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: Vi$-Bw$@
07hF2[i
CountBean.java ~ Uo)0
]TaN{"
/* 72,rFYvpK
* CountData.java EKp@9\XBC
* \.g\Zib )
* Created on 2007年1月1日, 下午4:44 @UdfAyL
* lqb/eN9(t
* To change this template, choose Tools | Options and locate the template under IVW1]y
* the Source Creation and Management node. Right-click the template and choose ,<2DLp%%D
* Open. You can then make changes to the template in the Source Editor. w/L `
*/ TFcT3]R[rL
}E_#k]#*
package com.tot.count; \8uIER5)
)+Oujt
/** h`MF#617
* _wdG|{px
* @author pNRk.m]
*/ "gD-8C3
public class CountBean { %r+vSGt;5
private String countType; F9*g=
int countId; p7H3J?`w1+
/** Creates a new instance of CountData */ TW^/sx
public CountBean() {} Lq>&d,F06)
public void setCountType(String countTypes){ PpsIhMq@
this.countType=countTypes; @ps1Dr4s
} 1 tR_8lC
public void setCountId(int countIds){ UswZG^Wh
this.countId=countIds; Zec <m8~
} 6b!F 1
public String getCountType(){ JBnKK
return countType; ~g7l8H67
} "4%"&2L
public int getCountId(){ *]i!fzI']
return countId; 5 Qoew9rA
} b2@VxdFN
} NuU9~gSQ
DvM5 k
CountCache.java 98.>e
KeNL0_Pw
/* sFBneBub
* CountCache.java 1[]&(Pa
* vp(;W,ba:|
* Created on 2007年1月1日, 下午5:01 #b7$TV
* *kIc9}
* To change this template, choose Tools | Options and locate the template under =f(cH152T
* the Source Creation and Management node. Right-click the template and choose $TI5vhQ
* Open. You can then make changes to the template in the Source Editor.
U8(Nk\"X\
*/ jg&E94}+
;us%/kOR
package com.tot.count; ",)Qc!^P$
import java.util.*; jV8q)=}*)
/** hkOsm6
* "l >Igm
* @author 4Bl{WyMJ |
*/ `
}3qhar
public class CountCache { yAN=2fZm
public static LinkedList list=new LinkedList(); ?3O9eZY@
/** Creates a new instance of CountCache */ eznypY=
public CountCache() {} W0=O+0$^
public static void add(CountBean cb){ 9!><<7TS
if(cb!=null){ MaD3[4@#
list.add(cb); 3z]+uv+2J
} R=Tqj,6
} iZZ (4
} 0 P[RyQI
?2Kt'1s#
CountControl.java =tU{7i*+
j w* IO
/* S"wg2X<
* CountThread.java .Q)|vq^
* K\)Td+~jc
* Created on 2007年1月1日, 下午4:57 kg`.[{k
* >Yt/]ta4+
* To change this template, choose Tools | Options and locate the template under s[gKc '
* the Source Creation and Management node. Right-click the template and choose XW?b\!@ $
* Open. You can then make changes to the template in the Source Editor. (Y^X0yA/
*/ z5bo_Eq
"@9?QI}
package com.tot.count; <9sO
import tot.db.DBUtils; 3v")J*t
import java.sql.*; }$\M{#C~
/** ?EX"k+G
* MC,>pR{
* @author H'qG/@u-l
*/ =YG _z^'
public class CountControl{ Z#.f&K )xX
private static long lastExecuteTime=0;//上次更新时间 45&8weXO:'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 H_?o-L?+
/** Creates a new instance of CountThread */ *H[Iq!@
public CountControl() {} +ht|N[P
public synchronized void executeUpdate(){ YJ:3!B>Zo
Connection conn=null; +ki{H}G21
PreparedStatement ps=null; ,&4qgp{)
try{ <58l;<0
conn = DBUtils.getConnection();
{NJfNu
conn.setAutoCommit(false); Ix|~f1*%
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); '$ef+@y
for(int i=0;i<CountCache.list.size();i++){ {m`A!qcD|
CountBean cb=(CountBean)CountCache.list.getFirst(); 0 'Vg6E]/
CountCache.list.removeFirst(); s`Cy
a`
ps.setInt(1, cb.getCountId()); "G:<7oTa
ps.executeUpdate();⑴ {iG@U=>
//ps.addBatch();⑵ 3zT_^;:L
} |;A/|F0-e
//int [] counts = ps.executeBatch();⑶ Db"DG(
conn.commit(); ;#MB7A
}catch(Exception e){ al+ #y)+
e.printStackTrace(); @t1V
o}c
} finally{ 1.q_f<U
try{ *6BThvg|&X
if(ps!=null) { z>R#H/h+
ps.clearParameters(); Q o =Kqv
ps.close(); yFhB>i
ps=null; e5Mln!.o
} d`d0N5\
}catch(SQLException e){} W9oAjO NE
DBUtils.closeConnection(conn); \ (p{t
} ,_ag;pt9)
} |Oag,o"
public long getLast(){ p
h[\)
return lastExecuteTime; !6}O.Nu
} IHC1G1KW=A
public void run(){ :D7|%KK
long now = System.currentTimeMillis(); g+PPW88P;
if ((now - lastExecuteTime) > executeSep) { TEsnN i
1
//System.out.print("lastExecuteTime:"+lastExecuteTime); D7"p}PD>~
//System.out.print(" now:"+now+"\n"); [i]r-|_K
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); k'_ P7
lastExecuteTime=now; $OVXk'cc
executeUpdate(); xLZd!>C
} #%@MGrsK
else{ u-"c0@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -=698h*
} ]S 7^ITn
} 0J~Qq]g
} iq*A("pU
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 UofTll)
^zEE6i
类写好了,下面是在JSP中如下调用。 7~M<cD
<:8,niKtw
<% 6D;^uM2N
CountBean cb=new CountBean(); zdSh:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 0iEa[G3
CountCache.add(cb); 0@Kkl$O>mb
out.print(CountCache.list.size()+"<br>"); irTv4ZE'+l
CountControl c=new CountControl(); 0uCT+-
c.run(); vw<K}z
out.print(CountCache.list.size()+"<br>"); Tp<k<uKD
%>