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: /al(=zf
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CountBean.java /3L1Un*
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/* JC_Y#kN@z
* CountData.java tTLD6#
* ;Bat!K7W
* Created on 2007年1月1日, 下午4:44 a:XVu0`(
* tUDOL-Tv
* To change this template, choose Tools | Options and locate the template under Og Y4J|<
* the Source Creation and Management node. Right-click the template and choose m3+MRy5
* Open. You can then make changes to the template in the Source Editor. fOdkzD,
*/ $[by)
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package com.tot.count; 0;#%KC,
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/** kBS;SDl)
* C;1A$]bk
* @author e>#*$4tg
*/ mawomna
public class CountBean { 2+s_*zM-
private String countType; )~rfx
int countId; |ITp$_S
/** Creates a new instance of CountData */ 4askQV &hj
public CountBean() {} "
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public void setCountType(String countTypes){ <IC=x(T
this.countType=countTypes; 26G2. /**<
} SsIy ;l
public void setCountId(int countIds){ <%8j#@OdZ
this.countId=countIds; cuO(*%Is1
} 9gZMfP
public String getCountType(){ C},;M@xV
return countType; w-C~
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} TUw^KSa
public int getCountId(){ 1`^l8V(
return countId; aEo!yea
} o8-BTq8
} ] QGYEjW
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CountCache.java j&6,%s-M`a
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/* '_lyoVP
* CountCache.java zH0%;
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* puF'w:I(
* Created on 2007年1月1日, 下午5:01 9z$]hl
* : ^F+mQN
* To change this template, choose Tools | Options and locate the template under X,C&nqVFm8
* the Source Creation and Management node. Right-click the template and choose 5|my}.TR
* Open. You can then make changes to the template in the Source Editor. J;W(}"cFq
*/ ?l!L
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package com.tot.count; %0fF_OU
import java.util.*; `KqMcAW
/** Dd-;;Y1C
* Sf);j0G,D
* @author w17\ \[
*/ peCmb)>Sa
public class CountCache { <H<5E'm
public static LinkedList list=new LinkedList(); kT&-:: ^R
/** Creates a new instance of CountCache */ ,24NMv7
public CountCache() {} zlF*F8>m
public static void add(CountBean cb){ L$=@j_V2
if(cb!=null){ 1+~JGY#
list.add(cb); L-hK(W!8pt
} x|d Xa0=N_
} !C
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} es]\xw
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CountControl.java RrSSAoz1
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/* XKp.]c wP
* CountThread.java "u~l+aW0
* %jdV8D#Q
* Created on 2007年1月1日, 下午4:57 $#2ik~]>
* )IPnSh/<
* To change this template, choose Tools | Options and locate the template under QWH1xId
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. '(mJ*Eb
*/ pisk v[
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package com.tot.count; S(9Xbw)T
import tot.db.DBUtils; [HI&>dm=$
import java.sql.*; ]wh8m1
/** LTj;e[
* fu?5gzT+b
* @author U_v{Vs
*/ /+l3
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public class CountControl{ `au('
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private static long lastExecuteTime=0;//上次更新时间 z`qBs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 hLPg=8nJ_
/** Creates a new instance of CountThread */ D
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public CountControl() {} 5 WSu
public synchronized void executeUpdate(){ /ZqBO*]
Connection conn=null; zWoPa,
PreparedStatement ps=null; 3v)v92;
try{ +(0Fab8g
conn = DBUtils.getConnection(); #DApdD9M
conn.setAutoCommit(false); #P.jlpZk
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); py`RH)
for(int i=0;i<CountCache.list.size();i++){ Ja>UcE29
CountBean cb=(CountBean)CountCache.list.getFirst(); cN0|! nm*
CountCache.list.removeFirst(); W.iL!x.B@
ps.setInt(1, cb.getCountId()); R#i|n<x
ps.executeUpdate();⑴ j!q5 Bc?
//ps.addBatch();⑵ ZHUAM59bx
} `,i'vb`W#b
//int [] counts = ps.executeBatch();⑶ fZL%H0&
conn.commit(); zvf:*Na")
}catch(Exception e){ ;F9<Yv
e.printStackTrace(); oEbgyT gB
} finally{ |Ak>kQJ(1z
try{ P1;T-.X~&
if(ps!=null) { g9|B-1[
ps.clearParameters(); L@2%a'
ps.close(); MzT#1~
ps=null; \?c0XD
} ^8$CpAK]M
}catch(SQLException e){} ]y3V^W#
DBUtils.closeConnection(conn); Ni*f1[sI<
} o"~ODN"L
} Y$b4Ga9j
public long getLast(){ Zs<}{`-
return lastExecuteTime; 9PjL
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} `<kHNcm
public void run(){ <8Ek-aNNt
long now = System.currentTimeMillis(); ,oX48Wg_+
if ((now - lastExecuteTime) > executeSep) { 4b=hFwr[?
//System.out.print("lastExecuteTime:"+lastExecuteTime); CZRrb 84
//System.out.print(" now:"+now+"\n"); x7K
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); cE>K:3n
lastExecuteTime=now; {[G2{ijRz
executeUpdate(); ]vJZ v"ACn
} (__=*ew
else{ K]' 84!l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); bhe~ekb
} wLC!vX.S
} 4v9zFJ<Z
} TU$PAwn=
//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 [tsi8r=T
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类写好了,下面是在JSP中如下调用。 tW 53&q\=
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<% 6eE%x?#
CountBean cb=new CountBean(); g\)+
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "}Kvx{L8
CountCache.add(cb); 2K<rK(
out.print(CountCache.list.size()+"<br>"); i)f3\?,,
CountControl c=new CountControl(); Cj%SW <v|
c.run(); #P *%FgROl
out.print(CountCache.list.size()+"<br>"); W/ZmG]sZE
%>