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: eR;cl$
G8<,\mg+
CountBean.java Z$+0gm\Cnw
Bh@j6fv
/* N]5-#
* CountData.java ^(a %B
* 0P!6
.-XU
* Created on 2007年1月1日, 下午4:44 QRa>W/N
* !qy/'v4
* To change this template, choose Tools | Options and locate the template under 7
bpV=
* the Source Creation and Management node. Right-click the template and choose :.Np7[~{
* Open. You can then make changes to the template in the Source Editor. 'KXvn0
*/ ,!Q2^R
CM~)\prks
package com.tot.count; B'&%EW]
CjykM])
/** [S*bN!t
* d7l0;yR&+
* @author PiM@iS
*/ r0hu?3u1?
public class CountBean { xy[R9_V
private String countType; #,$d!l @
int countId; 4egq Y0A
/** Creates a new instance of CountData */ &
XcY|y=W
public CountBean() {} 8wwD\1pLS
public void setCountType(String countTypes){ !R4`ihi1
this.countType=countTypes; &{"aD&
} hPH=.rX
public void setCountId(int countIds){ UX(#C,qgG
this.countId=countIds; 9r8*'.K`Z
} 3;#v$F8R
public String getCountType(){ A-4\;[P\
return countType; q *-q5FE
} Li iQ;x
public int getCountId(){ 347p2sK>
return countId; 4WDh8U
} nV
GrW#'E
} 3C2L _ K3
*qGxQ?/
CountCache.java j@Z4(XL
,GGr@})
/* lS9rgq<n
* CountCache.java P b2exS(
* V[Auw3)
* Created on 2007年1月1日, 下午5:01 NtSa#$A
* #(!>
* To change this template, choose Tools | Options and locate the template under lcyan
* the Source Creation and Management node. Right-click the template and choose @/XA*9]l
* Open. You can then make changes to the template in the Source Editor. 91e&-acA
*/ 3fM~R+p
$^d,>hJi
package com.tot.count; Xb3z<r
import java.util.*; L)J0TSh
/** (|"KsGl
* b`fPP{mG
* @author d\D.l^
*/ ^q7
fN0"6
public class CountCache { vt@.fT#e
public static LinkedList list=new LinkedList(); : xB<Rq
/** Creates a new instance of CountCache */ 27G6C`}
public CountCache() {} 0Ocy$
public static void add(CountBean cb){ t%V!SvT8+
if(cb!=null){ 8`kK)iCq
list.add(cb); Mb uD8B
} -dZ7;n5&_
} 0vt?yD
} `/8Dmg
%fo +Y+t
CountControl.java U,~\}$<I
gI<TfcC
/* 5fA<I _ D
* CountThread.java h /@G[5E
* k*[["u^u]
* Created on 2007年1月1日, 下午4:57 @|idlIey
* , 0MDkXb
* To change this template, choose Tools | Options and locate the template under 8|OsVIe%
* the Source Creation and Management node. Right-click the template and choose pMKnA.|
* Open. You can then make changes to the template in the Source Editor. ^ ,d!K2`
*/ u4, p.mZtb
kW3V"twx
package com.tot.count; ^#9
&Rk!t
import tot.db.DBUtils; "VRc R
import java.sql.*; 00[Uk'Q*5
/** n0:'h}^
* oM M`7wJw
* @author HSE9-c=
*/ @GK0j"_
public class CountControl{ /Z94<}C6b
private static long lastExecuteTime=0;//上次更新时间 nGZZCsf <
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %l(qyH)*
/** Creates a new instance of CountThread */ R6r'[-B2
public CountControl() {} Cq(dj^/~m
public synchronized void executeUpdate(){ W
MU9tq[
Connection conn=null; )xy1DA
PreparedStatement ps=null; (:4N#p
try{ #qtAFIm'
conn = DBUtils.getConnection(); a4Qr\"Qm
conn.setAutoCommit(false); ,|<2wn#q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 4RGEg;]S
for(int i=0;i<CountCache.list.size();i++){ @bSxT,2
CountBean cb=(CountBean)CountCache.list.getFirst(); uckag/tv
CountCache.list.removeFirst(); yF8 av=<{
ps.setInt(1, cb.getCountId()); K*xqQ]&
ps.executeUpdate();⑴ P4-`<i]!S
//ps.addBatch();⑵ q;3.pRw(
} N0,wT6.
//int [] counts = ps.executeBatch();⑶ BxS\"W
conn.commit(); ]Nz~4ebB
}catch(Exception e){
0GK<l
e.printStackTrace(); <Wn={1Ts"
} finally{ =*
oFs|v
try{ ^2rNty,nH
if(ps!=null) { s`B]+
ps.clearParameters(); !`LaX!bmp
ps.close(); ,]+P#eXgE
ps=null; k7z;^:
} *NHBwXg+
}catch(SQLException e){} 71_{FL8
DBUtils.closeConnection(conn); }RowAGWL
} Soy!)c]
} =iO K($
public long getLast(){ '/trM %<
return lastExecuteTime; B"rnSui
} yV,ki^^
public void run(){ >RZ]t[)y
long now = System.currentTimeMillis(); {7.."@Ob<v
if ((now - lastExecuteTime) > executeSep) { `z=U-v'H)D
//System.out.print("lastExecuteTime:"+lastExecuteTime); (n_lu=E70
//System.out.print(" now:"+now+"\n"); (LbAP9Zj#f
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u.ubw(vv
lastExecuteTime=now; :L*"OT7(6
executeUpdate(); A[`c2v-hF
} ,\laqH\ 1%
else{ VJmX@zX9
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); >77N5>]e
} xOnbYU
} |WqEJ*$,
} %{WZ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^ ]02)cK
1RpTI7
类写好了,下面是在JSP中如下调用。 v]SHude{
K<TVp;N
<% WDQtj$e+
CountBean cb=new CountBean(); Y /$`vgqs
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); g`I`q3EF)
CountCache.add(cb); 62GP1qH9
out.print(CountCache.list.size()+"<br>"); "Ah (EZAR
CountControl c=new CountControl(); 7N9~nEU
c.run(); #-*7<wN
out.print(CountCache.list.size()+"<br>"); [!H2i
p-
%>