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: lv9Tq5C
zXD/hM
CountBean.java h8X[*Wme
XwFTAaZ
/* .]s? 01Z
* CountData.java b$yIM
* -DK6(<:0
* Created on 2007年1月1日, 下午4:44 %P D}VF/Y
* uVKe ?~RC
* To change this template, choose Tools | Options and locate the template under 9!FU,4 X
* the Source Creation and Management node. Right-click the template and choose KJ:z\N8eo
* Open. You can then make changes to the template in the Source Editor. yjsj+K
pL
*/ "{ \xBX~oM
{Wi*B(
package com.tot.count; H6{Bx2J1*
'&e8;X
/** 7e\Jg/FU
* |'z24 :8
* @author qS9<_if2
*/ D'vaK89\
public class CountBean { 7B=VH r
private String countType; zjh:jrv~
int countId; WMC\J(@.
/** Creates a new instance of CountData */ T0Xm}i
public CountBean() {} ;i\N!T{>
public void setCountType(String countTypes){ ^2);*X>
this.countType=countTypes; GcDA0%i
} Hqs!L`oW)
public void setCountId(int countIds){ 9cHo~F|ur
this.countId=countIds; Rk7F;2
} K1^7v}P
public String getCountType(){ w^Yo)"6
return countType; Vjs'|%P7
} {kw%7}!
public int getCountId(){ ~\<$H'
return countId; }I-nT!D'y
} 3}!u8,P
} tjt^R$[ @
pS|K[:5
CountCache.java ;N?(R\*8
|9=A"092{
/* &+&@;2
* CountCache.java LRts
W(A/
* !^&VZh
* Created on 2007年1月1日, 下午5:01 9:Oz-b
* f}"eN/T
* To change this template, choose Tools | Options and locate the template under 3>^]r jFw
* the Source Creation and Management node. Right-click the template and choose 2|=hF9
* Open. You can then make changes to the template in the Source Editor. PPH;'!>s"
*/ ch:rAx
&3Yj2Fw
package com.tot.count; u*):
D~A
import java.util.*; } 6!/Nb
/** kl]MP}wc
* h x&"f e
* @author )v_v 7 ~H&
*/ ,}&TZkN{-
public class CountCache { %4),P(4N
public static LinkedList list=new LinkedList(); YI
?P@y
/** Creates a new instance of CountCache */ eA86~M?<o
public CountCache() {} Rx&O}>"E>l
public static void add(CountBean cb){ DqT<bNR1*;
if(cb!=null){ Y(bB7tR
list.add(cb); r'j88)^
} ij;NM:|Sd
} \fUX_0k9,
} nAWb9Yk
n0T|U
CountControl.java S4`X^a}pY
@B(oq1i@
/* 8T9s:/%
* CountThread.java Bh'fkW3
* @,GL&$Y:W
* Created on 2007年1月1日, 下午4:57 \Q(a`6U
* P*BRebL:
* To change this template, choose Tools | Options and locate the template under lYCvYe
* the Source Creation and Management node. Right-click the template and choose -f&vH_eK
* Open. You can then make changes to the template in the Source Editor. !5(DU~S*@S
*/ 4pf@.ra,
0t%]z!
package com.tot.count; p|.5;)%|
import tot.db.DBUtils; On}1&!{1]
import java.sql.*; $QwpoVp`~
/** /nQuM05*Z
* 6" * <0
* @author OQ hQ!6
*/ #jW -&a
public class CountControl{ I2WP/
private static long lastExecuteTime=0;//上次更新时间 TDDMx |{
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 yy=hCjQ)
/** Creates a new instance of CountThread */ $
mE*=
public CountControl() {} U%s@np
public synchronized void executeUpdate(){ !(F?`([A
Connection conn=null; HzGwO^tbK
PreparedStatement ps=null; UjQz
try{ _\X ,a5Un
conn = DBUtils.getConnection(); sdZ$3oE.
conn.setAutoCommit(false); BP@tI|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P?/JyiO}
for(int i=0;i<CountCache.list.size();i++){ 'Og@<~/Xy
CountBean cb=(CountBean)CountCache.list.getFirst(); ?LmeZ}K
CountCache.list.removeFirst(); Bh2l3J4X
ps.setInt(1, cb.getCountId()); Hvm}@3F|
ps.executeUpdate();⑴ h;jO7+W
//ps.addBatch();⑵ 3
R+e
} ah:["< z<
//int [] counts = ps.executeBatch();⑶ b(GV4%
conn.commit(); dT*Yv`h
}catch(Exception e){ ZI!:
e.printStackTrace(); }6%XiP|
} finally{ 4T(d9y
try{ O*l,&5
if(ps!=null) { }x`Cnn
ps.clearParameters(); H]R/=OYBUh
ps.close(); GNMOHqg4
ps=null; XQ}J4J~Vm
} |-}.Y(y
}catch(SQLException e){} NplyvjQN;
DBUtils.closeConnection(conn); &M}X$k I
} 5OI.Ka
} isL
zgN%
public long getLast(){ q7Hf7^a
return lastExecuteTime; _x<NGIz
} g77M5(ME
public void run(){ sQ#e 2
long now = System.currentTimeMillis(); =0d|F
8
if ((now - lastExecuteTime) > executeSep) { n8<?<-2
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9)1Ye
//System.out.print(" now:"+now+"\n"); j+gxn_E
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); =|z:wlOs
lastExecuteTime=now; ]##aAh-P4&
executeUpdate(); hU""YP~y
} 9KU&M"Yq&i
else{ #
-luE
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^qR|lA@=\
} 4n1g4c-
} _M`ZF*o=c
} "iK=
8
//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 q-<DYVG+
4tZ *%!I'
类写好了,下面是在JSP中如下调用。 ~gd#cL%
:E.a.-
<% !.,wg'\P
CountBean cb=new CountBean(); Njg$~30
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); I@KM2KMN
CountCache.add(cb); g4h{dFb|_
out.print(CountCache.list.size()+"<br>"); oN,1ig
CountControl c=new CountControl(); gQ{ #C'
c.run(); rpRyB9
out.print(CountCache.list.size()+"<br>"); JLE&nbKS
%>