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: >&KH!:OX|
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CountBean.java zMFTkDY
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/* n@RmH>"
* CountData.java /*T^7Y&
* "TZY)\{L
* Created on 2007年1月1日, 下午4:44 "!V`_ S;
* ]s AuL!
* To change this template, choose Tools | Options and locate the template under c
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* the Source Creation and Management node. Right-click the template and choose jez0 A
* Open. You can then make changes to the template in the Source Editor. gVfFEF.
*/ ,3Q~X$f
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package com.tot.count; 6dR+qJa6i
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/** k`8O/J
* t4_yp_
* @author ?J2A1iuq3
*/ <&l$xn
public class CountBean { MmN{f~Kq9
private String countType; #0aBQ+_8H
int countId; eTvWkpK+
/** Creates a new instance of CountData */ ['=O>YY
public CountBean() {} "Zgwe,#
public void setCountType(String countTypes){ EGUlLqP6e
this.countType=countTypes; hbH~Ya=+S
} *v+l,z4n
public void setCountId(int countIds){ oxlor,lw/
this.countId=countIds; ]yf?i350
} kk-<+R2
public String getCountType(){ RTcxZ/\"#
return countType; dDpAS#'s\
} wWb>V&3
public int getCountId(){ a+cMXMf
return countId; a31e.36g
} |VWT4*K
} 7sxX?u
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CountCache.java hi1Ial\Y
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/* s Z[[ymu8
* CountCache.java 0vm> *M*p
* hLLSmW(
* Created on 2007年1月1日, 下午5:01 O D}RnKL
* ~~OFymQ%?q
* To change this template, choose Tools | Options and locate the template under **hQb$
* the Source Creation and Management node. Right-click the template and choose uGMzU&+
* Open. You can then make changes to the template in the Source Editor. *#XZ*Ga
*/ '6dVe2V
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package com.tot.count; `s
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import java.util.*; >o?v[:u*
/** "#r)NYq`"|
* u;_h%z5K
* @author S\).0goOW
*/ 1y'Y+1.<
public class CountCache { e
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public static LinkedList list=new LinkedList(); \sAaVdZJH(
/** Creates a new instance of CountCache */ 'ztOl`I5V
public CountCache() {} {=ox1+d
public static void add(CountBean cb){ W7qh1}_%
if(cb!=null){ oZvG Kf
list.add(cb); 4`5yrCd
} )R JEOl1
} q*&R&K;q
} ~(^P(
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CountControl.java H{*Dc_
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/* +lx&$mr?
* CountThread.java 2|je{
* A`Z/B[)
* Created on 2007年1月1日, 下午4:57 M/?,Qii
* c
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* To change this template, choose Tools | Options and locate the template under l*1|B3#m!
* the Source Creation and Management node. Right-click the template and choose @L3XBV2
* Open. You can then make changes to the template in the Source Editor. |"gL{De
*/ p\w<~pN[
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package com.tot.count; H$h#n~W~
import tot.db.DBUtils; j<p.#jkT
import java.sql.*; I%3[aBz4
/** U N9hZ>9
* 7)lEZJK&T
* @author m-Eh0Zl>Z
*/ [s(D==8
public class CountControl{ K;RH,o1
private static long lastExecuteTime=0;//上次更新时间 l[/`kK
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _ox+5?>
/** Creates a new instance of CountThread */ b7QE
public CountControl() {} Za:j;u
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public synchronized void executeUpdate(){ gg/`{
Connection conn=null; ?_NKyiu95
PreparedStatement ps=null; "h sT^sy
try{ F` U~(>u'
conn = DBUtils.getConnection(); `6U!\D
conn.setAutoCommit(false); ` =>}*GS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); M13HD/~O
for(int i=0;i<CountCache.list.size();i++){ VzP az\e
CountBean cb=(CountBean)CountCache.list.getFirst(); 3kn-tM
CountCache.list.removeFirst(); G4)~p!TSQ
ps.setInt(1, cb.getCountId()); MR#*/Iw~
ps.executeUpdate();⑴ &W2*'$j"_
//ps.addBatch();⑵ ;]dD\4_hK
} 'C[tPP
//int [] counts = ps.executeBatch();⑶ 4ijtx)SA
conn.commit(); N''QQBUD
}catch(Exception e){ yKc-:IBb{u
e.printStackTrace(); u R0UfKK
} finally{ b[74$W{
try{ T`&zQQ6F'
if(ps!=null) { rW{!8FhI
ps.clearParameters(); C~ 1]
ps.close(); 1R2IlUlzFr
ps=null; &9yZfp
} \2\{c1df
}catch(SQLException e){} >+2&7u
DBUtils.closeConnection(conn); 9kL,69d2
} >P/36'
} k#].nQG
public long getLast(){ QZzamT)"
return lastExecuteTime; _ \D%
} w*qj0:i5as
public void run(){ =XP[3~
long now = System.currentTimeMillis(); kBo:)Vej4
if ((now - lastExecuteTime) > executeSep) { '2(m%X\6
//System.out.print("lastExecuteTime:"+lastExecuteTime); HlGSt$woX
//System.out.print(" now:"+now+"\n"); +,76|oMsQ%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `b?uQ\#-M
lastExecuteTime=now; 4b;Mb
executeUpdate(); =oBpS=<7
} KdVKvs[
else{ l=~!'1@L}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); YF5}~M ymF
} M>AxVL
} 7L!JP:v
} 9d5$cV
//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 T c WCr
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类写好了,下面是在JSP中如下调用。 -%asHDQ{
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<% }3(!kW
CountBean cb=new CountBean(); )Qbd/zd\U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XqTguO'
CountCache.add(cb); G/_IY;
out.print(CountCache.list.size()+"<br>"); z(|^fi(
CountControl c=new CountControl(); 5ya9VZ5#
c.run(); fkV@3sj
out.print(CountCache.list.size()+"<br>"); gaF6j!p
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