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: {w,^Z[<
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CountBean.java _TJkYz$
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/* VgY6M_V
* CountData.java q)@;8Z=_c
* c/F!cW{z^
* Created on 2007年1月1日, 下午4:44 <Nloh+n=
* vy7?]}MvV
* To change this template, choose Tools | Options and locate the template under wsR\qq
* the Source Creation and Management node. Right-click the template and choose {65YTt%
* Open. You can then make changes to the template in the Source Editor. G7GKO
*/ KB^GC5L>
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package com.tot.count;
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/** %Zfh6Bl\X
* U3M;{_g
* @author 5ff5M=M
*/ 1} _<q k9
public class CountBean { jCx*{TO
private String countType; 1xsJz^%V
int countId; ;<cCT!A
/** Creates a new instance of CountData */ fI.X5c>WK
public CountBean() {} a>y e
public void setCountType(String countTypes){ 6%o@!|=I
this.countType=countTypes; uzp\<\d-t
} g<w1d{Td
public void setCountId(int countIds){ d;3f80Kd*
this.countId=countIds; bx7hQzoX=b
} 5yW}#W>
public String getCountType(){ "79b>
return countType; >r4BI}8SK<
} u2':~h?l
public int getCountId(){ ?<OyJ|;V
return countId; rc`I l{~k
} !0Ak)Q]e'
} a_D K"8I
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CountCache.java ZXbq5p_
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/* q}E'x/s2m
* CountCache.java h9nh9a(2
* IG%x(\V-e
* Created on 2007年1月1日, 下午5:01 O!F"w!5@
* FELW?Q?k
* To change this template, choose Tools | Options and locate the template under ,&@FToR
* the Source Creation and Management node. Right-click the template and choose SM<qb0
* Open. You can then make changes to the template in the Source Editor. a94nB
*/ ep
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package com.tot.count; 2@&"*1(Xu
import java.util.*; 0'zjPE#
/** ~PN[ #e]
* idS+&:'
* @author )Dcee@/7S
*/ 5mZ9rLn
public class CountCache { CWD
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public static LinkedList list=new LinkedList(); sI4
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/** Creates a new instance of CountCache */ )%:
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public CountCache() {} 20Rm|CNH?
public static void add(CountBean cb){ ZS&lXgo
if(cb!=null){ nXh<+7
list.add(cb); f\:I1y
} B\dhw@hM
} L'"od;(6R
} 1@+&6UC
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CountControl.java (tg+C\
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/* 4LJOT_
* CountThread.java a=[|"J<M
* 1u*
(=!
* Created on 2007年1月1日, 下午4:57 S!
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* On@p5YRwW
* To change this template, choose Tools | Options and locate the template under ^<aj~0v
* the Source Creation and Management node. Right-click the template and choose a
uve&y"R
* Open. You can then make changes to the template in the Source Editor. G<~P||Lu^
*/ I%0J=V;o{
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package com.tot.count; Y~OyoNu2
import tot.db.DBUtils; L[:M[,?=`
import java.sql.*; .4=A:9
/** d%1Vby
* NVDvd6
* @author oTpoh]|[
*/ woU3WS0
public class CountControl{ r6+IJxUd
private static long lastExecuteTime=0;//上次更新时间 8PGuZw<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;s-fYS6(>{
/** Creates a new instance of CountThread */ !Ome;gS)
public CountControl() {} \JF 2'm\M
public synchronized void executeUpdate(){ ><)fK5x
Connection conn=null; r+MqjdXG
PreparedStatement ps=null; tqU8>d0^
try{ 49B6|!&I
conn = DBUtils.getConnection(); p"n3JV.~k+
conn.setAutoCommit(false); m&Y?]nbq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); c+<gc:#jy
for(int i=0;i<CountCache.list.size();i++){ _b[Pk;8}j;
CountBean cb=(CountBean)CountCache.list.getFirst(); \@7 4I7
CountCache.list.removeFirst();
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ps.setInt(1, cb.getCountId()); ?zK>[L
ps.executeUpdate();⑴ )Mw 3ZE92
//ps.addBatch();⑵ 7$:Jea
} mZ#IP
//int [] counts = ps.executeBatch();⑶ NV3oJ0f&2
conn.commit(); #@L<<Q8}
}catch(Exception e){ uq]E^#^
e.printStackTrace(); \&s$?r
} finally{ GS!1K(7
try{ mgBxcmv
if(ps!=null) { 0MOn>76$N
ps.clearParameters(); 9sB LCZ
ps.close(); vLcOZ^iK
ps=null; `6G:<wX
} u$1^=
}catch(SQLException e){} .wuRT>4G)G
DBUtils.closeConnection(conn); 7"k\i=
} yL3F
} oeG?2!Zh
public long getLast(){ CSE!Abg
return lastExecuteTime; w"h'rw
} m^a0JR}u9
public void run(){ EJTa~
long now = System.currentTimeMillis(); S%w67sGl4n
if ((now - lastExecuteTime) > executeSep) { h56s ~(?O
//System.out.print("lastExecuteTime:"+lastExecuteTime); G*^4CJ
//System.out.print(" now:"+now+"\n"); ^}hSsE
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x1QL!MB
lastExecuteTime=now; Ua>.k|>0
executeUpdate(); ?D=%k8)Y
} d%ncI0f`
else{ n,|YJ,v[
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); /_/Z/D!
} Hd~fSXFl
} ' ]vMOGG
} d|$-l:(J
//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 +PHuQ
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类写好了,下面是在JSP中如下调用。 8X=2# &)
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<% 9h^TOZK)
CountBean cb=new CountBean(); C3 (PI,,
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); BlfW~l'mx
CountCache.add(cb); sQa9M
out.print(CountCache.list.size()+"<br>"); )Z@hk]@?_[
CountControl c=new CountControl(); Th 5}?j7
c.run(); Oat
#%
out.print(CountCache.list.size()+"<br>"); D?9EO=
%>