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: ,c@r`
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CountBean.java j \!~9
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/* 03~+-h&n
* CountData.java 7X(rLd
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* :-$cdZ3E
* Created on 2007年1月1日, 下午4:44 /z/hUa
* *Hxj_
* To change this template, choose Tools | Options and locate the template under \nC5 ,Rz
* the Source Creation and Management node. Right-click the template and choose uFGv%W
* Open. You can then make changes to the template in the Source Editor. W"W@WG9X0
*/ g4zT(,ZY
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package com.tot.count; A,3@j@bdy
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/** 5tN%a>D%
* Bh\
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* @author g!p+rq_f
*/ sVE>=0TVP
public class CountBean { Z~duJsH
private String countType; %|#P&`
int countId; P=f<#l"v
/** Creates a new instance of CountData */ F"-S~I7'L
public CountBean() {}
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public void setCountType(String countTypes){ p^p'/$<6_
this.countType=countTypes; 2dv|6p
} U#8\#jo
public void setCountId(int countIds){ D9}d]9]$
this.countId=countIds; "B3iX@C
} eA~J4k_
public String getCountType(){ )EhTM-1
return countType; "g
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} @:S$|D~
public int getCountId(){ yfPCGCOW?
return countId; H%*~l
} ^ze@#Cp
} j'G"ZPw1
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CountCache.java (jp1; #P!
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/* R g%R/p)C
* CountCache.java hp?ad
* &i4
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* Created on 2007年1月1日, 下午5:01
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* =@bXGMsV!
* To change this template, choose Tools | Options and locate the template under Q{%HW4lg
* the Source Creation and Management node. Right-click the template and choose Q.j-C}a
* Open. You can then make changes to the template in the Source Editor. 3m-edpH
*/ uU8*$+ "
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package com.tot.count; h-z%C6
import java.util.*; +}Qv6s#
/** E`oSi
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* ZkJY.H-F
* @author &>d:ewM\
*/ $=\oJ-(!@S
public class CountCache { @qg0u#k5
public static LinkedList list=new LinkedList(); ~0VwF
/** Creates a new instance of CountCache */ I>N-95
public CountCache() {} *D,v>(
public static void add(CountBean cb){ ~@b9
if(cb!=null){ ==jkp
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list.add(cb); "U/NMGMj
} qg_>`Bv"a
} rg#qSrHp
} 8r7/IGFg
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CountControl.java Y}V)4j
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/* @oe3i
* CountThread.java Hl%+F0^?
* >i><s>=I`
* Created on 2007年1月1日, 下午4:57
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* TzD:bKE&
* To change this template, choose Tools | Options and locate the template under ~G|{qVO7A
* the Source Creation and Management node. Right-click the template and choose {GGO')p
* Open. You can then make changes to the template in the Source Editor. :ofE8]
*/ :Olj
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package com.tot.count; -9tXv+v?
import tot.db.DBUtils; )_x8?:lv
import java.sql.*; 4fU5RB7%
/** a=}">=]7
* t<KEx^gb
* @author a$+e8>
*/ a9mr-`<
public class CountControl{ 8KtF<`A)
private static long lastExecuteTime=0;//上次更新时间 I&Eg-96@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 N#2nH1C
/** Creates a new instance of CountThread */ PBPJ/puW
public CountControl() {} #b]}cwd!
public synchronized void executeUpdate(){ ;6\Ski0=l
Connection conn=null; e>)}_b
PreparedStatement ps=null; :5q*46n
try{ @; j0c_^"!
conn = DBUtils.getConnection(); zm_hLk
conn.setAutoCommit(false); g,z&{pZch
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); gZ79u
for(int i=0;i<CountCache.list.size();i++){ ~gzpX,{n
CountBean cb=(CountBean)CountCache.list.getFirst(); hj#+8=
CountCache.list.removeFirst(); H)?" 8 s
ps.setInt(1, cb.getCountId()); ]0/~6f
ps.executeUpdate();⑴ +Qb2LR
//ps.addBatch();⑵ ]UpHD.Of[t
} 4n.i<K8K[
//int [] counts = ps.executeBatch();⑶ lHj7O&+
conn.commit(); 9X^-)G>
}catch(Exception e){ J^<j=a|D
e.printStackTrace(); |)>GeE
} finally{ b`;b}ug
try{ Eb{4.17b
if(ps!=null) { Qbe{/
ps.clearParameters();
onS{
ps.close(); TF([yZO'
ps=null; (cqA^.Td
} 'amex
}catch(SQLException e){} `[W)6OUCx}
DBUtils.closeConnection(conn); 8xGkh?%
} \-`oFe"
} 4HYH\ey
public long getLast(){ }O-%kl
return lastExecuteTime; iM-hWhU
} [wpt[zG
public void run(){ (*^E7
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long now = System.currentTimeMillis(); c9_4ohB
if ((now - lastExecuteTime) > executeSep) { d+$[EDix
//System.out.print("lastExecuteTime:"+lastExecuteTime); *b 7
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//System.out.print(" now:"+now+"\n"); })=c:h&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s-YV_
lastExecuteTime=now; _o=`-iy9
executeUpdate(); \2LA%ZU
} n6-!@RYr
else{ fPuQ,J2=
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); oqm{<g?2
} FL_ arhrqD
} \Jj'60L^
} bKTwG@{/k
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 )8A=yrTIT
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类写好了,下面是在JSP中如下调用。 V1+o3g{}
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<% eVbh$cIrZ
CountBean cb=new CountBean(); :-jP8X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mm9S#Ya
CountCache.add(cb); cB{;Nh6"
out.print(CountCache.list.size()+"<br>"); o@V/37!
CountControl c=new CountControl(); B2+_F"<;
c.run(); q~A|R
out.print(CountCache.list.size()+"<br>"); uS+b* :
%>