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$\0ag
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CountBean.java ]$K5 8C
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/* 0Q%I[f8
* CountData.java eJOo~HIWQ
* 0NsPo
* Created on 2007年1月1日, 下午4:44 )$Fw<;4
* -}qay@cDt
* To change this template, choose Tools | Options and locate the template under ),;h
* the Source Creation and Management node. Right-click the template and choose 7B _Wz9y
* Open. You can then make changes to the template in the Source Editor. 5;{*mJ:F
*/ Wi)N/^;n
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package com.tot.count; i+-Y"vRi
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/** O6-"q+H)
* F8m@mh*8>
* @author b4^a
zY
*/ t I+]x]m+
public class CountBean { ^YPw'cZZ&
private String countType; : B/u>
int countId; 7Il
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/** Creates a new instance of CountData */ .@(MNq{"6
public CountBean() {} Ky7-6$
public void setCountType(String countTypes){ z<"\I60Fe
this.countType=countTypes; U,/9fzgd
} ;hDIoSz
public void setCountId(int countIds){ $>~4RXC
this.countId=countIds; mpCKF=KL.
} mnMY)-6C
public String getCountType(){ #|xj*+)H
return countType; ]=^NTm,
} z81`Lhg6
public int getCountId(){ %cc<>Hi
return countId; wd:SBU~f5*
} vP<8,XG
} \]/6>yT
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CountCache.java G_p13{"IM
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/* C"}]PW
* CountCache.java /Bnh%6#ab
* IW|1)8d
* Created on 2007年1月1日, 下午5:01 yw?UA
* +QrbW
* To change this template, choose Tools | Options and locate the template under 9/GC8*+
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. W$Z""
*/ ?6^KY+ 5`C
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package com.tot.count; Y6%O 9b
import java.util.*; gJn_8\,C>Q
/** c;7ekj
* 9%uJ:c?
* @author u-Ip *1/wp
*/
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public class CountCache { 8J7<7Sx
public static LinkedList list=new LinkedList(); QXT*O
/** Creates a new instance of CountCache */ T xwZ3E
public CountCache() {} s2+s1%^Ll
public static void add(CountBean cb){ H"g
p
if(cb!=null){ ,e>N9\*
list.add(cb); (OK;*ZH+T@
} G0h7MO%x
} blB00
} 4[]4KKO3Q2
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CountControl.java au1(.(
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/* \xaK?_hv
* CountThread.java g*#.yC1/
* ?G!DYUK
* Created on 2007年1月1日, 下午4:57 q:v&wb%
* of:xj$dQ_
* To change this template, choose Tools | Options and locate the template under E^jb#9\R
* the Source Creation and Management node. Right-click the template and choose [<{+tAdn)
* Open. You can then make changes to the template in the Source Editor. '.DFyHsq
*/ ~lLIq!!\
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package com.tot.count; *9Nq^+
import tot.db.DBUtils; nz]+G2h
import java.sql.*; 6ax|EMw
/** djcCm5m
* 1vBXO bk
* @author pEE.%U
*/ 2V#(1Hc!
public class CountControl{ .),m7"u|
private static long lastExecuteTime=0;//上次更新时间 _gF )aE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Dx27 s
/** Creates a new instance of CountThread */ f?A*g$v
public CountControl() {} i/UHDqZ
public synchronized void executeUpdate(){ i~6qOlLD-
Connection conn=null; oos7x6
PreparedStatement ps=null; DrB PC@^
try{ FCEFg)c5=
conn = DBUtils.getConnection(); paW7.~3
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conn.setAutoCommit(false); V"@]PI pr
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (a i&v
for(int i=0;i<CountCache.list.size();i++){ $/Q*@4t
CountBean cb=(CountBean)CountCache.list.getFirst(); 7.l[tKh
CountCache.list.removeFirst(); g k[8'
ps.setInt(1, cb.getCountId()); "V;M,/Q|
ps.executeUpdate();⑴ TM|ycS'
//ps.addBatch();⑵ +
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} 7,2bR
//int [] counts = ps.executeBatch();⑶ Ie~#k[X
conn.commit(); J_A5,K*r|
}catch(Exception e){ I vQ]-A}N
e.printStackTrace(); zj^Ys`nl
} finally{ (TV ye4Z
try{ ,$96bF "#
if(ps!=null) { IPoNAi<b
ps.clearParameters(); QuJ)WaJkC
ps.close(); O?9&6x
ps=null; {\L /?#
} tQ:)j^\
}catch(SQLException e){} 1/YWDxo,
DBUtils.closeConnection(conn); w#5^A(NR
} ^MGgFS]G
} /K"koV;
public long getLast(){ RAQi&?Ko
return lastExecuteTime; C0X_t
} 8rXu^
public void run(){ H1>}E5^?
long now = System.currentTimeMillis(); ~ b;%J:
if ((now - lastExecuteTime) > executeSep) { v'*#P7%Kf
//System.out.print("lastExecuteTime:"+lastExecuteTime); g,!6,v@
//System.out.print(" now:"+now+"\n"); 1#9 Q1@'OS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); MGd 7Ont
lastExecuteTime=now; &C+pen)Z
executeUpdate(); nxP>IfSA
} 9air"4
else{ hSq3LoHV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d3AOuVUf
} :Uf\r
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} \4`~J@5Y
} u+GtH;<;
//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 ;5A
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类写好了,下面是在JSP中如下调用。 r(IQ)\GR
'dp3>4
<% vl<W`)'
CountBean cb=new CountBean(); i*' 6"
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); V_?5 cwZ
CountCache.add(cb); V6Y:l9
out.print(CountCache.list.size()+"<br>"); |~Hlv^6H
CountControl c=new CountControl(); w^?uBeqR
c.run(); T<"Hh.h
out.print(CountCache.list.size()+"<br>"); C{<qc,!4
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