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: tKG;k"wk
'NT#(m%
CountBean.java @)OnIQN~
cyGN3t9`.
/* Tsm1C#6 Y*
* CountData.java JNxW6 cK
* #aitESbT
* Created on 2007年1月1日, 下午4:44 WyBQ{H{So
* QIij>!c4
* To change this template, choose Tools | Options and locate the template under BcZEa^^~os
* the Source Creation and Management node. Right-click the template and choose %z-dM` i
* Open. You can then make changes to the template in the Source Editor. f[JI/H>
*/ Y)Znb;`?a
){O1&|z-
package com.tot.count; qE#&)
qPXANx<^
/** J0?$v6S
* Jw:Fj{D
* @author *=$[}!YG
*/ CdBthOPX)
public class CountBean { 7y>Tn`V8G
private String countType; qa
6=W
int countId; ^i{,z*vi
/** Creates a new instance of CountData */
8qFUYZtY
public CountBean() {} 69[V <1
public void setCountType(String countTypes){ !y>lOw})Q
this.countType=countTypes; E/wQ+rv
} ,_.@l+BM.
public void setCountId(int countIds){ B#HnPUUK
this.countId=countIds; (j8GiJ]{L,
} u;+%Qh
public String getCountType(){ ?G4iOiyt
return countType; $:f.Krj
} Q7CwQi
public int getCountId(){ 6-*~t8
return countId; eZ@Gu
} O%YjWb
}
tSEA999
(@%XWg
CountCache.java _L*f8e8
V~'k1P4
/* uIYcmF\?
* CountCache.java gq
H`GI
* (oLpnjJ(,
* Created on 2007年1月1日, 下午5:01
I6K7!+;2
* ,pDp>-vI%
* To change this template, choose Tools | Options and locate the template under 3
R5%N
~
* the Source Creation and Management node. Right-click the template and choose lp:_H-sG
* Open. You can then make changes to the template in the Source Editor. u{g]gA8s
*/ 8s QQK.N(
&q4ox7 1
package com.tot.count; /QrA8
import java.util.*; CCuxC9i7
/** 8_"3Yb`f
* "NxOOLL
* @author zo_k\K`{@
*/ #C"7
l6'a
public class CountCache { fzLANya
public static LinkedList list=new LinkedList(); E/:+@'(k
/** Creates a new instance of CountCache */ `[X6#`<
public CountCache() {} 536^PcJlN
public static void add(CountBean cb){ S8*^ss>?^R
if(cb!=null){ lP}o[Rd
list.add(cb); 8BHL
} _TZW|Dh-2F
} ,"@w>WL<9
} |tG05 +M
D4AEZgC F,
CountControl.java IgLVn<5n
nped
/* 'GrRuT<
* CountThread.java ?$<SCN=
* d-hbvLn
* Created on 2007年1月1日, 下午4:57 jVX._bEGX
*
s0gJ f[
* To change this template, choose Tools | Options and locate the template under n)tU9@4Np
* the Source Creation and Management node. Right-click the template and choose B:e.gtM5
* Open. You can then make changes to the template in the Source Editor. vAi"$e
*/ vz6SCGg,
JR/W9i
package com.tot.count; ktN%!Mh\
import tot.db.DBUtils; 1pWk9Xuh
import java.sql.*; "=9-i-K9B
/** .JNcY]V#
* A)OdQFet(
* @author 1lbwJVY[
*/ qO7fbql_
public class CountControl{ +<gg
private static long lastExecuteTime=0;//上次更新时间 l<$rqz3D
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ';_1rh
/** Creates a new instance of CountThread */ Po!oN~r
public CountControl() {} =nLO?qoe
public synchronized void executeUpdate(){ \.5F](:
Connection conn=null; .H ,pO#{;
PreparedStatement ps=null; ex.+'m<g
try{ &8Zeq3~
conn = DBUtils.getConnection(); 3b#L17D3_
conn.setAutoCommit(false); /d[Mss
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7`Qde!+C
for(int i=0;i<CountCache.list.size();i++){ TKK,Y{{
CountBean cb=(CountBean)CountCache.list.getFirst(); 1d`cTaQ-
CountCache.list.removeFirst(); JK[T]|G
ps.setInt(1, cb.getCountId()); pV8[l) J
ps.executeUpdate();⑴ T]^?l
//ps.addBatch();⑵ $6 W3EOl
} FU[*8^Z
//int [] counts = ps.executeBatch();⑶ a-fv[oB
conn.commit(); Og+)J9#
}catch(Exception e){ bdCykG-
e.printStackTrace(); x,w8r+~5
} finally{ w_\nB}_
try{ YmOldR9v(
if(ps!=null) { "";=DH
ps.clearParameters(); J)_>%.
ps.close(); M
Z2^@It
ps=null; PVhik@Yoh
} @]*[c})/
}catch(SQLException e){} # ?_#!T|
DBUtils.closeConnection(conn); nQ|GqU\oA
} V)=Z6 ti
} )W#T2Z>N1
public long getLast(){ Xj%,xm>}!u
return lastExecuteTime; 5Wo5n7o
} YDW|-HIF
public void run(){ g#w`J\iz
long now = System.currentTimeMillis(); s}s|~
if ((now - lastExecuteTime) > executeSep) { k<!<<,Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); (9E( Q*J5x
//System.out.print(" now:"+now+"\n"); 2H6:np|O
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \/n+j!
lastExecuteTime=now; 7vw;Egd@@-
executeUpdate(); f#1/}Hq/I
} Cc2MYm8
else{ :Pc(DfkS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); [M`=HhJ4
} d<!IGt4Ky
} sp^Wo7&g
} UAdz-)$
//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 |4Qx=x>
<Kg2$lu(_`
类写好了,下面是在JSP中如下调用。 ><cU7 ja[^
hzv3F9.x
<% v_.HGGS
CountBean cb=new CountBean(); 0JK2%%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +N7"EROc
CountCache.add(cb); w\Iqzpikr
out.print(CountCache.list.size()+"<br>"); vf[&7n
CountControl c=new CountControl(); ![
a
c.run(); dIvy!d2l
out.print(CountCache.list.size()+"<br>"); RJ@\W=aZ
%>