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: ":meys6t#
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CountBean.java W-8U~*/
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/* -
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* CountData.java Gdu5
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* )a=58r07
* Created on 2007年1月1日, 下午4:44 Ix59(g
* tSf$`4
* To change this template, choose Tools | Options and locate the template under :g~X"C1s
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. DKnlbl1^?
*/ _t7}ny[
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package com.tot.count; 9:v0gE+.
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/** N7l`-y
* 6M^NZ0~J
* @author _B6W:k|-7l
*/ iU1yJ=
public class CountBean { /9o
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private String countType; cqSo%a2
int countId; vvwQ/iJO4Q
/** Creates a new instance of CountData */ \\d!z-NOk?
public CountBean() {} >gSiH#>
public void setCountType(String countTypes){ A(84cmq!q
this.countType=countTypes; `ttqgv\
} l RM7s(^l
public void setCountId(int countIds){ tMDJ,rT
this.countId=countIds; 6!T9VL\=H
} 41XS/# M$*
public String getCountType(){ :oeDksld
return countType; ~C31=\$
} |1/UC"f
public int getCountId(){ 5oTj^W8M(
return countId; ;_dOYG1
} h( V:-D
} 3I.0jA#T&/
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CountCache.java 8ZN"-]*
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/* >X58 zlxk
* CountCache.java `iZ){JfAH
* 9h/JW_
* Created on 2007年1月1日, 下午5:01 30fqD1_{
* ?qJt4Om
* To change this template, choose Tools | Options and locate the template under LLD#)Jl{?
* the Source Creation and Management node. Right-click the template and choose 7)zF8V
* Open. You can then make changes to the template in the Source Editor. |EZ\+!8N:{
*/ 3bBCA9^se
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package com.tot.count; &peUC n
import java.util.*; /BQB7vL
/** A8T75?lL(
* MY w3+B+Jj
* @author uWjSqyb:
*/ +LhV4@zC
public class CountCache { /3KPK4!m
public static LinkedList list=new LinkedList(); |x+g5~$
/** Creates a new instance of CountCache */ jxdX7aik
public CountCache() {} $_Kcm"oj
public static void add(CountBean cb){ Yj{-|2YzL
if(cb!=null){ E'iN==p_:
list.add(cb); m/bP`-/,
} EN-;@P9;C
} lK"m|Z
} $VNj0i. Pr
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CountControl.java Q^ }Ib[
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/* Em]2K:
* CountThread.java 5D6 ,B
* 76eF6N+%}t
* Created on 2007年1月1日, 下午4:57 `3?5Z/,y
* M;j)F
* To change this template, choose Tools | Options and locate the template under WvN{f*
* the Source Creation and Management node. Right-click the template and choose A81'ca/
* Open. You can then make changes to the template in the Source Editor. {g7~e{2
*/ 59#o+qo4
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package com.tot.count; :x[SV^fw[
import tot.db.DBUtils; X0 ^~`g
import java.sql.*; EN/r{Cm$B
/** mhW*rH*m
* i TLX=.M
* @author ncdj/C
*/ #t<
public class CountControl{ S.R|Bwj}(Y
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 sL4j@Lt
/** Creates a new instance of CountThread */ xRbtiFk9H
public CountControl() {} yN{TcX
public synchronized void executeUpdate(){ Csf!I@}Z
Connection conn=null; _~.S~;o!b
PreparedStatement ps=null; vX}#wDNP
try{ <^(>o
conn = DBUtils.getConnection(); T8NDS7&?
conn.setAutoCommit(false); V {C{y5
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); g@|2z
for(int i=0;i<CountCache.list.size();i++){ xU;/LJ6
CountBean cb=(CountBean)CountCache.list.getFirst(); V:
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CountCache.list.removeFirst(); d=eIsP'h
ps.setInt(1, cb.getCountId()); :x3"Cj
ps.executeUpdate();⑴ F10TvJ
U
//ps.addBatch();⑵ [9d4 0>e
} =:*2t
//int [] counts = ps.executeBatch();⑶ _V,bvHWlM
conn.commit(); \\P*w$c
}catch(Exception e){ $!7$0WbC
e.printStackTrace(); C$4!|Wg3
} finally{ @MKf$O4K
try{ a)QSq<2*
if(ps!=null) { 8 -YC#&
ps.clearParameters(); ht_'GBS)
ps.close(); ZtGtJV"H
ps=null; srK9B0I
} x(7Q5Uk\
}catch(SQLException e){} td 5!
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DBUtils.closeConnection(conn); C;I:?4
} 61Wh %8-
} H(tT8Q5i
public long getLast(){ 1O2jvt7M
return lastExecuteTime; Sb.%B^O
} KnC:hus
public void run(){ F$@(0c
long now = System.currentTimeMillis(); Eg(.L,dj
if ((now - lastExecuteTime) > executeSep) { |+Cd2[hN
//System.out.print("lastExecuteTime:"+lastExecuteTime); )1gOO{T]h?
//System.out.print(" now:"+now+"\n"); Jd28/X5&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w5`EJp8MC
lastExecuteTime=now; \49s;\I]
executeUpdate(); "sYZ3
} Xbu P_U'
else{ ihd^P]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); UsgrI>|l
} s"~3.J
} |3G;Rh9w,
} vg8Yc
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 #z =$*\u
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类写好了,下面是在JSP中如下调用。 |ZG0E
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<% j8W<iy
CountBean cb=new CountBean(); 0M!GoqaA
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e.WKf,e"X
CountCache.add(cb); d}<-G.&_
out.print(CountCache.list.size()+"<br>"); `r]C%Y4?
CountControl c=new CountControl(); =Q #d0Q
c.run(); Ff1!+P,
out.print(CountCache.list.size()+"<br>"); 8'M:uI
%>