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: L[?nST18%
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CountBean.java
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/* FR
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* CountData.java E *F*nd]K
* w6T[hZ 9
* Created on 2007年1月1日, 下午4:44 &{%MjKJ._
* Ia629gi5s
* To change this template, choose Tools | Options and locate the template under :qKF58W
* the Source Creation and Management node. Right-click the template and choose }q% jO
* Open. You can then make changes to the template in the Source Editor. &]P"48NT
*/ nPcS3!7B#
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package com.tot.count; 'LVn^TB_f&
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/** 6M ^IwE
* Ji;SY{~kv
* @author @}<"N
*/ Q%ruQ#
public class CountBean { vUNisVA
private String countType; 55.;+B5L*
int countId; yN*:.al
/** Creates a new instance of CountData */ o=pt_!i/
public CountBean() {} CqqXVF3
public void setCountType(String countTypes){ R7K!A
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this.countType=countTypes; B?LXI3sQZ
} 25:Z;J>
public void setCountId(int countIds){ x#VyQ[ok
this.countId=countIds; 0$6*o}N%
} *5'.!g('
public String getCountType(){
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return countType; CRFCqmevR
} '\`6ot8
public int getCountId(){ EYL]TeS
return countId; \PpXL*.
} IU@_)I+6
} ?d$"[lKX
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CountCache.java 9)`amhf>
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/* }e 9!xA
* CountCache.java ;54(+5pqx
* 5[C ~wvO
* Created on 2007年1月1日, 下午5:01 n` q2s'Pc
* @mf({Q>
* To change this template, choose Tools | Options and locate the template under aD9rp
V
* the Source Creation and Management node. Right-click the template and choose V/PAi.GZ
* Open. You can then make changes to the template in the Source Editor. GnFs63
*/ B'-I{~'/
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package com.tot.count; fXO_g
import java.util.*; hq#kvvi{f
/** @6 /yu>%
* xCWz\-;
* @author A\z`c
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*/ xjo;kx\y^
public class CountCache { -gS"pE^1
public static LinkedList list=new LinkedList(); jin db#)bz
/** Creates a new instance of CountCache */ #;[Bl=3(
public CountCache() {} @%1IkvJV
public static void add(CountBean cb){ MRfb[p3Cx
if(cb!=null){ ;+ azeW^
list.add(cb); 0VN7/=n|
} zB*euHIqZ
} L@RIZu>ZW+
} @o>EBZ7MS
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CountControl.java )%mg(O8uL
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/* }`xdWY
* CountThread.java dAc ?O-~
*
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* Created on 2007年1月1日, 下午4:57 ^~$\ g]
* oFCgu{\kt
* To change this template, choose Tools | Options and locate the template under ~.^AL}zm_
* the Source Creation and Management node. Right-click the template and choose mdW~~-@H
* Open. You can then make changes to the template in the Source Editor. F";.6%;AC
*/ F; 8*H1
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package com.tot.count; ;au*V5a%
import tot.db.DBUtils; ,zhJY ?sk
import java.sql.*; 2N5`'
/** v4rW2F:X
* :^i^0dC
* @author p[9s<lEh
*/ |mhKI is U
public class CountControl{ eQUe
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private static long lastExecuteTime=0;//上次更新时间 +5!&E7bcd
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `!vUsM .d
/** Creates a new instance of CountThread */ |4;UyHh
public CountControl() {} u.,Q4u|!
public synchronized void executeUpdate(){ .@#A|fgv
Connection conn=null; 6cz/n8M g
PreparedStatement ps=null; _c`K+o"3
try{ <YB9Ac~}z
conn = DBUtils.getConnection(); (YPi&w~S
conn.setAutoCommit(false); "l7NWqfB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aS84n.?vq
for(int i=0;i<CountCache.list.size();i++){ Io n~
CountBean cb=(CountBean)CountCache.list.getFirst(); NBYH;h P
CountCache.list.removeFirst(); x|i_P|Z
ps.setInt(1, cb.getCountId()); k7@t{Cu0D&
ps.executeUpdate();⑴ >Lft9e
//ps.addBatch();⑵ 8`=v.
} 7B7&9<gc
//int [] counts = ps.executeBatch();⑶ w(9*7p p
conn.commit(); ",yc0 2<
}catch(Exception e){ `JB?c
e.printStackTrace(); q_V0+qH
} finally{ PLX>-7@
try{ ,WDX(
if(ps!=null) { NX[4PKJ0C
ps.clearParameters(); v+G=E2Lhv
ps.close(); -F@L}|
ps=null; aC%&U4OS
} .iG&Lw\,
}catch(SQLException e){} kV;fD$iW;
DBUtils.closeConnection(conn); 7fHc[,
} -0Cnp/Yj@
} ~q+hV+fa>
public long getLast(){ +s++7<C
return lastExecuteTime; S >yLqPp
} [ sF(#Y:I
public void run(){ G2Vv i[c
long now = System.currentTimeMillis(); P 43P]M2
if ((now - lastExecuteTime) > executeSep) { cxIk<&i~(
//System.out.print("lastExecuteTime:"+lastExecuteTime); a5YIUVCv
//System.out.print(" now:"+now+"\n"); 424(3-/v;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /,@p\Ae5
lastExecuteTime=now; piy`zc-yu
executeUpdate(); q%Yn;g|_
} up>c$jJ
else{ asHxL!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :,B7-kBw
} X]%itA
} *v
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} EV pi^>M
//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 S35~Cp
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类写好了,下面是在JSP中如下调用。 {vEOn-(7
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<% 1rKy@9
CountBean cb=new CountBean(); M_g?<rK
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /D!;u]
CountCache.add(cb); M{g%cR0
out.print(CountCache.list.size()+"<br>"); */:uV
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CountControl c=new CountControl(); #@HF<'H}mu
c.run(); $+p?Y)h .
out.print(CountCache.list.size()+"<br>"); Gg Jf7ie4
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