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;~$J
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CountBean.java wf1p/bpf
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/* 7&OJ8B/
* CountData.java {IvA 5^
* NQ;$V:s)
* Created on 2007年1月1日, 下午4:44 )''V}Zn.X
* EaHJl
* To change this template, choose Tools | Options and locate the template under KZ%us 6
* the Source Creation and Management node. Right-click the template and choose (;^>G[
* Open. You can then make changes to the template in the Source Editor. GQJ4d-w
*/ aJtpaW@
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package com.tot.count; Ziub%C[oV
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/** C@Go]*c
* ,FH1yJ;Y&
* @author u??ti
OK{
*/ #d*gWwnx"
public class CountBean { vceD/ N8
private String countType; u<N`;s
int countId; q,%Fvcmx+e
/** Creates a new instance of CountData */ &l!T2PX!
public CountBean() {} olA+B
public void setCountType(String countTypes){ $~/cxLcT
this.countType=countTypes; r\FZ-gk}Q
} Iz-mUD0;
public void setCountId(int countIds){ #qR 6TM&;
this.countId=countIds; =J]EVD
} 'RF`XX
public String getCountType(){ @V:Y%#%
return countType; rnQ_0d
} X9SOcg3a
public int getCountId(){ ;ND[+i2MN
return countId; ^OX}y~'
} p >ua{}!L
} -*~
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CountCache.java sf[|8}(
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/* pwS"BTZ
* CountCache.java GCiG50Z=
* u*W! !(P/
* Created on 2007年1月1日, 下午5:01 zJl;|E".
* *]h"J]
* To change this template, choose Tools | Options and locate the template under 2<p@G#(
* the Source Creation and Management node. Right-click the template and choose k9<UDg_ Y
* Open. You can then make changes to the template in the Source Editor. E
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*/ ^);M}~
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package com.tot.count; u0,QsD)_X0
import java.util.*; )ZBNw{nh
/** n-],!pL^
* ?daxb
* @author 2kDv
(".
*/ -K(d]-yv
public class CountCache { Zlh 2qq
public static LinkedList list=new LinkedList(); D)DD 6
/** Creates a new instance of CountCache */ S@S4<R1{\
public CountCache() {} ys>n%24qP
public static void add(CountBean cb){ 'UxI-Lt
if(cb!=null){ /Z!$bD
list.add(cb); @9n|5.i
} w0Ex}
} 0'.z|Jg=
} XzX2V">(%
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CountControl.java +>;Ux1'@
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/* !L
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* CountThread.java "\`Fu
* c}|.U
* Created on 2007年1月1日, 下午4:57 DTM(SN8R+n
* Lk@+iHf
* To change this template, choose Tools | Options and locate the template under a#% *H
* the Source Creation and Management node. Right-click the template and choose ts@Z5Yw*!
* Open. You can then make changes to the template in the Source Editor. &!O?h/&X3
*/ ZWGX*F#}P
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package com.tot.count; k\;D;e{
import tot.db.DBUtils; wbcip8<t
import java.sql.*; n'{jc6&|
/** Mp!1xx
* aXQAm$/
>
* @author Q&w_kz.
*/ &~/g[\Y
public class CountControl{ He5y;5
private static long lastExecuteTime=0;//上次更新时间 LklE,W
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 UR=s=G|
/** Creates a new instance of CountThread */ W2h4ej\s
public CountControl() {} Vn:v{-i
public synchronized void executeUpdate(){ 7][fciZN
Connection conn=null; #I.~+M
PreparedStatement ps=null; }vx,i99W?
try{ $joGda
conn = DBUtils.getConnection(); fp\mBei
conn.setAutoCommit(false); YQFz6#Ew
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R@5eHP^
for(int i=0;i<CountCache.list.size();i++){ O-)[!8r
CountBean cb=(CountBean)CountCache.list.getFirst(); wb(S7OsMO
CountCache.list.removeFirst(); s_RK x)w@
ps.setInt(1, cb.getCountId()); dhxzW@'nIL
ps.executeUpdate();⑴ }fkdv6mz
//ps.addBatch();⑵ ,Nhv#U<$
} E3[9!L8gb
//int [] counts = ps.executeBatch();⑶ &\~*%:C
conn.commit(); ?u:mscb
}catch(Exception e){ HWB\}jcA6u
e.printStackTrace(); )4s7,R
} finally{ !v=/f_6
try{ @&&}J
if(ps!=null) { !\d~9H%`B
ps.clearParameters(); ^>!&]@
ps.close(); @M-Q|
ps=null; K0C"s'q
} k}E_1_S(
}catch(SQLException e){} 0F![<5X
DBUtils.closeConnection(conn); qNHI$r'
} LEtGrA/%@b
} ~,KrL(jC
public long getLast(){ %3TioM[B
return lastExecuteTime; .>[l@x"
} Cg~1<J?2
public void run(){ oq,nfUA
long now = System.currentTimeMillis(); ni2 [K`
if ((now - lastExecuteTime) > executeSep) { I0Allw[
//System.out.print("lastExecuteTime:"+lastExecuteTime); fJ5mKN
//System.out.print(" now:"+now+"\n"); .57Fh)Y
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "q= ss:(
lastExecuteTime=now; >@cBDS<6R
executeUpdate(); 8%YyxoCH
} M=ag\1S&ZF
else{ fK]%*i_"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CMbID1M3
} |.yS~XFJS
} _[(EsIqc(F
} G4'Ee5(o
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 lfCr`[!E
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类写好了,下面是在JSP中如下调用。 'm|T"Ym~
bo<.pK$
<% IgwHC0W
CountBean cb=new CountBean(); &nVekE:!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); D4y!l~_,%M
CountCache.add(cb); Bfo#N31F}
out.print(CountCache.list.size()+"<br>"); Whp`\E<<
CountControl c=new CountControl(); jck(cc=R
c.run(); {g`!2"
out.print(CountCache.list.size()+"<br>"); -~xQ@ +./
%>