 gFGrj
*/ `O\>vn
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package com.tot.count; Nv5^2^Sc=
import tot.db.DBUtils; [:X@|,1V!L
import java.sql.*; I*rUe#$
/** S!?T0c?>
* ^to*ET{0
* @author {hS!IOM
*/ ^6W}ZLp
public class CountControl{ _U~R
private static long lastExecuteTime=0;//上次更新时间 %vmd2}dA
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 iYXD }l;r
/** Creates a new instance of CountThread */ Nc+0_|,
public CountControl() {} MzvhE0ab
public synchronized void executeUpdate(){ C*Q7@+&
Connection conn=null; YmljHQP
PreparedStatement ps=null; !u7KgB<=/F
try{ /H'- }C
conn = DBUtils.getConnection(); B!'K20"gF
conn.setAutoCommit(false); 'w:ugb9]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); mE~WE+lw9
for(int i=0;i<CountCache.list.size();i++){ i c{I
CountBean cb=(CountBean)CountCache.list.getFirst(); {~apY,3
CountCache.list.removeFirst(); X'OpR
ps.setInt(1, cb.getCountId()); alJ0gc2?
ps.executeUpdate();⑴ ,hzRqFg2
//ps.addBatch();⑵ +`>7cy%cZ
} uda++^y:
//int [] counts = ps.executeBatch();⑶ 2s}S9
conn.commit(); dS1HA>c)O
}catch(Exception e){ UBd+,]"f
e.printStackTrace(); 7-S?RU]g
} finally{ k+_>`Gre}
try{ YJ~<pH
if(ps!=null) { gJ l^K
ps.clearParameters(); SK}jhm"y
ps.close(); Tg)F.):
ps=null; O?vh]o
} rxp|[>O<
}catch(SQLException e){} TQB)
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DBUtils.closeConnection(conn); e;6:U85LS
} }Y-V!z5z!
} )WvKRp r
public long getLast(){ NDRDP D
return lastExecuteTime; nWK8.&{.
} Jxl'!8t
public void run(){ O/eZ1YAC
long now = System.currentTimeMillis(); CVO_F=;
if ((now - lastExecuteTime) > executeSep) { 5 3pW:`
//System.out.print("lastExecuteTime:"+lastExecuteTime); \]>821r
//System.out.print(" now:"+now+"\n"); ]]p\1G
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ij]UAJ}t
lastExecuteTime=now; Lv+{@)
executeUpdate(); 1(;{w+nM
} mc]+j,d
else{ RZW=z}T+H
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "I56l2dxd
} 8i;1JA
} :s_o'8z7L
} |>}CoR7
//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 8YZ9
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类写好了,下面是在JSP中如下调用。 ]O;*Y{:Y
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<% U_VP\ 03
CountBean cb=new CountBean(); O n0!>-b,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +VVn@=&?
CountCache.add(cb); sd4eG
out.print(CountCache.list.size()+"<br>"); ^.J_ w
CountControl c=new CountControl(); ]DnAW'm
c.run(); 9o,Eqx4J
out.print(CountCache.list.size()+"<br>"); 0$Tb5+H5
%>