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: PU2^4h/[`
B{lj.S`mB
CountBean.java Bc*FH>E
&|K9qa~)Y
/* `6:B0-r
* CountData.java {zTnE?(o`
* z}a9%Fb
* Created on 2007年1月1日, 下午4:44 fjd)/Gg
* =G9I7Y@
* To change this template, choose Tools | Options and locate the template under rk-GQ#SKU
* the Source Creation and Management node. Right-click the template and choose fpa~~E-
* Open. You can then make changes to the template in the Source Editor. (uVL!%61k
*/ FTQNS8
mz|p=[lR|
package com.tot.count; !kS/Ei
|pG%]?A
/** Q@
Ze+IhK`
* X5tx(}j
* @author dLfB){>S
*/ KK}ox%j
public class CountBean { VTwDa*]AhB
private String countType; 6dncUfB
int countId; oMNSQMlI
/** Creates a new instance of CountData */ T' > MXFLh
public CountBean() {} Z0[d;m*
public void setCountType(String countTypes){ v{X<6^g
this.countType=countTypes; .%EYof
} 2}n7f7[/b
public void setCountId(int countIds){ \2^o,1r/
this.countId=countIds; +'$5Jtz
} :>y;*x0w
public String getCountType(){ X`fb\}~R(
return countType; ka_(8
} t$e' [;w
public int getCountId(){ WDi2m"
return countId; +ag_ w}
} q-s(2C
} `=$p!H8
FuM:~jv
CountCache.java KL yI*`
ALQ-aXJ
/* {2)).g
* CountCache.java Xp.$FJ1)
* klR\7+lK
* Created on 2007年1月1日, 下午5:01 ^
-4~pDv^
* 9:P\)'y?
* To change this template, choose Tools | Options and locate the template under <L+1
&H
* the Source Creation and Management node. Right-click the template and choose MD^,"!A
* Open. You can then make changes to the template in the Source Editor. 5eiKMKW[
*/ I^Dm 3yz
N8iLI`
package com.tot.count; ?>Ngsp>-P
import java.util.*; 2?{'(iay
/** 9:*[Q"v
* _= cU2
* @author jV[;e15+
*/ 8iTB
public class CountCache { !FwNq'Q8$
public static LinkedList list=new LinkedList(); 4f&"1:
/** Creates a new instance of CountCache */ pm=m~
public CountCache() {} .8->n aj|
public static void add(CountBean cb){ J&iSS9c
if(cb!=null){ _X|prIOb=
list.add(cb); 2EOx],(|
} Z9.0#Jnu
} :(\JY?+w
} {_mVfFG
G
c\^Kg^#
CountControl.java UwxszEHC
}<YU4EW
/* P{x6e/
* CountThread.java SpImd IpD
* ):[}NDmC
* Created on 2007年1月1日, 下午4:57 p|(SR~;6
* HB{'MBs
* To change this template, choose Tools | Options and locate the template under OD9z7*E@
* the Source Creation and Management node. Right-click the template and choose !,dp/5
V
* Open. You can then make changes to the template in the Source Editor. XF+4*),
*/ O}w%$ mq
I tb_ H
package com.tot.count; YS#*#!ZMn?
import tot.db.DBUtils; )Gm9x]SVl
import java.sql.*; BA2J dU
/** 3FtL<7B'.
* \_
* @author 9;'#,b*(
*/ IJ~j(.W
public class CountControl{ 8ok=&Gq4
private static long lastExecuteTime=0;//上次更新时间 Vef!5]t5
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 l2kGFgc
/** Creates a new instance of CountThread */ DJ DQH \&
public CountControl() {} h!ogH >S~
public synchronized void executeUpdate(){ damG*-7Svx
Connection conn=null; |j-ng;
PreparedStatement ps=null; $_iE^zZaU^
try{ 4&=</ok6`0
conn = DBUtils.getConnection(); v3aPHf
conn.setAutoCommit(false); DR{O.TX
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @({=~
W^
for(int i=0;i<CountCache.list.size();i++){ 7nPcm;Er
CountBean cb=(CountBean)CountCache.list.getFirst(); F}7sb#G
CountCache.list.removeFirst(); 5.*,IedY
ps.setInt(1, cb.getCountId()); lKB9n}P
ps.executeUpdate();⑴ l^d' 8n
//ps.addBatch();⑵ i!RfUod
} lm
96:S
//int [] counts = ps.executeBatch();⑶ S2e3d
conn.commit(); _3:%b6&Pz
}catch(Exception e){ ``P9fd
e.printStackTrace(); ,l6,k<
} finally{ 71y{Dwya
try{ +ZwoA_k{
if(ps!=null) { A.Wf6o
ps.clearParameters(); 2Kf/I d1
ps.close(); ^;'8yE/
ps=null; "p*'HQ
} xnt) 1Q
}catch(SQLException e){} |?#JCG
DBUtils.closeConnection(conn); A[8m3L#k
} #-\5O
} DnFzCJ
public long getLast(){ +C8O"
return lastExecuteTime; ZMb+sUK
} *!ng)3#
public void run(){ Ps>:|j+
long now = System.currentTimeMillis(); 9OV@z6
if ((now - lastExecuteTime) > executeSep) { YR*gOTD
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0cE9O9kE
//System.out.print(" now:"+now+"\n"); 0U@#&pUc
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }L)[>
lastExecuteTime=now; GTM0Qvf?
executeUpdate(); ;aV3j/
} L FkDb}
else{ 5h&sdzfG
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); aZ4?!JW .
} 9-/q-,
} aTTkj\4
} RARA _tii
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 VaY#_80$s
k9f|R*LM
类写好了,下面是在JSP中如下调用。 (0H=f6N
|67Jw2
<% mLqqo2u
CountBean cb=new CountBean(); j(Lz& *4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t\hnnu`Pq
CountCache.add(cb); Yu\$Y0 {]
out.print(CountCache.list.size()+"<br>"); N?ccG\t
CountControl c=new CountControl(); R\5,H!V9n
c.run(); Cd_@<
out.print(CountCache.list.size()+"<br>"); Ai1"UYk\\Y
%>