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: -0pAj}_2}
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CountBean.java S,Y\ox-
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/* \J]qd4tF
* CountData.java } "QV{W
* EbG`q!C
* Created on 2007年1月1日, 下午4:44 G@Jl4iHug"
* [I
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* To change this template, choose Tools | Options and locate the template under S,I|8
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* the Source Creation and Management node. Right-click the template and choose `E @TPdu
* Open. You can then make changes to the template in the Source Editor. u~JCMM$
*/ hxt,%al
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package com.tot.count; WTlR>|Zdn
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/** 28u3B2\$
* d9@Pze">e
* @author <1^\,cI2
*/ ;+86q"&n
public class CountBean { DK\Ud6w
private String countType; *x0nAo_n
int countId; s":\>
/** Creates a new instance of CountData */ MQ~OG9.
public CountBean() {} } `X.^}oe
public void setCountType(String countTypes){ ,McwPHEMB
this.countType=countTypes; c8R#=^ DD
} 0$saDmED
public void setCountId(int countIds){ fo$5WTY
this.countId=countIds; $e99[y@
} >vr!3
public String getCountType(){ Or({|S9d2
return countType; {? a@UUvC
} @bkZ< Gq
public int getCountId(){ %.NOQ<@W
return countId; ITUwIpAE
} <B3v4f
} /,tQdD&
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CountCache.java 7 3 Oo;
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/* 1u%e7
* CountCache.java 834E
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* @)R6!"p
* Created on 2007年1月1日, 下午5:01 Uk2U:
* L`iC?<}
* To change this template, choose Tools | Options and locate the template under O8!> t7x
* the Source Creation and Management node. Right-click the template and choose (toN??r
* Open. You can then make changes to the template in the Source Editor. @,=E[c
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*/ Q')0 T>F-
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package com.tot.count; {9/ayG[98
import java.util.*; U\<8}+x
/** &EZq%Sd
* W7sx/O9
* @author +"~~;J$
*/ }3}{} w0Y
public class CountCache { \!]Zq#*kH
public static LinkedList list=new LinkedList(); 4R;6u[a]u
/** Creates a new instance of CountCache */ ``Yw-|&:Ae
public CountCache() {} ]>:LHW
public static void add(CountBean cb){ Q5!"tF p
if(cb!=null){ qGH
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list.add(cb); +WxZB
} =P,h5J
} XBTtfl
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} {H\(H_X
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CountControl.java i&%/]Nq
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/* _&]B
* CountThread.java ,hggmzA~
* N~Kl{">`
* Created on 2007年1月1日, 下午4:57 SLj2/B0
* x|TLMu=3=
* To change this template, choose Tools | Options and locate the template under qh40nqS;9
* the Source Creation and Management node. Right-click the template and choose fw[Z7`\Q5
* Open. You can then make changes to the template in the Source Editor. `.0WK
*/ 8M"0o}wx
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package com.tot.count; |q(
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import tot.db.DBUtils; [r)Hm/_=|U
import java.sql.*; 0_A|K>7
/** oD@~wcMIT0
* o1d ECLQa
* @author vz~QR i*
*/ J7p'_\
public class CountControl{ pOe"S
private static long lastExecuteTime=0;//上次更新时间 2#^@awJ ?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )`*=P}D
/** Creates a new instance of CountThread */ ['G@`e*\
public CountControl() {} hxedQvW
public synchronized void executeUpdate(){ 9q4%s?)j
Connection conn=null; O6P{+xj$
PreparedStatement ps=null; QoU0>p+2
try{ NI1jJfH|l
conn = DBUtils.getConnection(); 9"jhS0M
conn.setAutoCommit(false); Kt 0
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ipIexv1/S
for(int i=0;i<CountCache.list.size();i++){ 8}Qmhm`_j=
CountBean cb=(CountBean)CountCache.list.getFirst(); nWyn}+C-
CountCache.list.removeFirst(); ]P5|V4FXo
ps.setInt(1, cb.getCountId()); ]csfK${
ps.executeUpdate();⑴ t/3t69 \x
//ps.addBatch();⑵ YpGG^;M$
} tbNIl cAWS
//int [] counts = ps.executeBatch();⑶ 3~r>G
conn.commit(); NJe^5>4`
}catch(Exception e){ G(;C~kHX
e.printStackTrace(); h VQj$TA
} finally{ \?|FB~.Ry
try{ sXpA^pT"T
if(ps!=null) { 65~X!90k
ps.clearParameters(); $v6`5;#u
ps.close(); X=W.{?
ps=null; #cZ<[K q6
} ly8IrgtKy
}catch(SQLException e){} ;mi+[`E
DBUtils.closeConnection(conn); Oh|KbM*vS
} |#)S`Ua1
} 1U/ dc.x5
public long getLast(){ %]iDhXLr
return lastExecuteTime; g aq"+@fH
} c(R=f+
public void run(){ k4AF
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long now = System.currentTimeMillis(); Pf 4b/w/
if ((now - lastExecuteTime) > executeSep) { MoFAQe
//System.out.print("lastExecuteTime:"+lastExecuteTime); tr<iFT}C
//System.out.print(" now:"+now+"\n"); XITh_S4fs=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); SGp}(j>
lastExecuteTime=now;
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executeUpdate(); 15 /lX
} \QZ~w_
else{ {zri6P+s
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); pI>[^7
} Q.$|TbVfds
} v'vYNh
} &t1Uk[
//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 saj%[Gsy
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类写好了,下面是在JSP中如下调用。 y>5??q
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<% B F,8[|%#
CountBean cb=new CountBean(); BSMM3jXb
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); whoQA}X>
CountCache.add(cb); @C?.)#
out.print(CountCache.list.size()+"<br>"); OX
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CountControl c=new CountControl(); *?-,=%,z/
c.run(); 4|]0%H~n6
out.print(CountCache.list.size()+"<br>"); bS!4vc1`2
%>