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: s+m,ASj
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CountBean.java 7/^`y')
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/* DxX333vC
* CountData.java 57:Wh=x
* zyey5Z:7
* Created on 2007年1月1日, 下午4:44 TK"!z(p
* K5(:UIWx
* To change this template, choose Tools | Options and locate the template under h|z{ (v
* the Source Creation and Management node. Right-click the template and choose T^'NC8v
* Open. You can then make changes to the template in the Source Editor. #N"zTW%
*/ ]u~6fknm
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package com.tot.count; CH
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/**
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* }M%U}k]+@
* @author e>"/Uii
*/ Ya$JX(aUe
public class CountBean { ;Kb]v\C:
private String countType; ^'"sFEV7RN
int countId; WR;"^<i9
/** Creates a new instance of CountData */ LeY!A#j
public CountBean() {} &gIDcZ
public void setCountType(String countTypes){ f#9DU}2m
this.countType=countTypes; \gd.Bl
} _Se~bkw?v
public void setCountId(int countIds){ <cTusC<
this.countId=countIds; etbB;!6
} ~c8Z9[QW
public String getCountType(){ Y>eypfK"
return countType; K]q9wR'q
} 'MEO?]Tf.^
public int getCountId(){ ?V|t7^+:
return countId; b.jxkx\nt
} ~$I2{I#W
} [3":7bB 'E
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CountCache.java y7 tK>aD}
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/* +bnz%/v
* CountCache.java Q<]~>cd^
* DkO>?n:-C
* Created on 2007年1月1日, 下午5:01 <&&xt
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* CfFNk "0{
* To change this template, choose Tools | Options and locate the template under _SS6@`X
* the Source Creation and Management node. Right-click the template and choose \qPgQsy4
* Open. You can then make changes to the template in the Source Editor. ?kvc`7>
*/ ?cQ
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package com.tot.count; T""y)%
import java.util.*; J(&a,w>p
/** }^J&D=J5V
* UYu 54`'kg
* @author cpV:y
*/ @=jcdn!\M
public class CountCache { 7QdU|1]
public static LinkedList list=new LinkedList(); E%L]ifA9!
/** Creates a new instance of CountCache */ P<iS7Ys+
public CountCache() {} ^:0NKq\
public static void add(CountBean cb){ 1zE_ SNx
if(cb!=null){ (0%0+vY
list.add(cb); WZ"g:Khw
} .MO"8}]8Z
} w+vYD2a
} d7o~$4h|
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CountControl.java 'ad|@Bh
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/* G7lC'~}
* CountThread.java d OY+| P\
* h[d|y_)f
* Created on 2007年1月1日, 下午4:57 IQK__)
* D_E^%Ea&`
* To change this template, choose Tools | Options and locate the template under K%h83tm+
* the Source Creation and Management node. Right-click the template and choose Q"]C"?
* Open. You can then make changes to the template in the Source Editor. )F;[
*/ 5utMZ>%w_#
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package com.tot.count; E&k{ubcT
import tot.db.DBUtils; 6ju+#]T
import java.sql.*; 45`Gv
/** *(&,&$1K
* z41
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* @author gM|X":j
*/ SJVqfi3A
public class CountControl{ p\e*eV1dxx
private static long lastExecuteTime=0;//上次更新时间 &,':@OQ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g<~[k?~J
/** Creates a new instance of CountThread */ Tr}@fa
public CountControl() {} Rkfr4
public synchronized void executeUpdate(){ O'JH=
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Connection conn=null; 8<u_ wt@
PreparedStatement ps=null; 6.tppAO+
try{ 6USet`#
conn = DBUtils.getConnection(); jr"~
conn.setAutoCommit(false); ]zVe% Wa
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ih1s`CjG
for(int i=0;i<CountCache.list.size();i++){ [_j.pMH/P
CountBean cb=(CountBean)CountCache.list.getFirst(); hIa@JEIt
CountCache.list.removeFirst(); ,2?"W8,
ps.setInt(1, cb.getCountId()); rS9*_-NH
ps.executeUpdate();⑴ M3 8,SH<
//ps.addBatch();⑵ Ai iOs?
} v
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//int [] counts = ps.executeBatch();⑶ avls[Bq
conn.commit(); }vO^%Gd
}catch(Exception e){ KM(U-<<R
e.printStackTrace(); {rOz[E9vm
} finally{ f9u["e
try{ S5RS?ya
if(ps!=null) { iXC/?
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ps.clearParameters(); U^ BB|
ps.close(); O*oL(dk*8L
ps=null;
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} 9!V<=0b/
}catch(SQLException e){} Pw
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DBUtils.closeConnection(conn); iZ[o2Tre
} FQi"OZHq
} RCNqHYR
public long getLast(){ $y=sT({VVe
return lastExecuteTime; ,=>O/!s
} > ^3xBI:Q
public void run(){ cZL"e
long now = System.currentTimeMillis(); _}Jz_RS2`
if ((now - lastExecuteTime) > executeSep) { Yl1@gw7
//System.out.print("lastExecuteTime:"+lastExecuteTime); zEY
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//System.out.print(" now:"+now+"\n"); Y_PCL9G{p
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9>le-}~
lastExecuteTime=now; 7K9+7I&C
executeUpdate(); `Pl=%DR
} `Y.RAw5LrE
else{ A'|W0|R9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :KX/GN!n
} aI|)m8>)X
} A@'):V8_%C
} ika{>hbH
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 >~J_9'gX6
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类写好了,下面是在JSP中如下调用。 ycw'>W3.*
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<% #=t:xEz
CountBean cb=new CountBean(); iG!MIt*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); bz H5Lc {%
CountCache.add(cb); 2~h)'n7Mw
out.print(CountCache.list.size()+"<br>"); Q*$x!q
CountControl c=new CountControl(); TQ@*eoJj
c.run(); J+?xfg
out.print(CountCache.list.size()+"<br>"); \ox:/-[c\<
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