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: bH3-#mw5w
:~zK0v"
CountBean.java , YTuZS
#kA/,qyM
/* T1M4@j
* CountData.java *;Hvx32I
* 7$Bq.Lc#z
* Created on 2007年1月1日, 下午4:44 ="d}:Jl
* mJ#u] tiL
* To change this template, choose Tools | Options and locate the template under 4FGcCE3
* the Source Creation and Management node. Right-click the template and choose %$`pD
I )
* Open. You can then make changes to the template in the Source Editor. r<UZ\d -
*/ Xv]O1 f cI
fk#SD "iJ
package com.tot.count; 2o6KVQ
TN.mNl%
/** 1q}iUnR
* fg*IHha
* @author p r(:99~3
*/ tL 3]9qfj
public class CountBean { 9{'GrL
private String countType; Jq<&`6hn
int countId; 8"N<g'Yl,
/** Creates a new instance of CountData */ F.c,F R2
public CountBean() {} #J)sz,)(
public void setCountType(String countTypes){ [,8@oM#
this.countType=countTypes; >y(;k|-$
} nP0|nPWz#
public void setCountId(int countIds){ O<Ht-TN&
this.countId=countIds; ou6yi;
l%
} A%k@75V@
public String getCountType(){ l<(MC R*
return countType;
3RXq/E
} 8}XtVF;
public int getCountId(){ x: `oqbd
return countId; ucL}fnY1
} ['tGc{4
} 7xMvf<1P
BC Jo/m
CountCache.java QuT8(s1Q!
kHo0I8
/* (Z,v)TOXjV
* CountCache.java t*NZ@)>
* =v:vc~G6
* Created on 2007年1月1日, 下午5:01 J)x-Yhe
* g"`BNI]Qp
* To change this template, choose Tools | Options and locate the template under $!G7u<`na
* the Source Creation and Management node. Right-click the template and choose #:3ca] k
* Open. You can then make changes to the template in the Source Editor. .Quu_S_vH
*/ i,8h
B(M!
;8'hvc3i$
package com.tot.count; =;l.<{<VH
import java.util.*; A Ns.`S
/** #OqQD6
* \5_+6
* @author 3 i Id>
*/ (]w_}E]N
public class CountCache { Oq7M1|{
public static LinkedList list=new LinkedList(); "4<RMYQ
/** Creates a new instance of CountCache */ x{*g^f
public CountCache() {} d/v{I
public static void add(CountBean cb){ SGXXv
if(cb!=null){ Mi%i_T^i
list.add(cb); r?nvJHP
} T4]/w|?G
} P6u9Ngay
} hxP%m4xF +
WldlN?[j
CountControl.java }rj.N98
B:\\aOEj
/* zq>pK_WG
* CountThread.java )D{L<.i_
* b^~ keQ
* Created on 2007年1月1日, 下午4:57 "_eHK#)
* E/v.+m
* To change this template, choose Tools | Options and locate the template under $]2srRA^A
* the Source Creation and Management node. Right-click the template and choose Q>8F&p?R
* Open. You can then make changes to the template in the Source Editor. "9'~6b
*/ Oh3AbpTT
@%d g0F}h
package com.tot.count; 'Ybd'|t{}
import tot.db.DBUtils; |L}zB,
import java.sql.*; $sTbFY
/**
0w>V![
* `O?Kftv*
* @author VUpa^R
*/ eee77.@y-p
public class CountControl{ )h]~<
fU
private static long lastExecuteTime=0;//上次更新时间 E
(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :hJHjh
/** Creates a new instance of CountThread */ Jr$,w7tQn@
public CountControl() {} sD H^l)4h
public synchronized void executeUpdate(){ ROlef;/A
Connection conn=null; s6bILz-u
PreparedStatement ps=null; b`){f\#t
try{ K1>X%f^
conn = DBUtils.getConnection(); 5\gL+qM0
conn.setAutoCommit(false); D99g}
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `%IzW2v6
for(int i=0;i<CountCache.list.size();i++){ -^LUa]"E
CountBean cb=(CountBean)CountCache.list.getFirst(); ?oana%
CountCache.list.removeFirst(); xP#vAR
ps.setInt(1, cb.getCountId()); m5m}RWZ#
ps.executeUpdate();⑴ B>Tfyo
//ps.addBatch();⑵ :)o 4fOJ8
} O=~8+sa
//int [] counts = ps.executeBatch();⑶ ZKy)F-yX
conn.commit(); 7#d>a=$h
}catch(Exception e){ cyrVz4_a
e.printStackTrace(); d` %8qLIW
} finally{ ^0)Mc"&{
try{ BmR++ ?L
if(ps!=null) { Oxo?\
:T
ps.clearParameters(); fFDI qX
ps.close(); C))5,aX
ps=null; O<7Q>m
} t"x
8]Gy
}catch(SQLException e){} p4mi\~Q
DBUtils.closeConnection(conn); M8dv
y!D
} <Hd8Jd4f
} vUm#^/#I
public long getLast(){ 'D`O4TsP>
return lastExecuteTime; 'NJGez'b,
} j5Kw0Wy7
public void run(){ '!eg9}<
long now = System.currentTimeMillis(); !"1}zeve
if ((now - lastExecuteTime) > executeSep) { B7PkCS&X
//System.out.print("lastExecuteTime:"+lastExecuteTime); \|e>(h!l;
//System.out.print(" now:"+now+"\n"); `_%UK=m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $J6 Pv
lastExecuteTime=now; t/55tL
executeUpdate(); !%MI9Ok
} =og>& K
else{ KaVNRS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); DJ_[{WAV
} 9
5bi
W
} b-?wJSf|
} F.{{gpI
//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 $HgBzZ7A2
x}\x3U
类写好了,下面是在JSP中如下调用。 I(^pIe-
{1?94rz
<% e&~vO| 3w%
CountBean cb=new CountBean(); LGnb"ZN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )/HbmtX qI
CountCache.add(cb); n/W@H Im#
out.print(CountCache.list.size()+"<br>"); [|iWLPO1&k
CountControl c=new CountControl(); +85#`{ D
c.run(); Nq]8p =e
out.print(CountCache.list.size()+"<br>"); 5k:SD7^b
%>