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: cp<jwcc!
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CountBean.java UqZ#mK i
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/* f/RDo4
* CountData.java 'K|tgsvgme
* iZDZ/hohv
* Created on 2007年1月1日, 下午4:44 V-TWC@Y"
* c9)5G+
* To change this template, choose Tools | Options and locate the template under lM-*{<B
* the Source Creation and Management node. Right-click the template and choose 2@#`x"0
* Open. You can then make changes to the template in the Source Editor. _=RK
*/ 1#
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package com.tot.count; Gmp`3
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/** w0 0Ba^W
* !`EhVV8u-_
* @author W05>\Rl
*/ MJ0UZxnl
public class CountBean { (YH/#n1"{
private String countType; (GI]Uyn
int countId;
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/** Creates a new instance of CountData */ g?d*cwtU
public CountBean() {} zCdzxb_h"
public void setCountType(String countTypes){ >gLLr1L\
this.countType=countTypes; N_),'2
} Ig M_l=
public void setCountId(int countIds){ Y]>Qu f.!
this.countId=countIds; O)Mf/P'
} "/}cV5=Z
public String getCountType(){ @O%d2bgEWV
return countType; ;IYH5sG{
} KK4"H]!.
public int getCountId(){ .WT^L2l%
return countId; f:|O);nM
} hXx.
} {r2fIj~V
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CountCache.java a#G]5TZ
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/* S|?Ht61k
* CountCache.java &b7i> ()
* %1jApCJ
* Created on 2007年1月1日, 下午5:01 *.ZU" 5e
* aR~Od Ys
* To change this template, choose Tools | Options and locate the template under I~.d/!>Z
* the Source Creation and Management node. Right-click the template and choose <OC|z3na_
* Open. You can then make changes to the template in the Source Editor. .&Ok53]b
*/ xRU ~hQ
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package com.tot.count; KGoHn6jM
import java.util.*; l`A4)8Y@
/** ,t=12R]>
* ,dO$R.h
* @author )mb RG9P
*/ Z2x%
public class CountCache { :u$+lq
public static LinkedList list=new LinkedList(); Qo;#}%}^^
/** Creates a new instance of CountCache */ )Mj
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public CountCache() {} ';0NWFP
public static void add(CountBean cb){ J\ V.J/
if(cb!=null){ 3Ta<7tEM
list.add(cb); Cq-#|+zr
} Ud8*yB
} ';hTGLq\X
} oz- k_9%
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CountControl.java tuiQk=[c
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/* 11Hf)]M
* CountThread.java tSvklI
* U.B=%S
* Created on 2007年1月1日, 下午4:57 t|Ipxk.)
* p!~{<s]
* To change this template, choose Tools | Options and locate the template under "=BO,see9
* the Source Creation and Management node. Right-click the template and choose 5h4E>LB.B
* Open. You can then make changes to the template in the Source Editor. %Fg}"=f1
*/ g}]EIv{
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package com.tot.count; U~w g'
import tot.db.DBUtils; MN22#G4j^w
import java.sql.*; ,LHQ@/}A C
/** mzX <!
* l6S6Y
* @author 2i@t;h2E
*/ !&Z,ev
public class CountControl{ ]$vJK
private static long lastExecuteTime=0;//上次更新时间 N3`W%ws`~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2%DleR'i
/** Creates a new instance of CountThread */ P6E=*^^m(
public CountControl() {} +L$,jZqS
public synchronized void executeUpdate(){ Kx;DmwX-
Connection conn=null; Twj?SV
PreparedStatement ps=null; M5Twulz/w
try{ (cj3[qq
conn = DBUtils.getConnection(); (3=(g
conn.setAutoCommit(false); iWN-X
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .u_k?.8|
for(int i=0;i<CountCache.list.size();i++){ XFg.Z+ #
CountBean cb=(CountBean)CountCache.list.getFirst(); 0kD8w j%
CountCache.list.removeFirst(); P"g
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ps.setInt(1, cb.getCountId()); CY4_=
ps.executeUpdate();⑴ |= frsf~?
//ps.addBatch();⑵ ;|hEXd?b
} B!(t<W8cu
//int [] counts = ps.executeBatch();⑶ ffQ%GV_
conn.commit(); PZdYkbj
}catch(Exception e){ epH48 )2
e.printStackTrace(); .2b) rKo~
} finally{ ^!*?vHx:
try{ Z-{!Z;T)z
if(ps!=null) { Bn"r;pqWiT
ps.clearParameters(); [wM<J$=2
ps.close(); F)0I7+lP
ps=null; a#0GmK
} /Jc?;@{
}catch(SQLException e){} |m%M$^sZ}
DBUtils.closeConnection(conn); &E{5k{Y
} 6rnehv!p
} @x@w<e%
public long getLast(){ PSdH9ea
return lastExecuteTime; r]{fjw(~
} lbES9o5
public void run(){ O^]I>A#d
long now = System.currentTimeMillis(); X'&$wQ6,K
if ((now - lastExecuteTime) > executeSep) { TgaDzF,j{A
//System.out.print("lastExecuteTime:"+lastExecuteTime); / -=(51}E
//System.out.print(" now:"+now+"\n"); jz[|rwAp
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _e.b#{=9
lastExecuteTime=now; (jD..qMs#
executeUpdate(); a .5s5g)8
} T2wn!N?r
else{ 8j,_
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f/b }X3K
}
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} ;UgRm#
} 6bg+U`&g
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 0NSn5Hq
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类写好了,下面是在JSP中如下调用。 |zu>G9m
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<% v.1= TBh
CountBean cb=new CountBean(); (oxe\Qk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 'D-#,X
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CountCache.add(cb); yvxC/Jo4
out.print(CountCache.list.size()+"<br>"); 6QRfju'
CountControl c=new CountControl(); =3=KoH/'
c.run(); r1FE$R~C=
out.print(CountCache.list.size()+"<br>"); F.=uJdl.!
%>