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: *))|ZE6jI
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CountBean.java ;/.Z YTD
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/* _!CH
* CountData.java RjT[y: !
* a/ZfPl0Ns[
* Created on 2007年1月1日, 下午4:44 >7|37a
* `6/7},"9t
* To change this template, choose Tools | Options and locate the template under jcj)9;n=!
* the Source Creation and Management node. Right-click the template and choose Q%a4g
* Open. You can then make changes to the template in the Source Editor. yWuq/J:
*/ s5.2gu|"%
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package com.tot.count; \0$?r4A
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/** LM}si|
* Ud](hp"
* @author >\'yj|
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*/ ~BC5no
public class CountBean { c1`o3gb
private String countType; TsQMwV_h
int countId; G>Q{[m$
/** Creates a new instance of CountData */ <
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public CountBean() {} n;U|7it7
public void setCountType(String countTypes){
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this.countType=countTypes; tua+R_"
} Ii)TCSt9U?
public void setCountId(int countIds){ wv<"W@& 9
this.countId=countIds; 8P .! q
} U;(&!Ei
public String getCountType(){ G`pI{_-e
return countType; EQ28pAZ
} fKfi
public int getCountId(){ {XVSHUtw
return countId; ;23F8M%wH
} /mb| %U]~
} *M="k 1P1
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CountCache.java +m1edPA[
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/* loZfzN&6A
* CountCache.java Na=q(OKN
* ukw'$Yt2
* Created on 2007年1月1日, 下午5:01 N5_v}<CN
* h3:k$`_
* To change this template, choose Tools | Options and locate the template under D526X0
* the Source Creation and Management node. Right-click the template and choose "x{S3v4Rb5
* Open. You can then make changes to the template in the Source Editor. /4|qfF3
*/ FUDMaI
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package com.tot.count; ]?kf;A@
import java.util.*; a}wB7B;,g
/** 6ugBbP +^
* 'j.{o
* @author g$<@!
*/ R}0cO^V
public class CountCache { S^_na]M"4
public static LinkedList list=new LinkedList(); ?0.+DB
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/** Creates a new instance of CountCache */ th]9@7UE,
public CountCache() {} xkX,
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public static void add(CountBean cb){ htjJ0>&
if(cb!=null){ (]ORB0kl
list.add(cb); zn M"P|A
} S\C
} wtY#8'^$&
} lU@ni(69d
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CountControl.java 1:,aFp>qr
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/* MW p^.
* CountThread.java M?_VYK
* 03MB,
* Created on 2007年1月1日, 下午4:57 ZXco5,1
* k -SUp8}g
* To change this template, choose Tools | Options and locate the template under Dr;@)
* the Source Creation and Management node. Right-click the template and choose _uRgKoiy
* Open. You can then make changes to the template in the Source Editor. L<E`~\C'
*/ ?J>^X-z
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package com.tot.count; T-27E$0
import tot.db.DBUtils; hX;xbl
import java.sql.*; r`"
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/** 6OVAsmE
* r:u5+A
* @author }ulFW]A^7
*/ Qd@`jwjS
public class CountControl{ N^)L@6
private static long lastExecuteTime=0;//上次更新时间 qD%Jf4.0j
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &
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/** Creates a new instance of CountThread */ JeiW
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public CountControl() {}
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public synchronized void executeUpdate(){ E9|i:
Connection conn=null; h8n J$jg
PreparedStatement ps=null; ?+51 B-
try{ YncY_Hu
conn = DBUtils.getConnection(); vK|dP3
conn.setAutoCommit(false); >V NMQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); xGz$M@f
for(int i=0;i<CountCache.list.size();i++){ R,tR{| 8
CountBean cb=(CountBean)CountCache.list.getFirst(); wWwY.}j
CountCache.list.removeFirst(); KaOS!e'
ps.setInt(1, cb.getCountId()); HmQuRW
ps.executeUpdate();⑴ Y,?rykRj
//ps.addBatch();⑵ @
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} ji">} -
//int [] counts = ps.executeBatch();⑶ h(>4%hF
conn.commit(); ^f>+5G
}catch(Exception e){ 514;!Q4K
e.printStackTrace(); aN.Phn:
} finally{ c>I^SY(r%
try{ mw.9cDf
if(ps!=null) { JgEpqA12
ps.clearParameters(); qdzc"-gH`
ps.close(); E_-CsL%
ps=null; KbSIKj
} K47W7zR
}catch(SQLException e){} (]rtBeT
DBUtils.closeConnection(conn);
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} c^I_~OwaE
} voCQ_~*)9
public long getLast(){ DN!:Rm uc
return lastExecuteTime; oc>,5 x
} M,:GMO:?a
public void run(){ ?-J\~AXL
long now = System.currentTimeMillis(); w,D(zk$
if ((now - lastExecuteTime) > executeSep) { m ?LOd9
//System.out.print("lastExecuteTime:"+lastExecuteTime); s&z+j%;+o
//System.out.print(" now:"+now+"\n"); A"p7N?|%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s4t>/.;x
lastExecuteTime=now; :rwF5
executeUpdate(); oT.g@kf=H
} k_$w+Q
else{ "<NQ2Vr]5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} KI#),~nS
} <T<?7SE+
} D24@lZ`g~
//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 YWjw`,EA(
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类写好了,下面是在JSP中如下调用。 < JA5.6<=
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CountBean cb=new CountBean(); Fb
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {dhG SM7
CountCache.add(cb); r6QNs1f~.
out.print(CountCache.list.size()+"<br>"); #%Uk}5;-
CountControl c=new CountControl(); !3}vl
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c.run(); O0c#-K.f
out.print(CountCache.list.size()+"<br>");
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