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: 6AJk6W^Z
dzOco)y
CountBean.java i`gM> q&
~ZVz
sNrx
/* (s;W>,~q
* CountData.java }dzdx "
* y{@\8B]
* Created on 2007年1月1日, 下午4:44 cOV9g)7^O
* zfKO)Itd
* To change this template, choose Tools | Options and locate the template under OWewV@VXR
* the Source Creation and Management node. Right-click the template and choose HQP.7.w7 5
* Open. You can then make changes to the template in the Source Editor. $,~Ily7w
*/ 1GK.:s6.f
+Xs E
package com.tot.count; > mO*.' Gm
cZBXH*-M!
/** !vf:mMo
* v]( Y n)#
* @author @KL&vm(F$
*/ I #1~CbR
public class CountBean { wU+r]SK@
private String countType; T>asH
int countId; LXo$\~M8G8
/** Creates a new instance of CountData */ Vq+7 /+2"
public CountBean() {} ~g=&wT11
public void setCountType(String countTypes){ Fy{yg]O"
this.countType=countTypes; ikc1,o
} YjDQ`f/
public void setCountId(int countIds){ >Y08/OAI.2
this.countId=countIds; l}/_(*
} !=:>y WQ
public String getCountType(){ *gwaW!=
return countType; gw"cXny
} :o8`2Z *g
public int getCountId(){ eP]y\S*P
return countId; p*c(dkOe8
} I9Ohz!RQ
} our
^J8
}eVDe(7_
CountCache.java Vbv^@Kp
,h o",y
/* 6#U~>r/
* CountCache.java ,<L4tp+y0
* z]N#.utQ
* Created on 2007年1月1日, 下午5:01 Jt5V{9:('
* *:H,-@
* To change this template, choose Tools | Options and locate the template under $^fF}y6N
* the Source Creation and Management node. Right-click the template and choose r[V%DU$dj
* Open. You can then make changes to the template in the Source Editor. @}4>:\es
*/ /FN:yCf
:<P4=P P
package com.tot.count; Trs~KcsD
import java.util.*; +1T>Ob;hk
/** t}R!i-D|HB
* _\d|`3RM
* @author ^)9/Wz _x
*/ [ojL9.6
public class CountCache { aaU4Jl?L
public static LinkedList list=new LinkedList(); VvW4!1Dl
/** Creates a new instance of CountCache */ 6ZIPe~`
public CountCache() {} I+
|uyc
public static void add(CountBean cb){ 7Y@]o=DIc
if(cb!=null){ y0p=E^QM
list.add(cb); W\Pd:t
} -E\G3/*51
} 7=N%$]DKZ
} fh`Y2s|:7R
/UunWZ u%
CountControl.java ]@9W19=P!P
6kp)'wz`
/* OF<:BaRs/
* CountThread.java c<_1o!68
* \9,lMK[b
* Created on 2007年1月1日, 下午4:57 KOe]JDU
* O;4S<N
* To change this template, choose Tools | Options and locate the template under =b$g_+
* the Source Creation and Management node. Right-click the template and choose
&5K3AL
* Open. You can then make changes to the template in the Source Editor. 5P<"I["
*/ h:bx0:O"
tiGH#~?
package com.tot.count; #8t=vb3
import tot.db.DBUtils; 8*8Y\"
import java.sql.*; 2#$7!`6K
/** {s@!N
* H9jlp.F
* @author 1^o})9
*/ 2n>mISy+
public class CountControl{ }2LG9B%
private static long lastExecuteTime=0;//上次更新时间 fV4eGIR&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 P\ P=1NM
/** Creates a new instance of CountThread */ =?Ry,^=b
public CountControl() {} =55)|$hgD
public synchronized void executeUpdate(){ ])y)]H#{
Connection conn=null; ^) s6`:
PreparedStatement ps=null; vrmMEWPV
try{ JUw|nUnl?
conn = DBUtils.getConnection(); 0*]0#2Z
conn.setAutoCommit(false); prO&"t
>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); )Mq4p'*A[
for(int i=0;i<CountCache.list.size();i++){
LT{g^g
CountBean cb=(CountBean)CountCache.list.getFirst(); X_-/j.
CountCache.list.removeFirst(); IrRy1][Qr
ps.setInt(1, cb.getCountId()); "T /$K
ps.executeUpdate();⑴ y+B iaD!U
//ps.addBatch();⑵ 9*j"@Rm
} )X#$G?|Hn
//int [] counts = ps.executeBatch();⑶ v89tV9O)
conn.commit(); "xC$Ko _
}catch(Exception e){ w\
'5lk,"
e.printStackTrace(); M GC=L .
} finally{ 9Q(Lnu
try{ zz3{+1w]
if(ps!=null) { B[sI7D>Y
ps.clearParameters(); evEdFY
ps.close(); S~ckIN]
ps=null; N*m;A6?
} te;bn4~
}catch(SQLException e){} um PN=0u6
DBUtils.closeConnection(conn); @QJPcF"
} i`9}">7v~
} 68~]_r.a
public long getLast(){ 0@'-g^PS
return lastExecuteTime; 0p3) t
} X..M!3W
public void run(){ )sIzBC
long now = System.currentTimeMillis(); {nZP4jze
if ((now - lastExecuteTime) > executeSep) { zwUZ*Se
//System.out.print("lastExecuteTime:"+lastExecuteTime); S5m.oHJI*
//System.out.print(" now:"+now+"\n"); %[*_-%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e#6H[t
lastExecuteTime=now; NB3+kf ,
executeUpdate(); \K2S.j
} 'yOx&~H]
else{ #( 4)ps.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N["M "s(N
} J|V*g]#kP
} :ldI1*@i<
} 3KD:JKn^
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 sFfargl
\SmYxdU'>
类写好了,下面是在JSP中如下调用。 T;kh+i
Ktuv
a3=>N
<% pTQ7woj}
CountBean cb=new CountBean(); _NuHz
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2MXg)GBcU>
CountCache.add(cb); R,!aX"]|
out.print(CountCache.list.size()+"<br>"); _B4N2t$
CountControl c=new CountControl(); L eUp!
c.run(); q2Gm8>F1y.
out.print(CountCache.list.size()+"<br>"); iF##3H$c
%>