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: @?2n]n6
v@T'7?s.
CountBean.java vC9@,[
/jrY%C
/* rFXSO=P?Z
* CountData.java gM_:l
* T_L6 t66I
* Created on 2007年1月1日, 下午4:44 G8NRj9k?
* ^!>.97*
* To change this template, choose Tools | Options and locate the template under 0 K3Hf^>m
* the Source Creation and Management node. Right-click the template and choose ^eTZn[qH>w
* Open. You can then make changes to the template in the Source Editor. e`DsP8-&v
*/ Ysk,w,K
aG3k4
package com.tot.count; 1=TSJ2{9
DJ:38_ F
/** ~PUsgL^
* x*mc - &N
* @author |(%AM*n
*/ !V(`ZH
public class CountBean { u&3EPu
private String countType; j6X LyeG7
int countId; G^"H*a
/** Creates a new instance of CountData */ Rrz'(KSDw
public CountBean() {} ~x+Ykq0
public void setCountType(String countTypes){ S_T
this.countType=countTypes; FH
-p!4+]
} ;l`X!3
public void setCountId(int countIds){ {F)E\)$G
this.countId=countIds; (6#M9XL
} AFtCqq#[
public String getCountType(){ W%zmD Hk~
return countType; T+BIy|O
} w&+\Wo;([b
public int getCountId(){ )6C`&Mj
return countId; b60[({A\s&
} 5\+EHW!o
} )T<D6l
Lt
:>ZzP: QD
CountCache.java 1bDJ}M~]z
.='3bQ(UZ4
/* CMKhS,,o
* CountCache.java Ku&*`dME
* Dwk$CJb3-
* Created on 2007年1月1日, 下午5:01 rN'.&;Y5
* ~\-r
* To change this template, choose Tools | Options and locate the template under _H/67dcz,
* the Source Creation and Management node. Right-click the template and choose mj,qQ=n;p
* Open. You can then make changes to the template in the Source Editor. 1O- E],
*/ zdT ->%
t3Qm-J}wSB
package com.tot.count; 3P3:F2S R
import java.util.*; zv|M*Wu
/** SkriX\p
* ]zy~@,\
* @author #Ul4&QVeg
*/ T:dX4=z
public class CountCache { A&;EV#]ge
public static LinkedList list=new LinkedList(); '[n)N@h
/** Creates a new instance of CountCache */ olHH9R9:
public CountCache() {} %h3L
public static void add(CountBean cb){ X!2.IsIS8
if(cb!=null){ KuU3DTS85Z
list.add(cb); QR|XV%$
} 9PUa?Bc`=
} Q*,6X*W!~
} Rd .U;>
?' TA!MR
CountControl.java -??!@R7V
Y>(ZsHu
/* uT'-B7N
* CountThread.java (QA-"9v#i,
* :~WPY9i`
* Created on 2007年1月1日, 下午4:57 $^!a`Xr
* x:=0.l#
* To change this template, choose Tools | Options and locate the template under rsd2v9
* the Source Creation and Management node. Right-click the template and choose }g%KvYB_
* Open. You can then make changes to the template in the Source Editor. m]{<Ux
*/ v; je <DT
$'WapxF
package com.tot.count; 2]?w~qjWm
import tot.db.DBUtils; E`A<]dAoK
import java.sql.*; L*kh?PS;
/** o+]Y=r2
* D2>hMc
* @author ?ZSXoy-kr
*/ ?|%\<h@;
public class CountControl{ ckH$E%j
private static long lastExecuteTime=0;//上次更新时间 K> c8r8!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x`};{oz;
/** Creates a new instance of CountThread */ g;u<[>'I
public CountControl() {} ?Zc/upd:$N
public synchronized void executeUpdate(){ N#<zEAB
Connection conn=null; v9j4|w
PreparedStatement ps=null; */0vJz%<.M
try{ d,GtH)( s
conn = DBUtils.getConnection(); 4jC4X*
conn.setAutoCommit(false); : ;E7+m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n"^/UQ|#j
for(int i=0;i<CountCache.list.size();i++){ LUe>)eqw
CountBean cb=(CountBean)CountCache.list.getFirst(); m &0(%
CountCache.list.removeFirst(); hQd@bN8
ps.setInt(1, cb.getCountId()); i6!T`Kau
ps.executeUpdate();⑴ Q1O_CC}
//ps.addBatch();⑵ $UFge%`,q@
} PV,kYM6
//int [] counts = ps.executeBatch();⑶ 3*X,{%
conn.commit(); I,C AFq
}catch(Exception e){ 78^UgO/
e.printStackTrace(); Zq\RNZ}
} finally{ Z1)jRE2dl
try{ z*NC?\
if(ps!=null) { $'J6#Vs
ps.clearParameters(); okK/i
ps.close(); ,w9#%=xE
ps=null; QoT3;<r}
} h X>VVeIZ
}catch(SQLException e){} ] dm1Qm
DBUtils.closeConnection(conn); }rj C_q
} k *G!.
} K#JabT
public long getLast(){ &.+n
L
return lastExecuteTime; azR;*j8Q'
} (^s &M
public void run(){ 9QX~aX
long now = System.currentTimeMillis(); T/WmS?
if ((now - lastExecuteTime) > executeSep) { N SxPN:
//System.out.print("lastExecuteTime:"+lastExecuteTime); OUIUgej
//System.out.print(" now:"+now+"\n"); 4mM2C`I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HP4'8#3o
lastExecuteTime=now; <.A C=4@V
executeUpdate(); 23(E3:.
} xtIehr0{$I
else{ U&]p!DV&;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); fbzKO^Ub
} wEHAkc)Q
} |=^#d\?]j
} xM'S
;Sg
//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 Kl46CZs#8
)v!lP pe8
类写好了,下面是在JSP中如下调用。 8[`^(O#\E
jL7MmR#y5"
<% '4^V4i
CountBean cb=new CountBean(); ExOB P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); z:i X]df
CountCache.add(cb); TOPPa?=vk
out.print(CountCache.list.size()+"<br>"); f5=t*9_-[
CountControl c=new CountControl(); {Hp}F!X$
c.run(); 49J+&G?)j
out.print(CountCache.list.size()+"<br>"); n?P 5pJ
%>