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: Bwc_N.w?3
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CountBean.java KG=57=[
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/* :V0sKg|sS
* CountData.java ES)@iM?5
* ]7{
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* Created on 2007年1月1日, 下午4:44 L.s$|%
* /:d6I].
* To change this template, choose Tools | Options and locate the template under msVi3`q~
* the Source Creation and Management node. Right-click the template and choose Qt\^h/zjG
* Open. You can then make changes to the template in the Source Editor. udOdXz6K?
*/ - i#Kpf
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package com.tot.count; jdIAN
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/** gtnu/Q
* af'gk&%
* @author w|1O-k`
*/ Mi} .
public class CountBean { Bm5\*Xd1(
private String countType; 4-?zW
int countId; ^kK% 8 u
/** Creates a new instance of CountData */ @\WeI"^F8
public CountBean() {} ||))gI`3a
public void setCountType(String countTypes){ #}lWM%9Dy
this.countType=countTypes; |s,y/svp
} K: |-s4=
public void setCountId(int countIds){ h])oo:u'/Q
this.countId=countIds; -%dBZW\u2
} DB+oCE<.#
public String getCountType(){ bao"iv~z
return countType; FeNNzV=
} w$Z%RF'p
public int getCountId(){ e^}@X[*'#
return countId; L6"V=^Bq
} kEp{L
} vSy[lB|)24
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CountCache.java <1#hX(Q
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/* S%jW}v';
* CountCache.java )b1X6w[
* J$U_/b.mk
* Created on 2007年1月1日, 下午5:01 )nGH$Mu
* KE6XNG3
* To change this template, choose Tools | Options and locate the template under k;Fxr%
* the Source Creation and Management node. Right-click the template and choose *L~?.9R
* Open. You can then make changes to the template in the Source Editor. nkzH}F=<
*/ Qff.QI,
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package com.tot.count; vY7@1_"
import java.util.*; X}wo$t
/** ]_j={0%
* p=m:^9/
* @author !4T!@"#
*/ B1A:}#
public class CountCache { lL&U
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public static LinkedList list=new LinkedList(); + KaVvf
/** Creates a new instance of CountCache */ g4y&6!g
public CountCache() {} I_ AFHrj
public static void add(CountBean cb){ ];'7~",Y
if(cb!=null){ z8XWp[K
list.add(cb); {.?pl]Zl6
} yp[,WZt
} .%!^L#g
} "}Ikx tee
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CountControl.java BT`g'#O
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/* ia (&$a8X
* CountThread.java ROXa/
* ~uV(/?o%
* Created on 2007年1月1日, 下午4:57 FU(2,Vl
* gLRDd~H
* To change this template, choose Tools | Options and locate the template under Ylyk/
* the Source Creation and Management node. Right-click the template and choose gZiwXb
* Open. You can then make changes to the template in the Source Editor. X:lStO#5
*/ fv@<
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package com.tot.count; 7xFZJ#
import tot.db.DBUtils; lwz\"8
import java.sql.*; a;v4R[lQ
/** F+ 7*SImv6
* +&dkJ 4g[
* @author h?H|)a<^9
*/ $wn0oIuW
public class CountControl{ [k0/ZfFwV
private static long lastExecuteTime=0;//上次更新时间 vvu $8n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 M ziOpraj
/** Creates a new instance of CountThread */ f-634KuP
public CountControl() {} >FKwFwT4D
public synchronized void executeUpdate(){ 80`$F{xcX
Connection conn=null; $}'(%\7"
PreparedStatement ps=null; Zu<S<??Jf
try{ $ai;8)C6
conn = DBUtils.getConnection(); 5^R?+<rd
conn.setAutoCommit(false); X7[gfKGL)N
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J7qTE8 W=
for(int i=0;i<CountCache.list.size();i++){ pTB7k3g
CountBean cb=(CountBean)CountCache.list.getFirst(); t-5Y,}j
CountCache.list.removeFirst(); &r,)4q+
ps.setInt(1, cb.getCountId()); 0OQ*V~>f
ps.executeUpdate();⑴ Ndmw/ae
//ps.addBatch();⑵ T"aE]4_
} T:Ovh.$
//int [] counts = ps.executeBatch();⑶ 7>f"4r_r6<
conn.commit(); u:f.;?
}catch(Exception e){ ksCF"o/@V
e.printStackTrace(); -SfU.XlZl
} finally{ 8O$LY\G
try{ 3m9b
if(ps!=null) { L|}s Z\2!
ps.clearParameters(); [[w |
ps.close(); l^$'6q"
ps=null; $:\`E56\
} 5KDCmw
}catch(SQLException e){} oH!O{pQK}
DBUtils.closeConnection(conn); ,QpFVlPU
} |2%|=
} <5,|h3]-#
public long getLast(){ Fi;H
return lastExecuteTime; ^8A[
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} !%D';wQ,/
public void run(){ vj344B
long now = System.currentTimeMillis(); e(xuy'4r
if ((now - lastExecuteTime) > executeSep) { 3kk^hvB+f
//System.out.print("lastExecuteTime:"+lastExecuteTime); FUlhEH
//System.out.print(" now:"+now+"\n"); Ibu9AwPm
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {~uTi>U
lastExecuteTime=now; fm`V 2'Rm
executeUpdate(); A)V*faD
} 01n132k
else{ Aq*?Q/pV
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :e nR8MS
} <9piKtb|L
} ~#jiX6<I
} 7Xu# |k
//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 ]@ke_'
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类写好了,下面是在JSP中如下调用。 fISK3t/=C
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<% UAT\ .
CountBean cb=new CountBean(); 9cUa@;*1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $A-X3d;'\/
CountCache.add(cb); tpC^68*F
out.print(CountCache.list.size()+"<br>"); V=dOeuYd
CountControl c=new CountControl(); g2m*Q%
c.run(); 0 p?AL=
out.print(CountCache.list.size()+"<br>"); lux
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%>