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: :23w[vt=
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CountBean.java LldZ"%P
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{
/* |#G.2hMFr
* CountData.java tGv5pe*r
* ,xmmS\
* Created on 2007年1月1日, 下午4:44 0<Q['l4Ar
* ([\mnL<FC
* To change this template, choose Tools | Options and locate the template under \2F{r<A\@
* the Source Creation and Management node. Right-click the template and choose 91'i7&~xdG
* Open. You can then make changes to the template in the Source Editor. 3VNYDY`>
*/ VrDSN
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package com.tot.count; L[;U
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/** l12Pj02 w
* 3[`/rg,
* @author H&0dc.n~.
*/ tbMf_-g
public class CountBean { ?}p~8{ '
private String countType; gp@X(d
int countId; R|4a9G
/** Creates a new instance of CountData */ o3C7JG
public CountBean() {} X+6`]]
public void setCountType(String countTypes){ 39Nz>Nu:
this.countType=countTypes; y~eQVnH5W
} jUnS&1]MF
public void setCountId(int countIds){ 02+ k,xFb
this.countId=countIds; Jc8^m0_
} .tRp
public String getCountType(){ m/M=.\]
return countType; CYkU-
} Y
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public int getCountId(){ LTsX{z
return countId; XR2Gw4]
} (x)}k&B;
} *GUQz
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CountCache.java 6b!F7kyg
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/* 9x4%M&<Z9a
* CountCache.java }.ZT?p\
* VK)vb.:
* Created on 2007年1月1日, 下午5:01 ]{.iv_I
* &7-ENg9 [
* To change this template, choose Tools | Options and locate the template under zeqwmV=
* the Source Creation and Management node. Right-click the template and choose 3rdrNc
* Open. You can then make changes to the template in the Source Editor. ^$>Q6.x?*)
*/ %?sPKOh3N}
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package com.tot.count; m[>pv1o
import java.util.*; :ebu8H9f%
/** p+.xye U(
* 4`X]$.
* @author eE=}^6)(*
*/ LdH23\
public class CountCache { D(X:dB50@
public static LinkedList list=new LinkedList(); J=l\t7w
/** Creates a new instance of CountCache */ `T#Jiq E
public CountCache() {} &eA!h
public static void add(CountBean cb){ $*\GZ$y>
if(cb!=null){ fK
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list.add(cb); c'!+]'Lr
} 9M]%h
} \Bvy~UeE)>
} D!g\-y
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CountControl.java IE*5p6IM~
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/* J/k4CV*li(
* CountThread.java W Te1E, M
* t&>eZ"
* Created on 2007年1月1日, 下午4:57 )k~{p;Ke
* B]nu \!
* To change this template, choose Tools | Options and locate the template under O>c2*9PM
* the Source Creation and Management node. Right-click the template and choose oC
}
* Open. You can then make changes to the template in the Source Editor. (~Hwq:=.
*/ uQmtd
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package com.tot.count; _(_U=
import tot.db.DBUtils; 8mnzxtk
import java.sql.*; gw^X -
/** D/`b~Yl
* ?l?_8y/ww
* @author e_h`x+\:
*/ d%lwg~@&|5
public class CountControl{ [+3~wpU(p
private static long lastExecuteTime=0;//上次更新时间 *7`amF-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 "8R\!i.
/** Creates a new instance of CountThread */ Yw6d-5=:
public CountControl() {} XTKAy;'5
public synchronized void executeUpdate(){ X B[C&3I
Connection conn=null; # n\|Q\W
PreparedStatement ps=null; q6T>y%|FZ
try{ , 9"A"p*R
conn = DBUtils.getConnection(); 0N`'a?x
conn.setAutoCommit(false); KrqO7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); s g6e%
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for(int i=0;i<CountCache.list.size();i++){ &m~
CountBean cb=(CountBean)CountCache.list.getFirst(); w<me(!-'
CountCache.list.removeFirst(); a-Ne!M[
ps.setInt(1, cb.getCountId()); @D2KDV3'
ps.executeUpdate();⑴ [W--%=Ou
//ps.addBatch();⑵ $E35W=~)
} tK LAA+Z
//int [] counts = ps.executeBatch();⑶ ibxtrt=
conn.commit(); Y6ORI
}catch(Exception e){ 12 S[m~L%
e.printStackTrace(); v>'mW
} finally{ *rmwTD"
try{ />[~2d
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if(ps!=null) { =G-u "QJ6
ps.clearParameters(); A,f%0
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ps.close(); /GU%{nT
ps=null; Sp~gY]:
} od`:w[2\
}catch(SQLException e){} (IIOVv
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DBUtils.closeConnection(conn); mqv!"rk'w
} }c;h:CE#
} ]zR,Y=
#
public long getLast(){ [.*o<
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return lastExecuteTime; 90]{4 ]y;
} Rss=ihlM
public void run(){ SPY4l*kX
long now = System.currentTimeMillis(); cwKOE?!
if ((now - lastExecuteTime) > executeSep) { @V5'+^O
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ykt(%2L
//System.out.print(" now:"+now+"\n"); ]J6+nA6)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "Qxn}$6-
lastExecuteTime=now; 5jBBk*/\
executeUpdate(); i4*!t.eI
} n:5*Tg9
else{ hR3Pa'/i
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); K#],4OG
} +gsk}>"
} oO)KhA?y
} #p^r)+\3=
//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 uyDYS
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类写好了,下面是在JSP中如下调用。 dwt<s[k
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<% gZ1|b
CountBean cb=new CountBean(); /,Sd
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q`X5W
CountCache.add(cb); JI}p{yI
out.print(CountCache.list.size()+"<br>"); R(sa.Q\D4
CountControl c=new CountControl(); G
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c.run(); X@7K#@5
out.print(CountCache.list.size()+"<br>"); AFcA5:ja
%>