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: wEM=Tr/h
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CountBean.java 2/r8%Sq
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/* Sx QA*}N
* CountData.java *|g[Mn
* 2[Lv_<i|
* Created on 2007年1月1日, 下午4:44 *l{epum;
* O+|C<;K
* To change this template, choose Tools | Options and locate the template under n<j+KD#a
* the Source Creation and Management node. Right-click the template and choose Pb>/b\&JS
* Open. You can then make changes to the template in the Source Editor. po*8WSl9c[
*/ 6];3h>c]N
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package com.tot.count; .!KsF
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/** YwET.(oo
* Uzzm2OS`
* @author s$>n U
*/ qjhV/fsfb
public class CountBean { F/BR#J1
private String countType; '7el`Ff
int countId; $'3xl2T
/** Creates a new instance of CountData */ GW;%~qH[,
public CountBean() {} lTqlQ<`V
public void setCountType(String countTypes){ DbH;DcV7
this.countType=countTypes; eIalcBY
} [Cv./hEQi
public void setCountId(int countIds){ uOLShNo
this.countId=countIds; <C&|8@A0
} N4C7I1ihq
public String getCountType(){ Ch>F11kC
return countType; z``wqK
} C$6FI`J
public int getCountId(){ H(
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return countId; *PnO$q@`
} B F<u3p??
} T8z?_ *k
}Cu[x'J
CountCache.java WM
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/* hk4t #Km
* CountCache.java 8i`>],,ch
* ( ~5M{Xh
* Created on 2007年1月1日, 下午5:01 zVw5 (Tc
* \OVtvJV]
* To change this template, choose Tools | Options and locate the template under *C5`LgeX
* the Source Creation and Management node. Right-click the template and choose IB[$~sGe
* Open. You can then make changes to the template in the Source Editor. Pn">fWRCx
*/ \6SjJ]o>
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package com.tot.count; Yu3S3aRE
import java.util.*; 4G(7V:
/** 950N\Y@u
* %|(c?`2|
* @author ;z4F-SYQ
*/ "g^i%
public class CountCache { lfcGi3
public static LinkedList list=new LinkedList(); w7?fJ")
/** Creates a new instance of CountCache */ Gm Wr
public CountCache() {} P+hcj
p*
public static void add(CountBean cb){ ~< bpdI0
if(cb!=null){ H\ejW@<;h
list.add(cb); mfQ#n!{ZH
} Re8x!e'>
} !Rl|o^Vw>{
} NAvR^"I~
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CountControl.java ^)gyKl:E'
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/* |^1U<'oM#
* CountThread.java dyWp'vCQs\
* 4Lt9Dx1
* Created on 2007年1月1日, 下午4:57 1^WGJ"1
* )FQ"l{P
* To change this template, choose Tools | Options and locate the template under @=VxWU
* the Source Creation and Management node. Right-click the template and choose M-"j8:en
* Open. You can then make changes to the template in the Source Editor. f"5O'QHGQK
*/ LN5LT'CE
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package com.tot.count; [v"Z2F<.=
import tot.db.DBUtils; I1E9E$m5\<
import java.sql.*; .Az36wD
/** LBK{-(%
* 2@zduL'do_
* @author g^]Iw~T6$
*/ /IUu-/ D
public class CountControl{ )Fv.eIBY
private static long lastExecuteTime=0;//上次更新时间 C:J;'[,S
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 fkzSX8a9}
/** Creates a new instance of CountThread */ 2H|:/y
public CountControl() {} ccuGM W G*
public synchronized void executeUpdate(){ .c"nDCFVR
Connection conn=null; QF"7.~~2
PreparedStatement ps=null; 9b+jT{Tg
try{ >q:%?mi
conn = DBUtils.getConnection(); b0$)G-E/Y
conn.setAutoCommit(false); @N>7+
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); yV{B,T`W
for(int i=0;i<CountCache.list.size();i++){ r<+C,h;aww
CountBean cb=(CountBean)CountCache.list.getFirst(); k5S;G"iJ
CountCache.list.removeFirst(); 2!/Kt
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ps.setInt(1, cb.getCountId()); [MTd<@
ps.executeUpdate();⑴ !LN8=u.
//ps.addBatch();⑵ jfxNV2[
} wX"hUu
//int [] counts = ps.executeBatch();⑶ i?6&4
conn.commit(); QQ3<)i
}catch(Exception e){ >j5\J_(;D
e.printStackTrace(); X1|
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} finally{
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try{ At(88(y-W
if(ps!=null) { )5Khl"6!z
ps.clearParameters(); EjR(AqZY
ps.close(); Uk?G1]$mL
ps=null; uYUFxm
} uks75W!}U
}catch(SQLException e){} h:%,>I%{
DBUtils.closeConnection(conn); @YI{ E*?S
} U6]#RxH
} Ia&*JYM[
public long getLast(){ n$/|r
return lastExecuteTime; bWswF<y-
} )/;KxaKt
public void run(){ Tru{8]uMH
long now = System.currentTimeMillis(); 7*5B
if ((now - lastExecuteTime) > executeSep) { \zO.#H
//System.out.print("lastExecuteTime:"+lastExecuteTime); r<`:Q]
//System.out.print(" now:"+now+"\n"); d9f7 &
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +K4XMf
lastExecuteTime=now; ]at$ohS
executeUpdate(); (g##wa)L
} .<hHK|HF
else{ O*xx63%jR
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @j46Ig4~b
} cI=6zMB
} >;fVuy
} OdzeHpH3g
//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 Cy~ IB [
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类写好了,下面是在JSP中如下调用。 s.2f'i+
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<% ?XBdBR_"^
CountBean cb=new CountBean(); eHphM;C
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); !7N:cx'Qy
CountCache.add(cb); F5o8@ Ib]:
out.print(CountCache.list.size()+"<br>"); =L!&Z
CountControl c=new CountControl(); U%q)T61
c.run(); KYFKH+d>m
out.print(CountCache.list.size()+"<br>"); 0@ `]m
%>