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: )gVz?-u+D
TGDrTyI?y
CountBean.java E[NszM[P
*q-VY[2
/* (l+0*o,(
* CountData.java dD351!-
* b9R0"w!ml
* Created on 2007年1月1日, 下午4:44 EQ [K
* j82x$I*
* To change this template, choose Tools | Options and locate the template under `a6AES'w$
* the Source Creation and Management node. Right-click the template and choose :P8X?C63W]
* Open. You can then make changes to the template in the Source Editor. l6T^e@*
*/ y0]"qB
\ gO!6
package com.tot.count; O>y*u 8
2`^M OGYk
/**
MFyi#nq
* V7<w9MM
* @author `T,^os#6
*/ .k -!/ ^
public class CountBean { VX:Kq<XwQ
private String countType; #;0F-pt
int countId; z!G?T(SpA
/** Creates a new instance of CountData */ l@:&0id4I
public CountBean() {} j4wsDtmAU
public void setCountType(String countTypes){ RF[Uy?es
this.countType=countTypes; s5\<D7
} sK@]|9ciQ
public void setCountId(int countIds){ dvcLZK
this.countId=countIds; 50e
vWD
} 3~%M4(
public String getCountType(){ :sX4hZK=G
return countType; 9
lXnNK
|]
} qTz5P
public int getCountId(){ SFjR SMi
return countId; 1\aV4T
} K BlJJH`z{
} /$d#9Uv
Y)68
CountCache.java )YVs=0j
ly`\TnC
/* R$x(3eyx
* CountCache.java (c
S'Nm5
* p`Ok(C_
* Created on 2007年1月1日, 下午5:01 r ?<?0j
* Mw`S.M. B
* To change this template, choose Tools | Options and locate the template under ]tNB^
* the Source Creation and Management node. Right-click the template and choose LfvNO/:,
* Open. You can then make changes to the template in the Source Editor. ,(B/R8ZF~
*/ emHaZhh
p
~pl|
package com.tot.count; "^)$MAZ
import java.util.*; /Yj; '\3
/** pS "A{k)i
* *SYuq)
* @author 4N)45@jk[
*/ F?Fxm*Wa/
public class CountCache { 5Mp$u756
public static LinkedList list=new LinkedList(); 06 an(&a9
/** Creates a new instance of CountCache */ z
s\N)LyM
public CountCache() {} FwV5{-(
public static void add(CountBean cb){ I@kMM12>c
if(cb!=null){ .[
s6x5M
list.add(cb); b y$S#ef
} &hEkm
} JSoInR1E
} ikb;,Js
p#N2K{E
CountControl.java ~
Ofn&[G
IN@ =UAc&
/* \;Sl5*kr
* CountThread.java w&Z.rB?
* fskc'%x
* Created on 2007年1月1日, 下午4:57 nj#kzD[n>
* )&[ol9+\
* To change this template, choose Tools | Options and locate the template under r.' cjUs
* the Source Creation and Management node. Right-click the template and choose o,qUf
* Open. You can then make changes to the template in the Source Editor. K8uqLSP '
*/ 6RfS_
MFz6y":~
package com.tot.count; Cy5M0{
import tot.db.DBUtils; *iUR1V Y
import java.sql.*; ?s]?2>p
/** ^3C%&
* $e%m=@ga
* @author RijFN.s
*/ {
3Qlx/6<
public class CountControl{ "d*-k R
private static long lastExecuteTime=0;//上次更新时间 brdY97s4
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 n],"!>=+
/** Creates a new instance of CountThread */ 7Q|v5@;pU
public CountControl() {} .X"\ Mg
public synchronized void executeUpdate(){ ^@$T>SB1
Connection conn=null; |H%,>r`9S
PreparedStatement ps=null; VO<P9g$UD
try{ ~Efi|A/
conn = DBUtils.getConnection(); C}71SlN'M
conn.setAutoCommit(false); EdCcnl?R6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); SpMHq_MLM
for(int i=0;i<CountCache.list.size();i++){ 36d6KS 7
CountBean cb=(CountBean)CountCache.list.getFirst(); ^=
'+#|:
CountCache.list.removeFirst(); $*7AG
ps.setInt(1, cb.getCountId()); 7G%^8
ce{!
ps.executeUpdate();⑴ v"sN
K
//ps.addBatch();⑵ Ku8qn\2"
} }q)dXFL=I#
//int [] counts = ps.executeBatch();⑶ DuRC1@e
conn.commit(); {;= {abj
}catch(Exception e){ 85{@&T
e.printStackTrace(); 5r^u7k
} finally{ 2SYV2
try{ Cp]q>lM"
if(ps!=null) { GC@U['
ps.clearParameters(); (X|lK.W y
ps.close(); npcL<$<6X
ps=null; `o%Ua0x2
} fn.}LeeS>
}catch(SQLException e){} t7/a5x
DBUtils.closeConnection(conn); ~t^'4"K*
} cKt8e^P
} 4K! @9+Mz
public long getLast(){ 5xc-MkIRL
return lastExecuteTime; `IK3e9QpcA
} eSSv8[u
public void run(){ 0*:4@go0}i
long now = System.currentTimeMillis(); b$}@0
if ((now - lastExecuteTime) > executeSep) { 6S?*z
`v
//System.out.print("lastExecuteTime:"+lastExecuteTime); (oB9$Zz!t
//System.out.print(" now:"+now+"\n"); mg
*kB:p
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #.<(/D+
lastExecuteTime=now; AeEF/*
executeUpdate(); Es+BV+x[.c
} 'Inqa;TQz
else{ 88+J(^y>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); HNV"'p;
} Cc` )P>L
} `BY&&Bv#?
} &uxwz@RC0
//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 Mh5 =]O+
%|3NCyJ*7
类写好了,下面是在JSP中如下调用。 z.*=3
Zc*gRC
<% {pEbi)CF,}
CountBean cb=new CountBean(); U=ie|
3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v,mn=Q&9
CountCache.add(cb); / Hexv#3
out.print(CountCache.list.size()+"<br>"); u )KtvC!
CountControl c=new CountControl(); /N`E4bKBR
c.run(); lISu[{b?
out.print(CountCache.list.size()+"<br>"); 3EX41)u
%>