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: ;,&cWz
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CountBean.java FH~:&;
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/* dJ"M#X!Zu
* CountData.java '#'noB;,
* 4VJUu`[
* Created on 2007年1月1日, 下午4:44 o!M8V ^vW
* 4Z)s8sD KW
* To change this template, choose Tools | Options and locate the template under ~bLx2=-"
* the Source Creation and Management node. Right-click the template and choose p%Z:SZZ
* Open. You can then make changes to the template in the Source Editor. +=3=% %?C
*/ 6X \g7bg
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package com.tot.count; tk"+ u_u w
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/** Fv$tl)p*
* gQn%RPMh
* @author :$WO"HfMSn
*/ yKc-:IBb{u
public class CountBean { u R0UfKK
private String countType; b[74$W{
int countId; {X!OK3e
/** Creates a new instance of CountData */ /WuYg
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public CountBean() {} xlI=)ak{
public void setCountType(String countTypes){ PF%-fbh!~
this.countType=countTypes; Ir9GgB
} [4z,hob
public void setCountId(int countIds){ p#@ #$u-
this.countId=countIds; V@
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} Cr.YSWg)4
public String getCountType(){ 0,%{r.\S
return countType; z#*.9/y\^R
} .xRdKt!p
public int getCountId(){ QQ(}71U
return countId; L+am-k:T~
} * ,hhX
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} cLtVj2Wb
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CountCache.java 39X~<\&'
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/* 4b;Mb
* CountCache.java =oBpS=<7
* WXQ@kQD
* Created on 2007年1月1日, 下午5:01 7~7L5PRW
* QN:v4,$d
* To change this template, choose Tools | Options and locate the template under 5J5?cs-!
* the Source Creation and Management node. Right-click the template and choose ]~TsmR[
* Open. You can then make changes to the template in the Source Editor. XNz+a|cF
*/ #Bd]M#J17a
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package com.tot.count; 6D;N.wDZ
import java.util.*; 6nx\|F
/** zHJCXTM
* ={BD*=i
* @author j q+(2
*/ "=h1gql'
public class CountCache { xcB\Y:
public static LinkedList list=new LinkedList(); 4#$#x=:
/** Creates a new instance of CountCache */ hG1:E:}
public CountCache() {} 86ao{l6l C
public static void add(CountBean cb){ a|ufm^F
if(cb!=null){ 4E$MhP
list.add(cb); 98[uRywI
} B~Sj#(WEa
} .~]|gg~
} y'R}
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CountControl.java <:S qMf
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/* }%wd1`l7
* CountThread.java ?cV,lak
* NoI|Dz
* Created on 2007年1月1日, 下午4:57 o4Q?K.9c
* {2\Y%Y'}*
* To change this template, choose Tools | Options and locate the template under TGCB=e
* the Source Creation and Management node. Right-click the template and choose S$mv(C
* Open. You can then make changes to the template in the Source Editor. !=[Y yh
*/ q}{E![ZTu
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package com.tot.count; 8D*7{Q
import tot.db.DBUtils; 1.3#PdMR,
import java.sql.*; [M|^e;tWK
/** =*\s`ox`
* n
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* @author ?@64gdlwq
*/ =2R4Z8G
public class CountControl{ \6b~$\~B
private static long lastExecuteTime=0;//上次更新时间 u$nzpw0=H
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 k&Pt\- 9on
/** Creates a new instance of CountThread */ &YhAB\Rw
public CountControl() {} w~3X
m{
public synchronized void executeUpdate(){ p Cz6[*kC
Connection conn=null; ]J7qsMw
PreparedStatement ps=null; pBsb>wvej
try{ dY1t3@E
conn = DBUtils.getConnection(); i5e10@Q{
conn.setAutoCommit(false); o E+'@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 'Y?-."eKh
for(int i=0;i<CountCache.list.size();i++){ X=)V<2WO
CountBean cb=(CountBean)CountCache.list.getFirst(); bLc5$U$!I
CountCache.list.removeFirst(); -U|c~Cqc
ps.setInt(1, cb.getCountId()); -]N2V'QB
ps.executeUpdate();⑴ I Xc `Ec
//ps.addBatch();⑵ 0z8(9DlTc
} MB]E[&Q!
//int [] counts = ps.executeBatch();⑶ AWO)]rM
conn.commit(); [txOh!sxD
}catch(Exception e){ #CS>_qe.{
e.printStackTrace(); E_,/)U8
} finally{ *^?tr?e%I<
try{ xT*'p&ap
if(ps!=null) { O
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ps.clearParameters(); hx$]fvDevD
ps.close(); {cK<iQJ
ps=null; u0C:q`;z
} EC+t-:a]
}catch(SQLException e){} CK_dEh2c
DBUtils.closeConnection(conn); i<uU_g'M
} q;{(o2g
} )_#V>cvNG
public long getLast(){ {##G.n\~
return lastExecuteTime; 9b.
kso9.
} c`O~I<(Pm
public void run(){ {oQs*`=l>
long now = System.currentTimeMillis(); g )hEzL0k
if ((now - lastExecuteTime) > executeSep) { v\xl?F
//System.out.print("lastExecuteTime:"+lastExecuteTime); $>rt0LOF
//System.out.print(" now:"+now+"\n"); 3.&BhLT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Iiy5;:CX:q
lastExecuteTime=now; Jqoo&T")
executeUpdate(); Yh<F-WOo2
} )nm+_U
else{ 4n,&,R r#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); h&"9v~
} V)$!WPL@
} C5 ~#lNC
} t{k:H4
//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 !I7$e&Uz@
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类写好了,下面是在JSP中如下调用。 iI GK"}
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<% F^dJ{<yX
CountBean cb=new CountBean(); 2BccE
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .f~9IAXP`
CountCache.add(cb); =*UK!y?n
out.print(CountCache.list.size()+"<br>"); @Q1!xA^S
CountControl c=new CountControl(); bT:u|/I
c.run(); >8Oa(9 n
out.print(CountCache.list.size()+"<br>"); S_lGrk\j
%>