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: MhI)7jj`mt
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CountBean.java sK%Hx`
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/* 99Yo1Q0
* CountData.java ~d%;~_n
* 7Fi2^DlgX
* Created on 2007年1月1日, 下午4:44 )ClMw!ZrU
* 2vkB<[tSs
* To change this template, choose Tools | Options and locate the template under >6I.%!jU
* the Source Creation and Management node. Right-click the template and choose !UMo4}Y
* Open. You can then make changes to the template in the Source Editor. aR)en{W
*/ V9E6W*IE
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package com.tot.count; x:?a;m uf
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/** Hg9.<|+yo
* _0W;)v
* @author i,IM?+4
*/ p + l_MB
public class CountBean { 3U~lI&
private String countType; O GFE*
int countId; ~`\9Q
/** Creates a new instance of CountData */ xe6_RO%
public CountBean() {} E! I
public void setCountType(String countTypes){ zzfn0g
this.countType=countTypes; 80$0zbw$
} .FKJyzL
public void setCountId(int countIds){ xEiX<lguyN
this.countId=countIds; =`1m-
} -N7xO)
public String getCountType(){ W~u
return countType; f' '{.L
} mUt,Z^ l`
public int getCountId(){ -H4+ur JJ
return countId; =\Vu=I
} O*rmD<L$
} ^V: "zzn&
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CountCache.java L8dU(P
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/* t[?a@S~6
* CountCache.java R#/?AD&
* *vRI)>wU
* Created on 2007年1月1日, 下午5:01 J`r,_)J"2
* {,Bb"0 \
* To change this template, choose Tools | Options and locate the template under L-z;:Ztk
* the Source Creation and Management node. Right-click the template and choose fQQsb 5=i
* Open. You can then make changes to the template in the Source Editor. "X5_-l
*/ 7V} ]C>G
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package com.tot.count; |}M0,AS
import java.util.*; %'"HGZn b
/** <rB3[IJo
* 7!r#(>I6?1
* @author GOf`Z'\xt
*/ p?V?nCv1O
public class CountCache { ~M
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public static LinkedList list=new LinkedList(); d@4rD}_Z
/** Creates a new instance of CountCache */ \TbsoWX
public CountCache() {} +5HnZ?E\
public static void add(CountBean cb){ V#NG+U.B
if(cb!=null){ ~!ZmF(:
list.add(cb); T A\4uy6o
} K$G RJ
} ^qeY9O
} ?GO
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CountControl.java c~^CKgr~R9
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/* |DE%SVZB
* CountThread.java !/j,hO4Z4
* w;
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* Created on 2007年1月1日, 下午4:57 .hX0c"f]b
* V uG?B{
* To change this template, choose Tools | Options and locate the template under Tm)GC_
* the Source Creation and Management node. Right-click the template and choose OJP5k/U$
* Open. You can then make changes to the template in the Source Editor. <b d1
*/ gB>imr#e&
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package com.tot.count; pb^,Qvnp
import tot.db.DBUtils; ]*N:;J
import java.sql.*; V1SqX:;b&
/** >ZT& `E
* OM.k?1%+M
* @author y?pD(u
*/ o"p^/'ri
public class CountControl{ +Edzjf~Tt
private static long lastExecuteTime=0;//上次更新时间 /gz:zThf{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #?{qlgv<p
/** Creates a new instance of CountThread */ <4bz/^
public CountControl() {} j8GY`f#
public synchronized void executeUpdate(){ <S1??
Connection conn=null; -<qxO
PreparedStatement ps=null; :dP~.ZY7
try{ {O^TurbTFA
conn = DBUtils.getConnection(); l{Jt s I
conn.setAutoCommit(false); $Y6I_U
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {L@+(I
for(int i=0;i<CountCache.list.size();i++){ T><{ze
CountBean cb=(CountBean)CountCache.list.getFirst(); ,~4H{{<j
CountCache.list.removeFirst(); X^}A*4j
ps.setInt(1, cb.getCountId()); 'K@-Z]
ps.executeUpdate();⑴ TUh&d5a9H
//ps.addBatch();⑵ ^GMJ~[]
} gmh5
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//int [] counts = ps.executeBatch();⑶ XTJvV
conn.commit(); vS OT*0r
}catch(Exception e){ EgTFwEj
e.printStackTrace(); bfgz1
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} finally{ ao#!7F
try{ OAv>g pw
if(ps!=null) { iF!mV5#
ps.clearParameters(); Sd},_Kh
ps.close(); pDu{e>S|:
ps=null; zfhTc=(/
} .K IVf8)"
}catch(SQLException e){} =/FF1jQ
DBUtils.closeConnection(conn); *E:x E/M!2
} qmZ2d!)o
} }N3V5cab
public long getLast(){ 3bC+Mco
return lastExecuteTime; ><;Q@u5~
} kt^yj"C>
public void run(){ D+Cm<ZT~
long now = System.currentTimeMillis(); 5h0>!0
if ((now - lastExecuteTime) > executeSep) { R A:jzht
//System.out.print("lastExecuteTime:"+lastExecuteTime); ![ZmV
//System.out.print(" now:"+now+"\n"); KP3n^
$~
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x97L6!
lastExecuteTime=now; Lf. 1>s
executeUpdate(); CSL#s^4T
} gv#4#]
else{ Ia2(Km
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); C.~j'5N
} $>*Yhz `
} rH&G<o&,
} aD9rp
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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 79ckLd9
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类写好了,下面是在JSP中如下调用。 AoYaVlKG8
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<% bd!U)b(}OV
CountBean cb=new CountBean(); Cq>6rn
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); < f(?T`
CountCache.add(cb); ak;6z]f8[
out.print(CountCache.list.size()+"<br>"); +\0T\;-Xe
CountControl c=new CountControl(); hSB?@I4s<\
c.run(); 8eluO ?p
out.print(CountCache.list.size()+"<br>"); G"T\=cQz
%>