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: S1I.l">P
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CountBean.java -fl6M-CYX
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/* {?5iK1|}K
* CountData.java ,`k&9o7
* XL^05
* Created on 2007年1月1日, 下午4:44 vXRY/Zzj1
* KyfH8Na?
* To change this template, choose Tools | Options and locate the template under 6o7t eX
* the Source Creation and Management node. Right-click the template and choose e).;;0
* Open. You can then make changes to the template in the Source Editor. [!yA#{xl,
*/ &e@)yVLL
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package com.tot.count; :>2wVN&\c
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/** u\L}B!
*
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* @author pm ,xGo2
*/ 8\!E )M|4
public class CountBean { BjsT 9?6W/
private String countType; qSB&Q0T
int countId; J
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/** Creates a new instance of CountData */ *dw.Ug
public CountBean() {} bY=[ USgps
public void setCountType(String countTypes){ R-j*fO}
this.countType=countTypes; GPK\nz}
} 1*Pxndt&
public void setCountId(int countIds){ |[IyqWG9
this.countId=countIds; C_kuW+H
} } P ,"
public String getCountType(){ z&tC5]#
return countType; @;tfHoXD
} (=Cb)/s0
public int getCountId(){ T" W<l4i-
return countId; +IWH7 qRtp
} #YYJ4^":k
} ~cCMLK em
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CountCache.java e5>'H!)
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/* "H).2{3(x
* CountCache.java fDf[:A,8
* DJL.P6 -W
* Created on 2007年1月1日, 下午5:01 $VvgzjrH
* 'v~'NWfd
* To change this template, choose Tools | Options and locate the template under PnA{@n\
* the Source Creation and Management node. Right-click the template and choose JRo/ HY+
* Open. You can then make changes to the template in the Source Editor. v/q-{1
*/ ,;6 V=ok
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package com.tot.count; [jzsB:;XB&
import java.util.*; O*~z@"\
/** ;na%*G`
* < ,*\t
* @author {g<D:"Q
*/ Z|uvrFa
public class CountCache { 31a,i2Q4
public static LinkedList list=new LinkedList(); B5;%R01A
/** Creates a new instance of CountCache */ d"9tP&
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public CountCache() {} M}x%'=Pox
public static void add(CountBean cb){ **Ioy+
if(cb!=null){ hr
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list.add(cb); GXVx/)H
} vTO9XHc E
} );7
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} )N&SrzqTK
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CountControl.java ORs:S$Nt$
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/* BB/wL_=:
* CountThread.java i D IY|
* I?3b}#&V9
* Created on 2007年1月1日, 下午4:57 KFd
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* 7Ed0BJTa
* To change this template, choose Tools | Options and locate the template under 112WryS
* the Source Creation and Management node. Right-click the template and choose qjP~F
* Open. You can then make changes to the template in the Source Editor. W^tD6H;
*/ '"
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package com.tot.count; S} m=|3%y
import tot.db.DBUtils; vn^O m-\
import java.sql.*; G<$:[ +w
/** @-!P1]V|
* #:gd9os :
* @author )=[\Yf K
*/ T(D6'm:X
public class CountControl{ @(sz "
private static long lastExecuteTime=0;//上次更新时间 <eG| `
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1_]X
/** Creates a new instance of CountThread */ \%a0Lp{ I
public CountControl() {} 89FAh6u E
public synchronized void executeUpdate(){ Xxg|01
Connection conn=null; V/ G1C^'/
PreparedStatement ps=null; 73cb1kfPd
try{ [`\VgKeu
conn = DBUtils.getConnection(); AOR?2u
conn.setAutoCommit(false); i<^X z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y\]ZIvTSb
for(int i=0;i<CountCache.list.size();i++){ )}@D\(/@
CountBean cb=(CountBean)CountCache.list.getFirst(); ~v;I>ij
CountCache.list.removeFirst(); nHdQe
ps.setInt(1, cb.getCountId()); XHk"nbj
ps.executeUpdate();⑴ xpR`fq
//ps.addBatch();⑵ 1&=)Bxg4
} Ek)drt7cy
//int [] counts = ps.executeBatch();⑶ t{]Ew4Y4%O
conn.commit(); U6M~N0)Yr
}catch(Exception e){ ;
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e.printStackTrace(); U#[&(
} finally{ 1!v{#w{u7
try{ !/XNp QP
if(ps!=null) { !<p,G`r
ps.clearParameters(); pWV_KS
ps.close(); d?*]/ZiR
ps=null; PEf yHf7`
} >a?Bk4w
}catch(SQLException e){} v1OVrk>s>
DBUtils.closeConnection(conn); ="voJgvw
} Tz @=N] D
} J?8Mo=UZz
public long getLast(){ BIWe Hx
return lastExecuteTime; d+q],\"R
} duY?LJ @g
public void run(){ {cXr!N^K
long now = System.currentTimeMillis(); &>JP.//spi
if ((now - lastExecuteTime) > executeSep) { oP`l)`
//System.out.print("lastExecuteTime:"+lastExecuteTime); GTP'js
//System.out.print(" now:"+now+"\n"); 6'Q{xJe?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <L-F3Buu
lastExecuteTime=now; x6UXd~
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executeUpdate(); SOOVUMj
} u<ed O+
else{ WO qDW~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); a2Ak?W1
} -l= 4{^pK
} w|9 >4
} "2cOS PpQL
//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 FH,]'
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类写好了,下面是在JSP中如下调用。 7iP+!e}$.
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<% h9)S&Sk{s
CountBean cb=new CountBean(); ybBmg'198
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); {18hzhs
CountCache.add(cb); >w
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out.print(CountCache.list.size()+"<br>"); k>($[;k|b
CountControl c=new CountControl(); (P|[<Sd
c.run(); G4cgY|71
out.print(CountCache.list.size()+"<br>"); i0=U6S:#
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