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: D,xWc|V
$o\p["DP
CountBean.java 3iYz<M
yWIieztp
/* GG"0n{>0
* CountData.java Js+d4``W
* ^FgNg'"[3
* Created on 2007年1月1日, 下午4:44 !~UI~-i'
*
OfTcF_%
* To change this template, choose Tools | Options and locate the template under xmKa8']x
* the Source Creation and Management node. Right-click the template and choose j-gLX
* Open. You can then make changes to the template in the Source Editor. ;TSnIC)c
*/ 2BH>TmS
a2/r$Tgm
package com.tot.count; <6<uO\B\
jbIWdHZ/US
/** Z.6`O1OY}?
* wdBytH6r.
* @author ?3SlvKI}H`
*/ $ajw]2kx
public class CountBean { e"r'z
n
private String countType; UQ|0Aqwq
int countId; M0Z>$Az]t
/** Creates a new instance of CountData */ _WK+BxH
public CountBean() {} 2?t(%uf]
public void setCountType(String countTypes){ e::5|6x
this.countType=countTypes; ORQGay
} iN<5[ztd
public void setCountId(int countIds){ 6?*iIA$b
this.countId=countIds; SJU93n"G/
} n!Y.?mU6
public String getCountType(){ ("/*k
return countType; $O}gl Q
} IX7d[nm39
public int getCountId(){ Ccz:NpK+
return countId; ';aPoaO %
} x(}t r27o
} p5F[( H|9
^%_B'X9
CountCache.java /<:9NP'^
;x^&@G8W`
/* EoU}@MjM~
* CountCache.java ;ok];4`a
* 5B'-&.Aj+
* Created on 2007年1月1日, 下午5:01 %c^]Rdl
* IUd>jHp`6
* To change this template, choose Tools | Options and locate the template under ItM?nyA
* the Source Creation and Management node. Right-click the template and choose KH pxWq
* Open. You can then make changes to the template in the Source Editor. KXw
\N!
*/ x?CjRvT$
uzp!Y&C
package com.tot.count; ]?``*{Zqy
import java.util.*; qgZ(o@\
/** @TgCI`E
* e}[$ =
* @author 4]
?
*/ yE"hgdL
public class CountCache { )W 57n)]
public static LinkedList list=new LinkedList(); d1y(Jt
/** Creates a new instance of CountCache */ -HoPECe
public CountCache() {} J=zZGd%
public static void add(CountBean cb){ GQF7]j/
if(cb!=null){ ?9?0M A<[i
list.add(cb); X0vkdNgW
} &)s
A(
} SNK+U"Q
} AZl=w`;/O%
xmiF!R
CountControl.java R63"j\0
&<_sXHg<x
/* iZjvO`@[
* CountThread.java ][G<CO`k
* t:=Ui/!q
* Created on 2007年1月1日, 下午4:57 O')Ivm,E
* Kq{s^G
* To change this template, choose Tools | Options and locate the template under f7s]:n*Ih
* the Source Creation and Management node. Right-click the template and choose P\2QH@p@t
* Open. You can then make changes to the template in the Source Editor. q,:\i+>K*
*/ 9,y&?GLP
42m`7uQ
package com.tot.count; 8 6L&u:o:
import tot.db.DBUtils; *EV] 8
import java.sql.*; _^a.kF
/** h@W}xT
* |d%Dw^
* @author ;7m>40W
*/ =z=Guvcn`
public class CountControl{ kOtC(\]5
private static long lastExecuteTime=0;//上次更新时间 tOspDPSXX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 gVG :z_6
/** Creates a new instance of CountThread */ "r"Y9KODm
public CountControl() {} ; $y.+5 q
public synchronized void executeUpdate(){ Ro-Mex2
Connection conn=null;
xY!]eLZ)&
PreparedStatement ps=null; 3I"&Qp%2
try{ K]
Eq"3
conn = DBUtils.getConnection(); k.lnG5e
conn.setAutoCommit(false); mD )Nh
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E#HO0]S
for(int i=0;i<CountCache.list.size();i++){ &)bar.vw/
CountBean cb=(CountBean)CountCache.list.getFirst(); %{HqF>=~
CountCache.list.removeFirst(); :=i0$k<E/
ps.setInt(1, cb.getCountId()); /au\OBUge
ps.executeUpdate();⑴ L3<XWpv
//ps.addBatch();⑵ hlUF9}
} Nju7!yVM_
//int [] counts = ps.executeBatch();⑶ QT|m N
conn.commit(); CS"p[-0
}catch(Exception e){ %djx0sy
e.printStackTrace(); ! prU!5-
} finally{ Upv2s:wa}z
try{ .IKK.G
if(ps!=null) { _&dGo(B
ps.clearParameters(); BV!Kiw
ps.close(); `E|IMUB~
ps=null; cA/2,i
} ;bAy7
}catch(SQLException e){} {Ua5bSbh
DBUtils.closeConnection(conn); {X"X.`p
} 8"<!8Img
} D6ck1pxkx
public long getLast(){ x65e,'
return lastExecuteTime; N`zHe*=[~
} !4 hs9b
public void run(){ @x=CMF15
long now = System.currentTimeMillis(); "n8_Ag@r
if ((now - lastExecuteTime) > executeSep) { Zy!\=-dSm
//System.out.print("lastExecuteTime:"+lastExecuteTime); ~Yr.0i.W
//System.out.print(" now:"+now+"\n"); (>8fcQUBb
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N@A#e/8
lastExecuteTime=now; IsRsjhg8x
executeUpdate(); @ym7hk.
} Yb?#vp I
else{ ,U2D&{@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); \/$v@5
} F(XWnfUv
} &pmJ:WO,h
} hqBwA1](a
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 |RjjP 7
\4vFEJSh
类写好了,下面是在JSP中如下调用。 =Wjm_Rvk9
>yWJk9hf
<% +'KM~c?]
CountBean cb=new CountBean(); Zv-6H*zM6
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
k,@1rOf
CountCache.add(cb); C u?$!|V
out.print(CountCache.list.size()+"<br>"); tP:xx2N_
CountControl c=new CountControl(); DX!$k[
c.run(); 6g.@I!j E
out.print(CountCache.list.size()+"<br>"); )b-G2< kb
%>