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: r "^{?0
=,aWO7Pz
CountBean.java 5X7kZ!r
O1o.^i$-M
/* 8tc9H}>
* CountData.java FmALmS
* ,|: a7b]
* Created on 2007年1月1日, 下午4:44 sFEkxZi<
* 8e'0AI_>
* To change this template, choose Tools | Options and locate the template under ZOFhX$I
* the Source Creation and Management node. Right-click the template and choose a.|4`*1[;
* Open. You can then make changes to the template in the Source Editor. c=YJ:&/5&
*/ b&$ ?.z
=A6/D
package com.tot.count; `0r=ND5.
X^tVq..0
/** oCLs"L-r{
* 3^LSK7.:
* @author I5"ew=x#
*/ M y:9
public class CountBean { CqXD z
private String countType; -DO*,Eecv
int countId; z.H*"r
/** Creates a new instance of CountData */ lR!Sdd} -
public CountBean() {} (%fl
public void setCountType(String countTypes){ CfMq?.4%E}
this.countType=countTypes; &FWPb#
} _v=@MOI/J
public void setCountId(int countIds){ ]Q\Ogfjp
this.countId=countIds; D_6GzgZ
} :x*8*@kC
public String getCountType(){ Co2* -[R
return countType; Yx_[vLm
} AgsMk
public int getCountId(){ )Oq N\
return countId; {cF7h)j
} \?,'i/c-
} \C3ir &
?VMj;+'tr
CountCache.java @<]xbWhuw
XpzdvR1
/* w;.'>ORC
* CountCache.java ZQvpkO7}M
* mMqT-jT
* Created on 2007年1月1日, 下午5:01 $+IE`(Ckf
* z8bDBoD6
* To change this template, choose Tools | Options and locate the template under
q+{-p?;;
* the Source Creation and Management node. Right-click the template and choose U[zY0B
* Open. You can then make changes to the template in the Source Editor. \lK iUy/
*/ ?Z @FxW
XA~Rn>7&H
package com.tot.count; <z N
import java.util.*; S;$@?vF
/** 9.|+KIRb
* uQN8/Gy*J
* @author 47_4`rzy;
*/ ?~rF3M.=|
public class CountCache { O)MKEMuA
public static LinkedList list=new LinkedList(); ^R.#n[-r2
/** Creates a new instance of CountCache */ iTU8WWY<
public CountCache() {} M/5e4b
public static void add(CountBean cb){ L<>;E
if(cb!=null){ tb7Wr1$<
list.add(cb); #Zpp*S55
} 8<$6ufvOv
} j380=?7
} Qp7|p
cL&V2I5O
CountControl.java Q5e ,[1
/"?y @;Y~
/* omM*h{z$$
* CountThread.java sk~rjH]-g$
* r)<]W@Pr
* Created on 2007年1月1日, 下午4:57 {
p {a0*$5
* Q>nq~#3?
* To change this template, choose Tools | Options and locate the template under &0Zn21q
* the Source Creation and Management node. Right-click the template and choose Ebp^-I9.d
* Open. You can then make changes to the template in the Source Editor. 8NJ(l
*/ @<--5HbX
Nt#zr]Fz
package com.tot.count; ZLdvzH@'
import tot.db.DBUtils; i^(_Gk
import java.sql.*; B^Q\l!r
/** zIWw055W
* krZ J"`
* @author v'B++-%
*/ o)KF+[^
public class CountControl{ DO(-)izC
private static long lastExecuteTime=0;//上次更新时间 Vg/{;uLAe
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1TfK"\
/** Creates a new instance of CountThread */ hS&,Gm`^
public CountControl() {} L)VEA8}
public synchronized void executeUpdate(){ )((Jnm D
Connection conn=null; 2%N$Y]
PreparedStatement ps=null; nBL7LocvR
try{ ~C<
X~$y&
conn = DBUtils.getConnection(); WO$PW`k
conn.setAutoCommit(false); @L^2VVWk^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^ Sx0t
for(int i=0;i<CountCache.list.size();i++){ < pI2}
CountBean cb=(CountBean)CountCache.list.getFirst(); _3h(R`VdWO
CountCache.list.removeFirst(); cTmoz.0
ps.setInt(1, cb.getCountId()); s;q]:+#7g
ps.executeUpdate();⑴ xA]CtB*o7
//ps.addBatch();⑵ <CJua1l\
} gF1qZ=<
//int [] counts = ps.executeBatch();⑶ vpx8GiV
conn.commit(); AwB ]0H
}catch(Exception e){ 1?"vKm
e.printStackTrace(); Eom|*2vWIC
} finally{ `CW8Wj
try{ !<]%V]5[_
if(ps!=null) { W-@A
ps.clearParameters(); ;rpjXP
ps.close(); 9@Yk8
ps=null; ,St#/tu
} b9[;qqq@'
}catch(SQLException e){} &^4\Rx_I
DBUtils.closeConnection(conn); L5""
} Kxz<f>`b/
} 7*y_~H
public long getLast(){ J&S$F:HM
return lastExecuteTime; O>xGH0H
} @HJ&"72$<
public void run(){ =6imrRaaV
long now = System.currentTimeMillis(); $ x
6Rmd{
if ((now - lastExecuteTime) > executeSep) { [o<R#f`
//System.out.print("lastExecuteTime:"+lastExecuteTime); r]?ZXe$;
//System.out.print(" now:"+now+"\n"); {gluK#Qm
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); D61CO-E(D
lastExecuteTime=now; Z5;1ySn{
executeUpdate(); $6h:j#{JE
} =C8 t5BZ"
else{ M*BDrM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7+JQaYO`"
} 4&)*PKq
} ]uX'[Z}t
} q=ZLSBZ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 2V_C_5)1
Y$!K<c k
类写好了,下面是在JSP中如下调用。 `h_,I R<
>>=lh
<% ]K0<DO9
CountBean cb=new CountBean(); UA/Q3)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mv%fX2.
CountCache.add(cb); lz@fXaZM
out.print(CountCache.list.size()+"<br>"); ZO{uG(u
CountControl c=new CountControl(); zx'G0Z9]
c.run(); .MMFN}1O
out.print(CountCache.list.size()+"<br>"); Hv(0<k6oH
%>