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: L:|X/c9r[
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CountBean.java c,3'wnui
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/* B,BOzpb(
* CountData.java !mpMa]G3
* 1kz9>;Ud6
* Created on 2007年1月1日, 下午4:44 :,xyVb+
* c%xED%X9
* To change this template, choose Tools | Options and locate the template under wHBHkz
* the Source Creation and Management node. Right-click the template and choose 2|T|K?R^
* Open. You can then make changes to the template in the Source Editor. !0!P.Q8>&
*/ UY }9
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package com.tot.count; @1J51< x
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/** YYZs#_
* =:CGl
* @author ^cKv JSY
*/ R"9oMaY
public class CountBean { a `[?,W:q
private String countType; jFJW3az@z
int countId; VrnK)za*H
/** Creates a new instance of CountData */ "2vNkO##
public CountBean() {} +[ZMrTW!0C
public void setCountType(String countTypes){ yPzULO4
this.countType=countTypes; [pRVZV
} -Z/6;2Q
public void setCountId(int countIds){ OxmlzQ"vM
this.countId=countIds; u$Pf.#
} w>9H"Q[
public String getCountType(){ A^= Hu,"e
return countType; )"i>R
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} :)
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public int getCountId(){ n8;G,[GM80
return countId; YfrTvKX
} "x=@,*Bk
} 5w,YBUp
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CountCache.java +lDGr/
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/* SCI-jf3WN
* CountCache.java =xlYQ}-(a
* Z|cTzunp
* Created on 2007年1月1日, 下午5:01 1Hk<_no5
* &]"_pc/>m
* To change this template, choose Tools | Options and locate the template under i}$N&
* the Source Creation and Management node. Right-click the template and choose ./BP+\)lO
* Open. You can then make changes to the template in the Source Editor. I%zo>s6
*/ [pC-{~
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package com.tot.count; 43orR !.Z
import java.util.*; _uy5?auQ
/** %;B(_ht<-w
* Ygkd~g
* @author ~A:;?A'.
*/ YRM6\S)py
public class CountCache { g:HbmXOBpj
public static LinkedList list=new LinkedList(); $Zu4tuXA
/** Creates a new instance of CountCache */ L[[H\
public CountCache() {} ]TTJr C:
public static void add(CountBean cb){ 0or6_y6
if(cb!=null){ dn.c#,Y
list.add(cb); b09#+CH?
} I;":O"ij\
} l<)JAT;P
} x+)hL
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CountControl.java 4S{l>/I
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/* *!7SM7
* CountThread.java \8>N<B)
* B=RKi\K6a
* Created on 2007年1月1日, 下午4:57 C6T 9
* t"74HZO>
* To change this template, choose Tools | Options and locate the template under @}rfY9o'
* the Source Creation and Management node. Right-click the template and choose K?9H.#(
* Open. You can then make changes to the template in the Source Editor. GL0' :LsZ
*/ |sZ9/G7
CPCB!8-5
package com.tot.count; V:"\(Y
import tot.db.DBUtils; $}h_EI6hS
import java.sql.*; pcxl2I
/** r'JK$9
* f.xSr!
* @author TX5/{cHd
*/ 1p5q}">z
public class CountControl{ v_F?x!
private static long lastExecuteTime=0;//上次更新时间 ~(doy@0M
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 P9HPr2
/** Creates a new instance of CountThread */ %^@0tT
public CountControl() {} B(vz$QE,$r
public synchronized void executeUpdate(){ oIR%{`3"I
Connection conn=null; f*H}eu3/j
PreparedStatement ps=null; O7_NXfh|
try{ $/(/v?3][e
conn = DBUtils.getConnection(); #(}_2x5
conn.setAutoCommit(false); )da8Ru
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Hn2Q1lF-ip
for(int i=0;i<CountCache.list.size();i++){ oTa+E'q
CountBean cb=(CountBean)CountCache.list.getFirst(); KqIe8bi^G
CountCache.list.removeFirst(); r3lr`s`
ps.setInt(1, cb.getCountId()); ea;c\84_N
ps.executeUpdate();⑴ O#Ax P}
//ps.addBatch();⑵ z&G3&?Z
}
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//int [] counts = ps.executeBatch();⑶ o+23?A~+
conn.commit(); o\YdL2:X
}catch(Exception e){ $fpDABf
e.printStackTrace(); leqSS}KU+
} finally{ /|^^v DL
try{ H_$f
v_
if(ps!=null) { WQ`P^5e
ps.clearParameters(); 6B P%&RL
ps.close(); KD<`-b)7<
ps=null; \A"a>e
} #z5?Y2t7~^
}catch(SQLException e){} TgG)btQ
DBUtils.closeConnection(conn); sSb&r
} -PuVI5L<
} !f[N&se
public long getLast(){ ^g"6p#S=n
return lastExecuteTime; ,(b~L<zN&
} i;
uM!d}
public void run(){ ApB'O;5
long now = System.currentTimeMillis(); dKG<"
if ((now - lastExecuteTime) > executeSep) { iFT3fP'> 5
//System.out.print("lastExecuteTime:"+lastExecuteTime); C/#/F#C
//System.out.print(" now:"+now+"\n"); N^j''siB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h v+i{Z9!]
lastExecuteTime=now; ov}{UP]a?
executeUpdate(); BbhdGFG1
} J8[Xl.
else{ +PD5pr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4ov~y1Da)
} ?|F;x"
} wn.0U
}
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//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 ^E8Hv
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类写好了,下面是在JSP中如下调用。 .h }D%Qa
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<% 0
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CountBean cb=new CountBean(); \%*y+I0>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {=Y&q~:8v
CountCache.add(cb); t38T0Ao
out.print(CountCache.list.size()+"<br>"); MYm6C;o$
CountControl c=new CountControl(); ;#Nci%<J\
c.run(); kF7Al]IgT
out.print(CountCache.list.size()+"<br>"); L 32ki}2
%>