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: {*[\'!d--.
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CountBean.java T(AVlI6
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/* /R~1Zj2&
* CountData.java ak->ML
* \=+b}mKV
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* Created on 2007年1月1日, 下午4:44 wUiys/OVM
* !iH-#B-
* To change this template, choose Tools | Options and locate the template under =1O<E
* the Source Creation and Management node. Right-click the template and choose W3D c r@Dy
* Open. You can then make changes to the template in the Source Editor. I#m-g-J
*/ a\IP12F?
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package com.tot.count; 6lkl7zm
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/** %YSpCI
* F6o_b4l
* @author "VkTY|a
*/ 0VckocF
public class CountBean { XW -2~?$
private String countType; #O$
int countId; $={:r/R`i
/** Creates a new instance of CountData */ 1rKlZsZ#*
public CountBean() {} *+TH#EL2
public void setCountType(String countTypes){ P&j(,7
this.countType=countTypes; :ml2.vP
} $&$w Y/F
public void setCountId(int countIds){ ME;n^y\8
this.countId=countIds; CbPuoOl
} GuGOePV
public String getCountType(){ 28/ ADZ
return countType; c9kzOQ2n
} lc2 i`MC
public int getCountId(){ :C}2=
return countId; {r>.G7P6
} rsF\JQk
}
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CountCache.java |o2sbLp
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/* &ISb~5
* CountCache.java q}/WQ]p} <
* %]gn?`O
* Created on 2007年1月1日, 下午5:01 lz?;#U
* 3m>+-})d
* To change this template, choose Tools | Options and locate the template under 2:BF[c`
* the Source Creation and Management node. Right-click the template and choose J[A14z]#`
* Open. You can then make changes to the template in the Source Editor. N0K){
*/ R*oXmuOsYA
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package com.tot.count; "]m+z)lWd
import java.util.*; EyI}{6~F
/** }R)=S_j
* SG?Nsp^%`B
* @author
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*/ tV_t6x_.
public class CountCache { Fi.aC;sx
public static LinkedList list=new LinkedList(); m6MOW&
/** Creates a new instance of CountCache */ RbGJ)K!
public CountCache() {} 7R3fqU.Rq
public static void add(CountBean cb){ Z1ALq5
if(cb!=null){ l"{Sm6:;-
list.add(cb); a8dXH5_
} 65oWD-
} yJsH=5A
} jYVE8Y)my
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CountControl.java =?])['VaA
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/* V $|<
* CountThread.java 4"@GNk~e
* B-*E:O0y
* Created on 2007年1月1日, 下午4:57 /({;0I*!i
* !j1[$% =#
* To change this template, choose Tools | Options and locate the template under QN>7~=`
* the Source Creation and Management node. Right-click the template and choose Y4F6qyP)"
* Open. You can then make changes to the template in the Source Editor. !ph" mf$-
*/ T*I?9d{k
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package com.tot.count; A])P1c. 7"
import tot.db.DBUtils; Nwc!r(
import java.sql.*; Bi~:>X\[^6
/** sVoW=4V8
* <&pKc6+{
* @author '4OcZ/oI
*/ mPPk)qy
public class CountControl{ F52B~@.
private static long lastExecuteTime=0;//上次更新时间 dQgk.k
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _P,^_%}V06
/** Creates a new instance of CountThread */ WlV
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public CountControl() {} fd8!KO
public synchronized void executeUpdate(){ DjCx~@
Connection conn=null; W3&tJ8*3
PreparedStatement ps=null; JR9$.fGJ
try{ 8BXqZVm.
conn = DBUtils.getConnection(); u/Fj'*M
conn.setAutoCommit(false); ~%#mK:+
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }:z5t,u6
for(int i=0;i<CountCache.list.size();i++){ P20|RvE
CountBean cb=(CountBean)CountCache.list.getFirst(); |%D%0TR&Q
CountCache.list.removeFirst(); [U\(G
ps.setInt(1, cb.getCountId()); OQ4c#V?
ps.executeUpdate();⑴ m@rSz
//ps.addBatch();⑵ 7Bz*r0 9S
} ] c}91
//int [] counts = ps.executeBatch();⑶ 7ODaX.t->
conn.commit(); b^`AJK
}catch(Exception e){ W9J1=
e.printStackTrace(); +`bC%\T8?
} finally{ .~=HgOJ
try{ jN/C'\QL
if(ps!=null) { $_j1kx$
ps.clearParameters(); beZ(o?uK
ps.close(); .dq
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ps=null; !0 Q8iW:
} *]s&8/Gmb
}catch(SQLException e){} Xt,X_o2m|]
DBUtils.closeConnection(conn); FN
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} +=cam/A
} zW4O4b$T
public long getLast(){ .Gb+\E{M
return lastExecuteTime; mog9 jw
} }qC SS<a
public void run(){ &1)xoZ'\
long now = System.currentTimeMillis(); tfiqr|z
if ((now - lastExecuteTime) > executeSep) { .
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//System.out.print("lastExecuteTime:"+lastExecuteTime); uhn%lV]
//System.out.print(" now:"+now+"\n"); FMu!z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); PDw{R]V+
lastExecuteTime=now; RTd^ImV
executeUpdate(); sm s1%%~
} pbB2wt
else{ 3n(*E_n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); x3p9GAd#
} D6=HYqdj
} JmWR{du
} &?a.mh/8[[
//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 5RA<Z.
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类写好了,下面是在JSP中如下调用。 Y">4Qx4W
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<% lL2-.!]R
CountBean cb=new CountBean(); !Q[}s#g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); N+>'J23d!
CountCache.add(cb); I]sqi#h$2W
out.print(CountCache.list.size()+"<br>"); :{CFTc5:A
CountControl c=new CountControl(); Hptq,~_t
c.run(); sC6r.@[u8t
out.print(CountCache.list.size()+"<br>"); oMTY)`me
%>