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: ^uUA41o`eJ
V{oFig 6
CountBean.java IKP_%R8.
WM|G/'q
/* )r{Wj*u
* CountData.java iZfZF
* Sdmz(R
* Created on 2007年1月1日, 下午4:44 F*J1w|)F0
* DVhBZ!u9
* To change this template, choose Tools | Options and locate the template under "}xIt)n%;
* the Source Creation and Management node. Right-click the template and choose +u$JMp
* Open. You can then make changes to the template in the Source Editor. Pv2uZH(
*/ RN)XIf$@_
9:@Xz5
package com.tot.count; {f`Y\_r$@
}WFI/W'
/** MF'Z?M
* yOEy3d=*
* @author Za!KM
*/ `mteU"{bx
public class CountBean { +ho=0>
private String countType; auAz>6L
int countId; k;cX,*DIn
/** Creates a new instance of CountData */ hu0z
36
public CountBean() {} _J,rql@nG<
public void setCountType(String countTypes){ .qohHJ&
this.countType=countTypes; ;303fS
} cS YCMQ1ro
public void setCountId(int countIds){ 2_ u+&7
this.countId=countIds; QAxy?m,'
} %XukiA+
public String getCountType(){ }(u:K}8
return countType; KPz0;2}
} BZ.l[LMp
public int getCountId(){ e.MyJ:eL
return countId; eC<RM Q4
} JjI1^FRd
} [6RODp3')
&Wa3/mWK
CountCache.java ;
k.@=
i@rUZYF
/* l#v52
* CountCache.java z{ eZsh
b
* D>{`I'
* Created on 2007年1月1日, 下午5:01 kBA.N l7
* SPlt=*C#_
* To change this template, choose Tools | Options and locate the template under dF51_Kk
* the Source Creation and Management node. Right-click the template and choose ~;$QSO\2h
* Open. You can then make changes to the template in the Source Editor. L3oL>r'|
*/ .yfp-n4H
b(|&e
package com.tot.count; :F"IOPfU5[
import java.util.*; <& PU%^Ha
/** =\2gnk~
* am? k
* @author
YMv}]
*/ &@@PJ!&
public class CountCache { Cx~;oWZ
public static LinkedList list=new LinkedList(); 6 M:?W"
/** Creates a new instance of CountCache */ >F7HKwg}Z
public CountCache() {} 6;Z`9PGp
public static void add(CountBean cb){ C;:=r:bth
if(cb!=null){ (=u!E+N
list.add(cb); ~
e?af
} QlB9m2XB
} )=gU~UV
} nU{Qi;0
?0dmw?i
CountControl.java }[|9vF"g.y
/PSXuVtu5
/* L7<30"7
* CountThread.java `-U?{U}H
* LyvR].p=5*
* Created on 2007年1月1日, 下午4:57 Xe&9|M
* %`s#p` Ol1
* To change this template, choose Tools | Options and locate the template under tH0x|
* the Source Creation and Management node. Right-click the template and choose ?QFxds
* Open. You can then make changes to the template in the Source Editor. "9[2vdSX
*/ ,OwTi:yDr
]SAY\;,_
package com.tot.count; qm/>\4eLt
import tot.db.DBUtils; +@fEw
import java.sql.*; :](#W@r
/** h`9 & :zr
* :!t4.ko
* @author i^:#*Q-co
*/ a8)2I~j
public class CountControl{ c oZK
private static long lastExecuteTime=0;//上次更新时间 ,aezMbg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?QKDYH(
/** Creates a new instance of CountThread */ w6>P[oW
public CountControl() {} `'iO+/;GY
public synchronized void executeUpdate(){ ;lE=7[UJ3X
Connection conn=null; #E
Bdg
PreparedStatement ps=null; E7R%G OH
try{ O{c#&/ .K
conn = DBUtils.getConnection(); Pw]+6
conn.setAutoCommit(false); j<
h1s%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 2K/t[.8
for(int i=0;i<CountCache.list.size();i++){ {7oPDP
CountBean cb=(CountBean)CountCache.list.getFirst(); .?APDr"QQH
CountCache.list.removeFirst(); \6 J Y#%
ps.setInt(1, cb.getCountId()); <tZtt9j_
ps.executeUpdate();⑴ 5#|&&$)
//ps.addBatch();⑵ ~kV>nx2
} ;TDvk]:
//int [] counts = ps.executeBatch();⑶ Jo[&y,
conn.commit(); LrO[l0#'Q
}catch(Exception e){ 8q]"CFpa
e.printStackTrace(); +<@1)qZ(E
} finally{ rkWy3X{%2<
try{ 'tkQz
if(ps!=null) { MaPhG<?
ps.clearParameters(); @6~m&$R/
ps.close(); ;,]4A{|
ps=null; k9H}nP$F
} rIB./,
}catch(SQLException e){} X7K{P_5l
DBUtils.closeConnection(conn); ktfxb<%
} J3 oUtu
} Ux^ue9
public long getLast(){ 4IOqSB|
return lastExecuteTime; &x*l{s[
} J80&npsO
public void run(){ n?6^j8i
long now = System.currentTimeMillis(); _?felxG[
if ((now - lastExecuteTime) > executeSep) { %LHt{:9.
//System.out.print("lastExecuteTime:"+lastExecuteTime); njJTEUd">
//System.out.print(" now:"+now+"\n"); 7Cz=;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7~1Fy{tc
lastExecuteTime=now; 89 m.,
executeUpdate(); Z3wdk6%:}
} ^FNju/b
else{ yRQ1Szbjli
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); qh}+b^Wi
} =v?V
} YwH Fn+
} $!p2Kf>/Q
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 @Kt!uKrI
tr0kTW$Ad
类写好了,下面是在JSP中如下调用。 =C(BZ+-^
]YZ_kc^(V;
<% F&7Z(
CountBean cb=new CountBean(); vnbY^ASdw
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t6e6v=.Pg
CountCache.add(cb); IAb.Z+ig
out.print(CountCache.list.size()+"<br>"); t vW0 W
CountControl c=new CountControl(); >#S}J LZ
c.run(); NODg_J~T
out.print(CountCache.list.size()+"<br>"); 4\V/A+<W
%>