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: OlW5k`B
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CountBean.java ?6[u\V
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/* A8nf"mRD:
* CountData.java j}%C;;MPH
* (:#4{C
* Created on 2007年1月1日, 下午4:44 W}^>lM\8
* on\ahk, y]
* To change this template, choose Tools | Options and locate the template under B`%%,SLJ
* the Source Creation and Management node. Right-click the template and choose L@ N\8mf
* Open. You can then make changes to the template in the Source Editor. Qmv8T
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*/ :$^sI"hO
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package com.tot.count; }N3Ur~X\
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/** I}
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* oM}P Wf-
* @author t2-bw6U
*/ Ga"<qmLMc
public class CountBean { Zg;Ht
private String countType; bu\D*-
int countId; g;nPF*(
/** Creates a new instance of CountData */ ?P2d
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public CountBean() {} `t#Ie*
public void setCountType(String countTypes){ sgeME^ v
this.countType=countTypes; @aoHz8K
} Q0_|?]v
public void setCountId(int countIds){ {<^PYN>`
this.countId=countIds; '6>nXp?)r
} 4d]T`
public String getCountType(){ 74Il]i1=
return countType; rI1;>/Ir
} ByXcs'
public int getCountId(){ JA?P jo
return countId; WB|SXto%4D
} 1'J|yq
} w5&,AL:
@ GzN0yXhR
CountCache.java /I'
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/* SR1UO'.
* CountCache.java T CO^9RP<
* "IsDL^)A9
* Created on 2007年1月1日, 下午5:01 NB/ wJ3 F
* A!5)$>!o
* To change this template, choose Tools | Options and locate the template under Z}6H529[
* the Source Creation and Management node. Right-click the template and choose }"9jCxXL
* Open. You can then make changes to the template in the Source Editor. L}U fd >*
*/ W-U[7n
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package com.tot.count; uw&'=G6v
import java.util.*; )e:u 6]
/** uJHf6Ye
* YR/rN,
* @author n&uD=-
*/ @k2nID^>
public class CountCache { \c$!C8z
public static LinkedList list=new LinkedList(); 8|p*T&Cn&
/** Creates a new instance of CountCache */ (/l9@0Y.t
public CountCache() {} =C2,?6!
public static void add(CountBean cb){ TL_8c][.4$
if(cb!=null){ ijWn,bj
list.add(cb); ,U/ZG|=v
} oBTRO0.s+
} ul3._Q
} h3Z0NJ=xM
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CountControl.java \lpR+zaF
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/* U ()36
* CountThread.java -^LEGKN
* H<YS2Ed
* Created on 2007年1月1日, 下午4:57 s4c2
* PYz^9Ud 6g
* To change this template, choose Tools | Options and locate the template under ra k@oW]
* the Source Creation and Management node. Right-click the template and choose kC)ye"r
* Open. You can then make changes to the template in the Source Editor. VDq?,4Kb
*/ 7*r7Q'
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package com.tot.count; LHz-/0[
import tot.db.DBUtils; HGpj(U:`c
import java.sql.*; "(rG5z3P
/** q\g|K3V)
* <ibEo98
* @author 0X3kVm<
*/ [MKL>\U
public class CountControl{ m [FH>
private static long lastExecuteTime=0;//上次更新时间 Yl#r9TM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 EBN'u&zX
/** Creates a new instance of CountThread */ @9^ozgg
public CountControl() {} mmG+"g$|
public synchronized void executeUpdate(){ ^SKuX?f\
Connection conn=null; HW(cA}$
PreparedStatement ps=null; o4CgtqRs
try{ |,89zTk'
conn = DBUtils.getConnection(); Fh4kd>1D
conn.setAutoCommit(false); a$SGFA}V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 14p <0BG
for(int i=0;i<CountCache.list.size();i++){ fWywegh
CountBean cb=(CountBean)CountCache.list.getFirst(); Zi fAn
CountCache.list.removeFirst(); TPrqb
ps.setInt(1, cb.getCountId()); @<O
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ps.executeUpdate();⑴ u<l[S
//ps.addBatch();⑵ BV X6
} &i,xod6$
//int [] counts = ps.executeBatch();⑶ ;X
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conn.commit(); dk9'C
}catch(Exception e){ }Q?,O
e.printStackTrace(); @e_ bG@
} finally{ j\D_Z{m2
try{ T8,?\7)S9
if(ps!=null) { !giL~}j(R
ps.clearParameters(); O!(M:.
ps.close(); Ph'P<h:V
ps=null; kw>W5tNpf:
} I=)u:l c
}catch(SQLException e){} 0[JJ
DBUtils.closeConnection(conn); Oozt&* F
} YULI
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} `)5E_E3
public long getLast(){ *1fq :--
return lastExecuteTime; #%xzy@`
} 8(euWS
public void run(){ c|%.B2
long now = System.currentTimeMillis(); Ap{p_~~iJ
if ((now - lastExecuteTime) > executeSep) { Y9)uy 8c
//System.out.print("lastExecuteTime:"+lastExecuteTime); %OeA"#
//System.out.print(" now:"+now+"\n"); <0r2m4z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w NlC2is
lastExecuteTime=now; mjDaus59
executeUpdate(); tk@
T-;
} 0wCJNXm
else{ LwV4p6A
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); tO$/|B74Bz
} h|tdK;)
} F(J6 XnQ
} 0L_JP9e
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 O9#8%p%
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类写好了,下面是在JSP中如下调用。 G'oMZb ({=
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<% B 3Y,|*
CountBean cb=new CountBean(); ?32gug\i'}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); yF-EHNNf
CountCache.add(cb); WleE$ ,
out.print(CountCache.list.size()+"<br>"); Nv@SpV'
CountControl c=new CountControl(); :nZVP_d+
c.run(); )_eEM1
out.print(CountCache.list.size()+"<br>"); a7+w)]r
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