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: 0Rme}&$
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CountBean.java ,X&(BQj h
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/* XDot3)2`
* CountData.java voD0u
* >h[ {_+
* Created on 2007年1月1日, 下午4:44 MPn
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* $69ef[b
* To change this template, choose Tools | Options and locate the template under m^9[k,;K
* the Source Creation and Management node. Right-click the template and choose [pc6!qhDG&
* Open. You can then make changes to the template in the Source Editor. W@T_-pTCjK
*/ hDP&~Mk
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package com.tot.count; A3!xYG=+
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/** OLl?1
* Dd=iYMm7
* @author aS7%x>.A!
*/ x+X^K_*
public class CountBean { W=$cQ(x4Z
private String countType; P+hp'YK1
int countId; #nzVgV]
/** Creates a new instance of CountData */ .Lvg
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public CountBean() {} <+/:}S4w)
public void setCountType(String countTypes){ /.Fvl;!J;
this.countType=countTypes; ,pg\5b
} $PNS`@B
public void setCountId(int countIds){ opQdym
this.countId=countIds; PGj?`y4
} /F3bZ3F
public String getCountType(){ FTA[O.tiG
return countType; |.q K69
} :.K#=ROP
public int getCountId(){ 1Ar6hA
return countId; knPo"GQW
} :We}l;.jQ
} [^J2<\<0
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CountCache.java --32kuF&(
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/* OFyZY@B-C~
* CountCache.java =>_k ;x
* e@GR[0~
* Created on 2007年1月1日, 下午5:01 \N?,6;%xB
* R24ZjbKL
* To change this template, choose Tools | Options and locate the template under (ohza<X;6
* the Source Creation and Management node. Right-click the template and choose <]/z45?
* Open. You can then make changes to the template in the Source Editor. 3 E~d
*/ 0D\b;ju<
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package com.tot.count; EZz`pE
import java.util.*; }EW@/; kC
/** D+y_&+&,t
* fuwv,[m
* @author <gdKuoY
*/ p-6(>,+E[
public class CountCache { /{j")
public static LinkedList list=new LinkedList(); oI!L2
/** Creates a new instance of CountCache */ @ZD/y%e
public CountCache() {} T9c=As_EM
public static void add(CountBean cb){ q,W6wM;,E
if(cb!=null){ *>ilT5q
list.add(cb); L&i _
} t]j4PNzn
} XHN`f#(w
} w(y#{!%+
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CountControl.java upJ|`,G{
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/* gm-m_cB<
* CountThread.java $?dAO}f3O)
* 5:=ECtKi
* Created on 2007年1月1日, 下午4:57 SiM1Go}#
* @_O,0d
g
* To change this template, choose Tools | Options and locate the template under #ilU(39e
* the Source Creation and Management node. Right-click the template and choose lF=l|.c
* Open. You can then make changes to the template in the Source Editor. D>YbL0K>X~
*/ jMT];%$[
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package com.tot.count; !A 6l\_
import tot.db.DBUtils; c1,dT2:=
import java.sql.*; N1O& fMz
/** s`bC?wr5h
* V&'
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* @author =Wl*.%1 b
*/ SSS)bv8m
public class CountControl{ Fe4QWB6\U
private static long lastExecuteTime=0;//上次更新时间 _>/T<Db
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .q>4? +
/** Creates a new instance of CountThread */ ice7J2r_
public CountControl() {} &|:T+LVv$+
public synchronized void executeUpdate(){ zW@OSKq4
Connection conn=null; |?t6h 5Mt"
PreparedStatement ps=null; 4HG@moYn@
try{ l*+"0
conn = DBUtils.getConnection(); <Wn"_Ud=
conn.setAutoCommit(false); F^],p|4f
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); CKAs3",
for(int i=0;i<CountCache.list.size();i++){ Kp|#04]
CountBean cb=(CountBean)CountCache.list.getFirst(); .
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CountCache.list.removeFirst(); H& #Od?
ps.setInt(1, cb.getCountId()); yrDWIU(8;6
ps.executeUpdate();⑴ -V'`;zE6
//ps.addBatch();⑵ yqg&dq
} No\H
QQ
//int [] counts = ps.executeBatch();⑶ [N|/d#
conn.commit(); I82?sQ7
}catch(Exception e){ "4{_amgm&<
e.printStackTrace(); ^UF]%qqOn
} finally{ FmALmS
try{ )8c`o
if(ps!=null) { sFEkxZi<
ps.clearParameters(); "CEy r0h
ps.close(); bw@DcT&,
ps=null; XsldbN^6
} _{EO9s2FG
}catch(SQLException e){} ez2 gy"
DBUtils.closeConnection(conn); nP9@yI*7
} 5(/ 5$u
} ;%1ob f 89
public long getLast(){ BO5gwvyI
return lastExecuteTime; @-z#vJ5Qe{
} QK5y%bTSA
public void run(){ 728}K^7:
long now = System.currentTimeMillis(); 2$D
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if ((now - lastExecuteTime) > executeSep) { 5G~; g
//System.out.print("lastExecuteTime:"+lastExecuteTime); eQk ~YA]K
//System.out.print(" now:"+now+"\n"); E)Z$7;N0x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~&/|J)}
lastExecuteTime=now; K8dlECy
executeUpdate(); ZCQ7xQD
} Jmb [d\ /D
else{ q%4l!gzF3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); LE_1H>
} $*| :A
} :<%q9)aPf`
}
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//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 mm3goIi;Y
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类写好了,下面是在JSP中如下调用。 {cF7h)j
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<% _tfZg /+)
CountBean cb=new CountBean(); Fj9/@pe1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >'i
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CountCache.add(cb); `Z{kJMS
out.print(CountCache.list.size()+"<br>"); fhu-YYJt
CountControl c=new CountControl();
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c.run(); ]P TTI\n
out.print(CountCache.list.size()+"<br>"); >G2o
%>