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: \MQ|(
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CountBean.java =:mD)oX*
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/* ^rjICF e
* CountData.java Uaj8}7v
* *^ncb,1+i
* Created on 2007年1月1日, 下午4:44 $`x4|a8-
* WMZ&LlB%
* To change this template, choose Tools | Options and locate the template under BdB/`X*
* the Source Creation and Management node. Right-click the template and choose )U e9:e
* Open. You can then make changes to the template in the Source Editor. >y"V%
*/ aGx`ec*t
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package com.tot.count; Jj_E/c"
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/** I0sd%'Ht?
* Hq"i0Xm
* @author { :'#Ts<
*/ `$SX%AZA
public class CountBean { )FGm5-K@
private String countType; !]7Z),s
int countId; ko*Ir@SDv
/** Creates a new instance of CountData */ U-#wFc2N
public CountBean() {} I0.{OJ-
public void setCountType(String countTypes){ SaMg)s~B
this.countType=countTypes; Ly/"da
} nJY#d;
public void setCountId(int countIds){ O8"kIDr-
this.countId=countIds; L+7L0LbNU
}
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public String getCountType(){ Ey A}
return countType; uj,YCJ8UZs
} *KN ' 0Z@W
public int getCountId(){ ZGf R:a)wc
return countId; 3|8\,fO?
} Z\D!'FX
} LJ`*&J
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CountCache.java (e6JI]tz{
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/* i[sHPEml(5
* CountCache.java xCz(qR
* _@;t^j+l
* Created on 2007年1月1日, 下午5:01 K[PH#dF5,x
* UUc{1"z{
* To change this template, choose Tools | Options and locate the template under R$k4}p
* the Source Creation and Management node. Right-click the template and choose _Je<_pl!D
* Open. You can then make changes to the template in the Source Editor. BSYJ2
*/ &eKnLGKD
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package com.tot.count; v8W .84e-
import java.util.*; @
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/** [KMW*pA7
* *,q ?mO
* @author C;];4[XR
*/ d5T M_C
public class CountCache { ~CCRs7V/L
public static LinkedList list=new LinkedList(); 1p=^I'#
/** Creates a new instance of CountCache */ AX,V*
s
public CountCache() {} 3Cmbt_WV
public static void add(CountBean cb){ Z5/^pyc
if(cb!=null){ <]xGd!x$
list.add(cb); _>+!&_h
} q@8Jc[\d
} N]udZhkn
} AE? 0UVI
/ E}L%OvE
CountControl.java +XCLdf}dC
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/* uMKO^D
* CountThread.java :6~Nq/hZB
* I },.U&r
* Created on 2007年1月1日, 下午4:57 #pO=\lJ,
* $_ IvzbOh
* To change this template, choose Tools | Options and locate the template under 89o&KF]
* the Source Creation and Management node. Right-click the template and choose Fv$5Zcf
* Open. You can then make changes to the template in the Source Editor. &~)PB
|
*/ Evu`e=LaG
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package com.tot.count; FFX-kS
import tot.db.DBUtils; k%Dpy2uH
import java.sql.*; wd*8w$\
/** uNSaw['0j
* p)v|t/7
* @author djJD'JL
*/ ?_)b[-N!
public class CountControl{ [Z9
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private static long lastExecuteTime=0;//上次更新时间 Tq{+9+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dZ}gf}.v
/** Creates a new instance of CountThread */ `Cq&;-u
public CountControl() {} g<U\7Vp\1
public synchronized void executeUpdate(){ NU[{ANbl
Connection conn=null; ._'AJhU$0
PreparedStatement ps=null; :0N}K}
try{ VZuluV
conn = DBUtils.getConnection(); !*Ex}K99
conn.setAutoCommit(false); E| eEAa
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); BV)oF2b:
for(int i=0;i<CountCache.list.size();i++){ q_iPWmf
p*
CountBean cb=(CountBean)CountCache.list.getFirst(); <8;SSdoKi
CountCache.list.removeFirst(); !2L?8oP-z
ps.setInt(1, cb.getCountId()); N~NUBEKcp
ps.executeUpdate();⑴ 9#(Nd, m})
//ps.addBatch();⑵ 1%Hc/N-
} jHjap:i`cI
//int [] counts = ps.executeBatch();⑶ Nl/^ga
conn.commit(); xb{G:v
}catch(Exception e){ cG!\P: re
e.printStackTrace(); R|&jvG=|
} finally{ H.ha}0J
try{ g{PEplk
if(ps!=null) { M;2@<,rM
ps.clearParameters(); |)~t^
ps.close(); eka<mq|W
ps=null; -)N,HAM>
} FK;3atrz
}catch(SQLException e){} ,GOH8h
DBUtils.closeConnection(conn); PU8>.9x
} u%m,yPU~B
} RfoEHN
public long getLast(){ j-]`;&L
return lastExecuteTime; 7pPaHX8
} h;TN$ /
public void run(){ -sjyv/%_
long now = System.currentTimeMillis(); )LC"rSNx%
if ((now - lastExecuteTime) > executeSep) { /=5:@
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^]rPda#
//System.out.print(" now:"+now+"\n"); |WP}y-Au
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Xz,fjKUnN
lastExecuteTime=now; Lf0X(tC
executeUpdate(); tuK2D,6
} U80h0t%
else{ `:b*#@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vJ,r}$H3
} I<+EXH%1,
} lKdd3W"o
} h~EGRg
//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 '[WVP=M<XV
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类写好了,下面是在JSP中如下调用。 x-nO; L-2p
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<% j_3`J8WwF
CountBean cb=new CountBean(); hs^K9Jt
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); WUBI(g\
CountCache.add(cb); :+ZLKm
out.print(CountCache.list.size()+"<br>"); 8
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CountControl c=new CountControl(); xeNj@\jdC5
c.run(); NHaY&\
out.print(CountCache.list.size()+"<br>"); <aQ<Wy=\
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