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: @ 63Uk2{W>
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CountBean.java &3a1(>(7F
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/* xb`,9.a7
* CountData.java ktQMkEj#
* YK(I'
* Created on 2007年1月1日, 下午4:44 ]PlDe8
* ,khB*h14;h
* To change this template, choose Tools | Options and locate the template under t+C9QXY
* the Source Creation and Management node. Right-click the template and choose 72J@Dc
* Open. You can then make changes to the template in the Source Editor. dg#w/}}m
*/ 3/+r*lv>X
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package com.tot.count; ')]K&
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/** xw2dEvjgp%
* jhs('n,
* @author u#TRm?s
*/ v/ dyu
public class CountBean { frB~ajXK
private String countType; v2X>%
int countId; Nr24Rv
/** Creates a new instance of CountData */ ""LCyKu
public CountBean() {} zMZP3
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public void setCountType(String countTypes){ n/ ]<Bc?
this.countType=countTypes; &
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} RY8Ot2DWi
public void setCountId(int countIds){ #Av6BGM|,
this.countId=countIds; QuEfV ?)_4
} CUz1q*):
public String getCountType(){ Snm
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return countType; R.KqTEs<k
} <zmtVE*>g
public int getCountId(){ 0#K?SuY.eN
return countId; ;%u'w;sgq
} +C`h*%BW
} y_aKW4L+
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CountCache.java NI(fJ%U
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/* ^.']-XjC
* CountCache.java :Bk!YK
* '<(S*&s
* Created on 2007年1月1日, 下午5:01 )C
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* %Pl
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* To change this template, choose Tools | Options and locate the template under h!c6]D4!L
* the Source Creation and Management node. Right-click the template and choose w.tQ)x1h
* Open. You can then make changes to the template in the Source Editor. Q<TD5t9
*/ y]1:IJL2;
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package com.tot.count; d=?Kk4Ag
import java.util.*; KC@F"/h`/
/**
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* ",U>;`
* @author Y\CR*om!W
*/ _,S
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public class CountCache { T(<
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public static LinkedList list=new LinkedList(); 8#NI`s*
/** Creates a new instance of CountCache */ qx#k()E.U
public CountCache() {} oH;0_!
public static void add(CountBean cb){ sY @S
if(cb!=null){ ohI>\
list.add(cb); WD"3W)!
} 5f.G^A: _X
} )e,Rp\fY$
} @y)'h]d
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CountControl.java 'g3!SdaLF
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/* S1_X@[t
* CountThread.java v=-8} S
* |~QHCg<
* Created on 2007年1月1日, 下午4:57 -Oj}PGj$e\
* #Y)Gos
* To change this template, choose Tools | Options and locate the template under Z^Y_+)=s
* the Source Creation and Management node. Right-click the template and choose +4[L_
* Open. You can then make changes to the template in the Source Editor. a(!_3i@
*/ ;
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package com.tot.count; P=Au~2X
import tot.db.DBUtils; t:pgw[UJ
import java.sql.*; os=Pr{
/** *-KgU'u?
* cmw2EHTT<
* @author VBHDI{HzRv
*/ v% mAU3M
public class CountControl{ ze%kP#c6!
private static long lastExecuteTime=0;//上次更新时间 `RRC8 ]l
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 #LP38wE
/** Creates a new instance of CountThread */ KY1(yni&8[
public CountControl() {} D%tcYI(
public synchronized void executeUpdate(){ (%\vp**F
Connection conn=null; )v1y
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PreparedStatement ps=null; %RlG~a
try{ +
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conn = DBUtils.getConnection(); I-@A{vvPK
conn.setAutoCommit(false); r9),F.6,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); [K(|V
for(int i=0;i<CountCache.list.size();i++){ *pu ,|
CountBean cb=(CountBean)CountCache.list.getFirst(); };rxpw>ms
CountCache.list.removeFirst(); +/">]QJ
ps.setInt(1, cb.getCountId()); %t*_Rtz\o
ps.executeUpdate();⑴ L|O'X4"&_
//ps.addBatch();⑵ Qktj
} $d<vPpJ3
//int [] counts = ps.executeBatch();⑶ Ek0zFnb[Gx
conn.commit(); QKj8~l(
}catch(Exception e){ dNQR<v\IL
e.printStackTrace(); (k{rn3,
} finally{ ~Y-
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try{ X\?PnD`,
if(ps!=null) { 8M{-RlR
ps.clearParameters(); [2]Ti_
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ps.close(); .XD.'S
ps=null; b^SQCX+P
} ck=x_HB1
}catch(SQLException e){} Dd1\$RBo
DBUtils.closeConnection(conn); i|- 6
} ^A4bsoW
} Ro&s\T+d
public long getLast(){ rQ_!/J[9
return lastExecuteTime; ? {@UB*
} zz4TJ('
public void run(){ Z*9Qeu-N:
long now = System.currentTimeMillis(); H9@24NFb
if ((now - lastExecuteTime) > executeSep) { C'6yt
//System.out.print("lastExecuteTime:"+lastExecuteTime); X(sN+7DOV
//System.out.print(" now:"+now+"\n"); Ec44JD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (\CT
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lastExecuteTime=now; f)~j'e
executeUpdate(); 9-Y.8:A`
} 3M 5+!H
else{ K>!+5A$6i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Q]Kc<[E
} h($XR+!#
} +pGkeZX
} K?M{=$N
//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 17-D\
+}
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类写好了,下面是在JSP中如下调用。 ("G
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<% sZ-A~X@g
CountBean cb=new CountBean(); {P/5cw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /QA:`_</oh
CountCache.add(cb); aan)yP
out.print(CountCache.list.size()+"<br>"); O{4G'CgN(
CountControl c=new CountControl(); $#b@b[h<w
c.run(); :\]TAQd-
out.print(CountCache.list.size()+"<br>"); T^"-;
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