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: uG${`4
IT'~.!o7/
CountBean.java bJx{mq
NyeGa
/* %h4pIA
* CountData.java _^0yE_ili
* 5owUQg,W
* Created on 2007年1月1日, 下午4:44 Q/1
6D
* ,CA,7Mu:
* To change this template, choose Tools | Options and locate the template under 5A>W;Q\4
* the Source Creation and Management node. Right-click the template and choose oz(<e
* Open. You can then make changes to the template in the Source Editor. D ( <_1
*/ X%h1r`h&
[6FCbzS_W
package com.tot.count; =xS(Er`r
n^UrHHOL
/** iKv{)5
* >C*q
* @author 1WfN_JKB5
*/ ;B:'8$j$
public class CountBean { kC!7<%(
private String countType; B+`m
int countId; gX{V>T(<
/** Creates a new instance of CountData */ A%"mySW
public CountBean() {} 38>8{Ma
public void setCountType(String countTypes){ f]h99T
this.countType=countTypes; \XCs(lNh
} -9UQs.Nv
public void setCountId(int countIds){ .o]vjNrd/
this.countId=countIds; Y(m/E.h.~
} Y@Lv>p
public String getCountType(){ ZcYxH|Gn
return countType; i
jg'X#E
} ']Nw{}eS`
public int getCountId(){ so9h6K{qcp
return countId; E@}t1!E<
} S@k4k^Vg
} D`o*OlU
WID4 {>G2
CountCache.java >/. -N
JrQd7
/* u%Hegqn
* CountCache.java 6w0/;8(_m
* HH&`f3
* Created on 2007年1月1日, 下午5:01 G)?VC^Q
* </5uB'
B ^
* To change this template, choose Tools | Options and locate the template under isLIfE>
* the Source Creation and Management node. Right-click the template and choose 9F(<n
* Open. You can then make changes to the template in the Source Editor. 2ZNTj u7h
*/ <*i
'
^*C8BzcH
package com.tot.count; exiCy1[+
import java.util.*; ' &^:@V
/** Eyxw.,rB/
* K=;z&E=<c
* @author a-MDZT<xA+
*/ 5)wz `OS
public class CountCache { w6F4o;<PR
public static LinkedList list=new LinkedList(); q=M!YWz
/** Creates a new instance of CountCache */ S#/[>Cb
public CountCache() {} jQFAlO(E':
public static void add(CountBean cb){ *8CI'UX
if(cb!=null){ G +o)s
list.add(cb); m*6C *M
} + t({:>E
} k#_B^J&d
} f\nF2rlu
u}W R1u[
CountControl.java 9KN75<n
AMp[f%X
/* Q mT L-
* CountThread.java OxqK}%=Bw
* |2,u!{
* Created on 2007年1月1日, 下午4:57 4GH?$p|LX
* 8{Bcl5]<
* To change this template, choose Tools | Options and locate the template under Z!0D97^
* the Source Creation and Management node. Right-click the template and choose th}Q`vg0
* Open. You can then make changes to the template in the Source Editor. Y,RBTH
*/ I dgha9K
2j9Mr
package com.tot.count; '2vZ%C$
import tot.db.DBUtils; ypM0}pdvTp
import java.sql.*; x6d+`4
/** {9q~bt
* OGw =e{
* @author IP~*_R"bM
*/ h|$.`$
public class CountControl{ Kr3L~4>
private static long lastExecuteTime=0;//上次更新时间 9+)5 #!0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 aF7" 4^ P
/** Creates a new instance of CountThread */ 8
;y N
public CountControl() {} +Em+W#i%?
public synchronized void executeUpdate(){ vn}:$|r$J
Connection conn=null; p&/}0eL y
PreparedStatement ps=null; Zg"g/I.+d
try{ 7%)
F]
conn = DBUtils.getConnection(); ~4S@kYe{3K
conn.setAutoCommit(false); ^a#Vp
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R#.FfWTZ
for(int i=0;i<CountCache.list.size();i++){ p}$VBl$'
CountBean cb=(CountBean)CountCache.list.getFirst(); BUqe~E|I
CountCache.list.removeFirst(); ~mP#V
ps.setInt(1, cb.getCountId()); W-ErzX
ps.executeUpdate();⑴ 5(R ./
//ps.addBatch();⑵ 1K.i>]}>
} N2[EdOJT_
//int [] counts = ps.executeBatch();⑶ w#_/CUL
conn.commit(); PTfTT_t
}catch(Exception e){ ]|ew!N$ar=
e.printStackTrace(); .Xnw@\k'
} finally{ 8x#SpDI
try{ 6," 86
if(ps!=null) { :QT0[P5O
ps.clearParameters(); H,bYzWsrPo
ps.close(); } QVREj
ps=null; N=]2vyh
} #q'J`BC
}catch(SQLException e){} r8x<-u4
DBUtils.closeConnection(conn); x?v/|
} Z+!._uA
} %;$zR}
public long getLast(){ s4uZ;
return lastExecuteTime; s{\USD6
} >_bH,/D'
public void run(){ 3@P
2]Q~D
long now = System.currentTimeMillis(); qT7E"|.$
if ((now - lastExecuteTime) > executeSep) { <\l@`x96"D
//System.out.print("lastExecuteTime:"+lastExecuteTime); OPHf9T3H
//System.out.print(" now:"+now+"\n"); ^t,sehpR:l
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); GY@(%^
lastExecuteTime=now; !8S$tk
executeUpdate(); I/:M~ b
} N) D;)ZH
else{ n\Y{?x
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); r!A1Sfo4P
} P/uk]5H^
} `IL''eJug_
} \@8j&],dl
//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 Rg@W0Bc)
Y|$3%t
类写好了,下面是在JSP中如下调用。 WfYu-TK*
*F7ksLH|q
<% AG/?LPJ
CountBean cb=new CountBean(); l>p S23
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |t](4
CountCache.add(cb); /sVy"48-
out.print(CountCache.list.size()+"<br>"); !jZXh1g%
CountControl c=new CountControl(); B=?4; l7
c.run(); E{+V_.tlu
out.print(CountCache.list.size()+"<br>"); 80=6B
%>