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: 5d> nIKW
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CountBean.java @>+^W&
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/* ;A
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* CountData.java )\RzE[Cb
* ix(U:'{
* Created on 2007年1月1日, 下午4:44 cO8`J&EK
* yB
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* To change this template, choose Tools | Options and locate the template under !?S5IGLOj
* the Source Creation and Management node. Right-click the template and choose FK-}i|di
* Open. You can then make changes to the template in the Source Editor. KSF5)CZ5
*/ G% o7BX
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package com.tot.count; 5<!o{)I
t) ;
/** ^6ExW>K
* PG\\V$}A(
* @author OY+!aG@.
*/ !}z%#$
public class CountBean { )lQN)!.)
private String countType; &
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int countId; Xs{/}wc.q;
/** Creates a new instance of CountData */ f:n] Exsy
public CountBean() {} qK<aZ%V
public void setCountType(String countTypes){ O\LjtMF
this.countType=countTypes; mipi]*ZfXE
} @QvfN>T
public void setCountId(int countIds){ "ugX
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this.countId=countIds; 5JO[+>
} zC<'fT/rG
public String getCountType(){ M|1eqR%x-?
return countType; N5[_a/
} &*X3ch
public int getCountId(){ (PRaiE
return countId; z\X60T
} H?rSP0.
} 7yo|ie@S
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CountCache.java e_YW~z=6t
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/* ON:LPf>"-
* CountCache.java /&~nM
* NvXj6U*%
* Created on 2007年1月1日, 下午5:01 Na~g*)uT$
* +J\L4ri k
* To change this template, choose Tools | Options and locate the template under p*A^0DN'Fn
* the Source Creation and Management node. Right-click the template and choose e}{8a9J<%_
* Open. You can then make changes to the template in the Source Editor. ~,(0h:8
*/ 113Z@F
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package com.tot.count; d)`nxnbMeM
import java.util.*; \9dz&H
/** 9itdRa==
* jrDz7AfA
* @author =g{_^^n
*/ 4v rm&k
public class CountCache { #R~">g:w
public static LinkedList list=new LinkedList(); S/#) :,YS
/** Creates a new instance of CountCache */ MAsWds`bpB
public CountCache() {} u.ULS3`C/X
public static void add(CountBean cb){ k+W
if(cb!=null){ sg'Y4
list.add(cb); >=.ch5h3J)
}
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} |NphG|
} ~EM#Hc,
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CountControl.java |U;w !0
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/* D'HL /[@`
* CountThread.java K8yWg\K
* GV `idFd
* Created on 2007年1月1日, 下午4:57 umq$4}T'$
* z{ Zimr
* To change this template, choose Tools | Options and locate the template under !?tu!
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* the Source Creation and Management node. Right-click the template and choose $i1>?pb3
* Open. You can then make changes to the template in the Source Editor. G#_(7X&
*/ :epitpJ
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package com.tot.count; @j)f(Zlu#
import tot.db.DBUtils; ~FK+bF?%
import java.sql.*; rRF+\cP?.
/** $g}/T_26
* Mt7X<?GZm
* @author #R"9)vHp
*/ 0C4*F
public class CountControl{ IdN%f]=/
private static long lastExecuteTime=0;//上次更新时间 cG~_EX$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 T1g:gfw@
/** Creates a new instance of CountThread */ q\{;_?a
public CountControl() {} ^^j|0qshL
public synchronized void executeUpdate(){ J8`1V`$
Connection conn=null; Q rrZF.
PreparedStatement ps=null; OI;L9\MJc
try{ (_s!,QUe
conn = DBUtils.getConnection(); D9@<#2-
conn.setAutoCommit(false); ~@a) E+LsF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $w2[5|^S
for(int i=0;i<CountCache.list.size();i++){ juve9HaW
CountBean cb=(CountBean)CountCache.list.getFirst(); Aw_R
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CountCache.list.removeFirst(); Px^<2Q%Fs
ps.setInt(1, cb.getCountId()); Yc|-sEK/
ps.executeUpdate();⑴ A61-AwvF8-
//ps.addBatch();⑵ {4V:[*3
} &L[8Mju6
//int [] counts = ps.executeBatch();⑶ B8BY3~}]
conn.commit(); ]% ZjD
}catch(Exception e){ dxae2 tV
e.printStackTrace(); $yR{ZFo
} finally{ @eG#%6">
try{ X~<>K/}u5
if(ps!=null) { 6w .iEb
ps.clearParameters();
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ps.close(); .n^O)|Z
ps=null; `gA5P %
} R, (+NT$
}catch(SQLException e){} ;r2b@x:<_
DBUtils.closeConnection(conn); xr1I8 5kM
} 0lJBtk9wn
} FrE/K_L
public long getLast(){ i >/@]2
return lastExecuteTime; st1M.}
} ;#Crh}~
public void run(){ $7k04e@]
long now = System.currentTimeMillis(); QtO[g
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); }!J/ 9WKgU
//System.out.print(" now:"+now+"\n"); |~T+f&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); l*V72!Mv
lastExecuteTime=now; aV92.Z_Ku
executeUpdate(); 'E4(!H,k
} *<
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else{ N]<~NG:6b
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); F0o18k_"
} Ov{B-zCA
} `b,g2XA
} G@l|u
//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 "p_[A
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类写好了,下面是在JSP中如下调用。 6b1 Uj<
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<% 7zOvoQ}
CountBean cb=new CountBean(); dsft=t8s
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); fSb@7L
out.print(CountCache.list.size()+"<br>"); u{y5'cJ{
CountControl c=new CountControl(); ^,\se9=(
c.run(); H"Em|LX^
out.print(CountCache.list.size()+"<br>"); 0^tJX1L
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