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: pfN(Ae
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CountBean.java o[ 5dR<
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/* RAW;ze*"
* CountData.java ER"69zQg|2
* 8 .%0JJ .3
* Created on 2007年1月1日, 下午4:44 (D>_O$o
* a-NTA
* To change this template, choose Tools | Options and locate the template under #mQ@4k9i
* the Source Creation and Management node. Right-click the template and choose 94tfR$W;-
* Open. You can then make changes to the template in the Source Editor. QH'*MY
*/ a"jE\OZ{+s
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package com.tot.count; <%)vl P#@
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/** f?5>V
* xC)bW,%
* @author <h#*wy:o2
*/ FV^jCseZ
public class CountBean { \|HtE(uCM1
private String countType; )9eIo&Nl
int countId; J M`w6}
/** Creates a new instance of CountData */ 3aqH!?rVU
public CountBean() {} Df6i*Ko|
public void setCountType(String countTypes){ F[ E'R.:
this.countType=countTypes; {)" 3
} MPB[~#:
public void setCountId(int countIds){ D$ds[if$U,
this.countId=countIds; }_+XN"}C
} !^arWH[od
public String getCountType(){ MLDzWZ~}ef
return countType; U)(R4Y6 v
} %-n)L
public int getCountId(){ Nv5^2^Sc=
return countId; <F9-$_m
} _o~ pVBl/
} Wdd}y`lS
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CountCache.java qk& F>6<9*
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/* N3G9o`k
* CountCache.java lSX1|,B7:]
* $?GggP d
* Created on 2007年1月1日, 下午5:01 45yP {+/-Q
* ;$D,w
* To change this template, choose Tools | Options and locate the template under opa/+V3E4
* the Source Creation and Management node. Right-click the template and choose C*Q7@+&
* Open. You can then make changes to the template in the Source Editor. Ca |}i+
*/ 5IU!BQU
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package com.tot.count; gPMR,TU
import java.util.*; VzG|Xtco[
/** )\+Imn
* MIJuJ]U}
* @author :w8{BIUN)
*/ r5j$FwY
public class CountCache { T!jh`;D+
public static LinkedList list=new LinkedList(); xw*e`9vAe
/** Creates a new instance of CountCache */ V!:!c]8F
public CountCache() {} /d&m#%9Up]
public static void add(CountBean cb){ eT%x(P
if(cb!=null){ I9kz)Q o
list.add(cb); J&6p/'UPZ
} 'n|U
} w:zo
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} uEgR>X>
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CountControl.java czRBuo+k+
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/* Tg)F.):
* CountThread.java O?vh]o
* rxp|[>O<
* Created on 2007年1月1日, 下午4:57 h3F559bw/<
* YKe&Ph.
* To change this template, choose Tools | Options and locate the template under s9C^Cy^su
* the Source Creation and Management node. Right-click the template and choose ld(60?z>FH
* Open. You can then make changes to the template in the Source Editor. 6lzjaW5h
*/ !gI0"p?
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package com.tot.count; P#TPI*qw
import tot.db.DBUtils; f`4=Bl&"{
import java.sql.*; rQv5uoD
/** -'c
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* RxP~%oADw
* @author her>L3G-E
*/ bqn(5)% {
public class CountControl{ sm18u-
private static long lastExecuteTime=0;//上次更新时间 @,<jPR.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2D!jVr!
/** Creates a new instance of CountThread */ fDr$Wcd~
public CountControl() {} (H:c80/V
public synchronized void executeUpdate(){ @>2]zMFf
Connection conn=null; vapC5,W"2-
PreparedStatement ps=null; 9swHa
try{ qX}3}TL
conn = DBUtils.getConnection(); XU7to]'K
conn.setAutoCommit(false); +xuv+mo
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); FKL4`GEm
for(int i=0;i<CountCache.list.size();i++){ kO)Y|zQ
CountBean cb=(CountBean)CountCache.list.getFirst(); ;8[VCU:
CountCache.list.removeFirst(); !$98U~L
ps.setInt(1, cb.getCountId()); huqtk4u
ps.executeUpdate();⑴ KY&Lv^1_|
//ps.addBatch();⑵ ~Jf(M^E
} JOuy_n
//int [] counts = ps.executeBatch();⑶ o;c"-^>
conn.commit(); W$]qo|2P
}catch(Exception e){ 8`S1E0s
e.printStackTrace();
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} finally{ pYcs4f!?p
try{ YXo?(T..
if(ps!=null) { [%^0L~:
ps.clearParameters(); 8}yrsF#
ps.close(); ]$#bNt/p
ps=null; l!gX-U%-
} 5v oL@w>
}catch(SQLException e){} 1Z 0Qkd(
DBUtils.closeConnection(conn); pk u\)
} Lvt3S
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} 9'(^Coq
public long getLast(){ T}J)n5U}\
return lastExecuteTime; %KF I~Qk
} |./:A5_h
public void run(){ NcbW"Qv3
long now = System.currentTimeMillis(); X:t?'41m\
if ((now - lastExecuteTime) > executeSep) { ku/vV+&O
//System.out.print("lastExecuteTime:"+lastExecuteTime); `i|!wD,=\
//System.out.print(" now:"+now+"\n"); ,fiV xn Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w
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lastExecuteTime=now; uj)vh
executeUpdate(); .Ao
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} 6 _V1s1F
else{ E4=D$hfq`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Cn=#oE8(A
} L_T+KaQCH
} A1;'S<a
} "%Ief4
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 qYoU\y7
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类写好了,下面是在JSP中如下调用。 W)Mz1v #s
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<% ^d#
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CountBean cb=new CountBean(); tSni[,4Kq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [g`4$_9S
CountCache.add(cb); cjtcEW
out.print(CountCache.list.size()+"<br>"); L{1[:a)']B
CountControl c=new CountControl(); Vo[.^0
c.run(); 'w1ll9O
out.print(CountCache.list.size()+"<br>"); H/*slqL
%>