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: j<4J_wE
Hk(w\
CountBean.java M"ZP s
+u:8#!X$RD
/* *~4w%U4T0
* CountData.java WUMx:a0!
* i8+kc_8#d
* Created on 2007年1月1日, 下午4:44 No!P?
* Ds$FO}KD{
* To change this template, choose Tools | Options and locate the template under q$0^U{j/
* the Source Creation and Management node. Right-click the template and choose p;U[cGHC
* Open. You can then make changes to the template in the Source Editor. C.FGi`rrm
*/ `N;u#z
;9/6X#;$
package com.tot.count; O=G2bdY{,
YLJH?=2@
/** v93+<@Z
* -;_NdL@
* @author aG?'F`UQ
*/ E_/v$
public class CountBean { yIh>j.P
private String countType; &l-g3l[
int countId; lD _
u
/** Creates a new instance of CountData */ QaUh+k<6
public CountBean() {} ;XZ5r|V}
public void setCountType(String countTypes){ w[n|Sauy,
this.countType=countTypes; v$owG-_><
} rbqH9 S
public void setCountId(int countIds){ WB"$NYB
this.countId=countIds; g*AnrQ}P
} RT F9;]Ti
public String getCountType(){ Hvnak{5
return countType; tt6ElP|D
} {uDL"~^\
public int getCountId(){ oy;N3
return countId; P5%DvZB$w
} l)Q,*i
} k$7-F3
_+T;4U'p
CountCache.java q;}^Jpb;
-$.$6"]
/* 6Bo~7gnc
* CountCache.java =uYSZR
* f]0kG
* Created on 2007年1月1日, 下午5:01 .KIAeCvl\
* @|j`I1r.A
* To change this template, choose Tools | Options and locate the template under 9 %,_G.
* the Source Creation and Management node. Right-click the template and choose /e!/
* Open. You can then make changes to the template in the Source Editor. ;#G>q o
*/ Qo0okir
YL;ZZ2A
package com.tot.count; ~bWqoJ;Q
import java.util.*; +7|Oy3s
/** X6N^<Z$
* '_4u,
\SG
* @author 3Nsb@0
*/ /ZvNgaH5M
public class CountCache { tPDV"Md#m<
public static LinkedList list=new LinkedList(); @ J!)o d
/** Creates a new instance of CountCache */ H*A)U'`
public CountCache() {} Rqa#;wb!(
public static void add(CountBean cb){ A&Ut:OiA
if(cb!=null){ _ _-rP
list.add(cb); 23U9+
} &+J5GHt@
} 4_F<jx,G
} kVe^g]F
sFx$
CountControl.java b!PN6<SI
X`.4byqdK
/* >Djv8 0
* CountThread.java Ud*.[GRD~
* 4T Gg`$e;
* Created on 2007年1月1日, 下午4:57 "3Ag+>tuRW
* E IsA2 f
* To change this template, choose Tools | Options and locate the template under KG4~t=J`
* the Source Creation and Management node. Right-click the template and choose 1 mFc]1W
* Open. You can then make changes to the template in the Source Editor. $B2*
x$
*/ !MTm4Ls
^NHQ[4I
package com.tot.count; $QNfy.6Tn
import tot.db.DBUtils; 6!+xf
import java.sql.*; Jn'q'+
/** zbl h_6
* K%2,z3ps
* @author R)nhgp(~
*/ yXg783B|v
public class CountControl{ ]^8:"Ky'
private static long lastExecuteTime=0;//上次更新时间 WxWgY}`
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
{pd%I
/** Creates a new instance of CountThread */ fR_)e:
public CountControl() {} l.;y`cs
public synchronized void executeUpdate(){ (J\D"4q
Connection conn=null; TN7kt]a2
PreparedStatement ps=null; xZGR<+t
try{ o7DDL{iR/
conn = DBUtils.getConnection(); dK|MQ <
conn.setAutoCommit(false); NO`LSF
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 7M3q|7?
for(int i=0;i<CountCache.list.size();i++){ qAivsYN*
CountBean cb=(CountBean)CountCache.list.getFirst(); ;yBq'_e3
CountCache.list.removeFirst(); &EE6<-B-
ps.setInt(1, cb.getCountId()); 0=t_a]+
ps.executeUpdate();⑴ 5NJ@mm{0
//ps.addBatch();⑵ UF,T
} vkc(-n
//int [] counts = ps.executeBatch();⑶ q/m}+v]
conn.commit(); i*.Z~$
}catch(Exception e){ zw\"!=r^
e.printStackTrace(); \8ulX>]
} finally{ +\"@2mOH{+
try{ Wj8\~B=('
if(ps!=null) { }{=%j~V;&
ps.clearParameters(); x03G Jy5
ps.close(); @U}fvdft
ps=null; b.8HGt<%
} ~
Z%>N
}catch(SQLException e){} je_77G(F
DBUtils.closeConnection(conn); Fe"0Hp+
} 'G@Npp)&^
} }eEF/o
public long getLast(){ +:/`&LOS-
return lastExecuteTime; *M"lUw#(f
} G1$DVGo
public void run(){ &|/C*2A
long now = System.currentTimeMillis(); AGLzA+6M
if ((now - lastExecuteTime) > executeSep) { J\m7U
//System.out.print("lastExecuteTime:"+lastExecuteTime); dH#o11[
//System.out.print(" now:"+now+"\n"); s8.oS);`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); V9B $_j4
lastExecuteTime=now; sAnStS=>
executeUpdate(); tnRq?
} mfeyR
else{ Tg{d#U_qB
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :S~XE
} MbYa6jrF
} /vsQ <t;~
} Zt[
PkBi
//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 +SUQRDF@i
j%[|XfM
类写好了,下面是在JSP中如下调用。 0sV;TQt+f
+~w '?vNc
<% qI8{JcFx:
CountBean cb=new CountBean(); ApU5,R0
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o] )qv~o)
CountCache.add(cb); 0fi+tc30
out.print(CountCache.list.size()+"<br>"); sI9~TZ :
CountControl c=new CountControl(); %ze Sx
c.run(); pZjyzH{~
out.print(CountCache.list.size()+"<br>"); O?8G
%>