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: <"{qk2LS1
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CountBean.java be]bZ
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/* F,W~,y
* CountData.java *SU\ABcov
* =mS\i663
* Created on 2007年1月1日, 下午4:44 @e(o129
* Ixb=L(V
* To change this template, choose Tools | Options and locate the template under @mOH"acGn?
* the Source Creation and Management node. Right-click the template and choose k;K)xb[w |
* Open. You can then make changes to the template in the Source Editor. U
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*/ "+kL)]
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package com.tot.count; ii[F]sR\
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/** EYtL_hNp}I
* .aO,8M
* @author Yw4n-0g
*/ $ 7O}S.x
public class CountBean { t[ubn+
private String countType; QS%%^+E2
int countId; nygbt<;?
/** Creates a new instance of CountData */ +o\:d1y
public CountBean() {} ah+~y,Gl
public void setCountType(String countTypes){ C7rNV0.Fq
this.countType=countTypes; U{7w#>V
.
} @Z*W
public void setCountId(int countIds){ pWy=W&0~qf
this.countId=countIds; iq8GrdL"
} u[@l~gwL
public String getCountType(){ +]*zlE\N`
return countType; k.5u
} (U&tt]|
public int getCountId(){ ,F79xx9ufg
return countId; +MR.>"
} hBS.a6u1'd
} x.7]/)
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CountCache.java gRCdY8GH
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/* _7H7
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* CountCache.java Id_2PkIN$~
* -&NN51-d\j
* Created on 2007年1月1日, 下午5:01 9KDEM gCW
* Lx\8Z=
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose Z'4./
* Open. You can then make changes to the template in the Source Editor. Wi*.TWz3
*/ Gr7=:+0n|P
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package com.tot.count; S]bmS6#
import java.util.*; -K
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/** \#f<!R4
* UYk/v]ZA
* @author K?[q%W]%
*/ xDG2ws=@D
public class CountCache { +fC=UAZ
public static LinkedList list=new LinkedList(); @LS@cCC,a
/** Creates a new instance of CountCache */ rX4j*u2u
public CountCache() {} mkYqpD7
public static void add(CountBean cb){ Sm)Ha:[4
if(cb!=null){ 695V3R 7
list.add(cb); ]"t@-PFX<
} x}_]A$nV
} Zo|.1pN
} !ipR$ dM
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CountControl.java Q3
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/* NL!u<6y
* CountThread.java ABQa 3{v
* 9f2UgNqe9
* Created on 2007年1月1日, 下午4:57 +aJ>rR
* F<L
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* To change this template, choose Tools | Options and locate the template under brW :C?}
* the Source Creation and Management node. Right-click the template and choose 3?c3<`TW
* Open. You can then make changes to the template in the Source Editor. 5k`l$mW{
*/ %6t2ohO"
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package com.tot.count; !zkZQ2{Wn
import tot.db.DBUtils; u -;_y='m
import java.sql.*; eIz<)-7:
/** qCljo5Tq'
* E8pB;\Z(
* @author hM;lp1l
*/ qu-B|
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public class CountControl{ C"!gZ8*\!9
private static long lastExecuteTime=0;//上次更新时间 N"" BCh"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4(|cG7>9-
/** Creates a new instance of CountThread */ 23c 8
public CountControl() {} JTr vnA
public synchronized void executeUpdate(){ e4!:c^?
Connection conn=null; 7[> 6i
PreparedStatement ps=null; F$ #U5}Q
try{ ;%<,IdhN
conn = DBUtils.getConnection(); X;i~<Tq
conn.setAutoCommit(false); -*$HddD
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =h0,?]z
for(int i=0;i<CountCache.list.size();i++){ V8rx#H~
CountBean cb=(CountBean)CountCache.list.getFirst(); ;nodjbr,j
CountCache.list.removeFirst(); HkO7R
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ps.setInt(1, cb.getCountId()); $})g?Q
ps.executeUpdate();⑴ x[$z({Yf
//ps.addBatch();⑵ F({HP)9b
} E~]R2!9
//int [] counts = ps.executeBatch();⑶ pi
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conn.commit(); Yzh"1|O
}catch(Exception e){ \HKxh:F'
e.printStackTrace(); EB2w0a5
} finally{ 4)@mSSfn.
try{ WU
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if(ps!=null) { X$ s:>[H
ps.clearParameters(); `(YxI
ps.close(); umiBj)r
ps=null; *M:B\D
} N'^&\@)xiU
}catch(SQLException e){} ) L#i%)+
DBUtils.closeConnection(conn); ZUoxMm
} U*22h` S
} ujlY!-GM
public long getLast(){ 8,C*4y~
return lastExecuteTime; bYEy<7)x
} }T&iewk
public void run(){ Jtr"NS?a]
long now = System.currentTimeMillis(); 4)A#2
if ((now - lastExecuteTime) > executeSep) { ,Wk?I%>
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]j`c]2EuP
//System.out.print(" now:"+now+"\n"); ~:Ll&29i
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SKkUU^\#R`
lastExecuteTime=now; ti
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executeUpdate(); sg$rzT-S4
} Tk5W'p|6f
else{ _F$aUtb%O
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); VU&7P/\f%
} U<DZ:ds?T
} Cj{1H([-
} +VO-oFE |
//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 L&u$t}~)
@cFJeOC|
类写好了,下面是在JSP中如下调用。 czS+<
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<% uTKD 4yig
CountBean cb=new CountBean(); 2QJ{a46}
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dwDcR,z?a
CountCache.add(cb); u*Pibgd<
out.print(CountCache.list.size()+"<br>"); J|~MC7#@q
CountControl c=new CountControl(); ?}kG`q
c.run(); hRUhX[
out.print(CountCache.list.size()+"<br>"); {(r`k;fB
%>