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: EMJ}tvL0Tp
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CountBean.java mAXTO7
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/* V
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* CountData.java Ik~5j(^E-
* J2yq|n?2gq
* Created on 2007年1月1日, 下午4:44 Cvi-4
* @-Gf+*GZys
* To change this template, choose Tools | Options and locate the template under ~>)cY{wE_
* the Source Creation and Management node. Right-click the template and choose '0?5K0
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* Open. You can then make changes to the template in the Source Editor. g"<kj"
*/ \#~~,k
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package com.tot.count; o$2fML
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/** n j1 cqh
* mnG\UK,k
* @author RkC?(p
*/ .bew,92
public class CountBean { &XN*T.Y`
private String countType; T*LbZ"A
int countId; 5E~][. d
/** Creates a new instance of CountData */ ./.E=,j
public CountBean() {} wxvt:==
public void setCountType(String countTypes){ T,jxIFrF
this.countType=countTypes; ,ad~6.Z_)
} 0wxQ,PI1'
public void setCountId(int countIds){ "<bL-k*H)
this.countId=countIds; IHf
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} -3haLdRk6
public String getCountType(){ 0]NjsOU=
return countType; A9F&XF7{
} &>sG xK
public int getCountId(){ 5wr0+Xo
return countId; sp'q=^t
} `[Kh[|
} cLJ|VD7
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CountCache.java W@/D2K(
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/* #& Rx(
* CountCache.java m_U__CZ}Tt
* g'hBs
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* Created on 2007年1月1日, 下午5:01 -%"MAIJnX
* )HR'FlxOd
* To change this template, choose Tools | Options and locate the template under t+p-,ey^@
* the Source Creation and Management node. Right-click the template and choose ,Laz515
* Open. You can then make changes to the template in the Source Editor. $##LSTA
*/ uV\~2#o$_
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package com.tot.count; v0,&wdi
import java.util.*; DP=\FG"}x
/** &C.m*^`^
* e<-^
* @author R~d{Yv
*/ -A)/CFIZ
public class CountCache { "<1-9CMl
public static LinkedList list=new LinkedList(); QI{<q<
/** Creates a new instance of CountCache */ @2R+?2 j
public CountCache() {} apd"p{
public static void add(CountBean cb){ 5gH'CzU?
if(cb!=null){ (qg~l@rf
list.add(cb); u%rB]a$/
} S<nbNSu6+
} ah|`),o(k
} X:d[eAu0
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CountControl.java Ops""#Zi
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/* &T[BS;
* CountThread.java $Y<(~E$FX
* T(iL#2^
* Created on 2007年1月1日, 下午4:57 axLO: Q,
* (5&l<u"K~
* To change this template, choose Tools | Options and locate the template under O*-sSf
* the Source Creation and Management node. Right-click the template and choose *[0)]|r
* Open. You can then make changes to the template in the Source Editor. ]]lM)
*/ F >co#
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package com.tot.count; ~R\U1XXyUY
import tot.db.DBUtils; vp..>BMJ
import java.sql.*; Wkc^?0p
/** VO+3@d:
* ["XS|"DM
* @author 8,YxCm ie
*/ 0/0rWqg
/
public class CountControl{ 4Vrx9 sA1
private static long lastExecuteTime=0;//上次更新时间 kH>^3(Q\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +d/^0^(D\5
/** Creates a new instance of CountThread */ \X0wr%I
public CountControl() {} b%M|R%)]
public synchronized void executeUpdate(){ [Se0+\,&
Connection conn=null; 8!VFb+
PreparedStatement ps=null; "i/3m'<2
try{ ~ZXAW~a}
conn = DBUtils.getConnection(); "RM vWuNt
conn.setAutoCommit(false); IX
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ljRR{HOl
for(int i=0;i<CountCache.list.size();i++){ 5"8R|NU:\0
CountBean cb=(CountBean)CountCache.list.getFirst(); :h)A/k_
CountCache.list.removeFirst(); @AAkEWo)_
ps.setInt(1, cb.getCountId()); Mq2[^l!qu
ps.executeUpdate();⑴ Trwk9 +
//ps.addBatch();⑵ MtIhpTX
} 8et.A
//int [] counts = ps.executeBatch();⑶ TLiA>`r=
conn.commit(); 9G=ZB^
}catch(Exception e){ ky98Bz%
e.printStackTrace(); {;j@-=pV
} finally{ sKuPV
try{ ht@s!5\LK
if(ps!=null) { HRZ3}8Qj
ps.clearParameters(); "J (.dg]"
ps.close(); 0A>Fl*
ps=null; xtP=/B/
} =*?2+ ;
}catch(SQLException e){} k7ODQ(*v
DBUtils.closeConnection(conn); =D6H?K-k!
} C>*]a(5k
} @C fxPA
public long getLast(){ l\Or.I7n
return lastExecuteTime; t?R=a- ZI
} "7tEk<x
public void run(){
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long now = System.currentTimeMillis(); FI|@=l;_
if ((now - lastExecuteTime) > executeSep) { k1
//System.out.print("lastExecuteTime:"+lastExecuteTime); Uv"GG:
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//System.out.print(" now:"+now+"\n"); xr\wOQ*`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `nDgwp:b"
lastExecuteTime=now; ]kd )j
executeUpdate(); #Zy-X_r
} DG
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else{ d^<a)>5h
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ,Cckp! 6
} wf8GH}2A
} -O=a"G=
} (iZE}qf7g
//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 X@ Gm:6
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类写好了,下面是在JSP中如下调用。 uY;2tZldf=
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<% Z 7M%}V%
CountBean cb=new CountBean(); bUp
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (gl/NH!
CountCache.add(cb); = ?hx+-'
out.print(CountCache.list.size()+"<br>"); (]mh}=:KDg
CountControl c=new CountControl(); *0,?QS-a
c.run(); =Xc[EUi<;g
out.print(CountCache.list.size()+"<br>"); U-#t&yjh#
%>