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: ;m>/tD%
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CountBean.java H?M:<q0|G
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/* HC1<zW[
* CountData.java nCp_RJu
* O6 s3#iu
* Created on 2007年1月1日, 下午4:44 <|?)^;R5!
* ]W4{|%@H"
* To change this template, choose Tools | Options and locate the template under _x3=i\O,
* the Source Creation and Management node. Right-click the template and choose ^);M}~
* Open. You can then make changes to the template in the Source Editor. %n8CK->
*/ 6OAEAIh
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package com.tot.count; aPK:k$.
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/** frDMFEXXP
* <y~Ba@1u
* @author :).NA
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*/ h(~/JW[
public class CountBean { )"hd"
private String countType; -y|']I^ &
int countId; jAue+tB
/** Creates a new instance of CountData */ )!cucY
public CountBean() {} x3#:C=
public void setCountType(String countTypes){ p~=z)7%e'
this.countType=countTypes; >3B{sn}
} 7CSz
public void setCountId(int countIds){ :@"o.8p
this.countId=countIds; Hm!"%
} ;~djbo0,X
public String getCountType(){ Uf]$I`T#
return countType; nTD%i~t~o
} 2p#d
public int getCountId(){ &z5?]`ALu
return countId; 1%R${Qhr
} ebNRZJ?C,
} m[Ihte->
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CountCache.java MN5}}@
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/* mAGD qz>f
* CountCache.java lo'#dpt<
* Mp!1xx
* Created on 2007年1月1日, 下午5:01 aXQAm$/
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* '0)`.
* To change this template, choose Tools | Options and locate the template under 3)LS#=
* the Source Creation and Management node. Right-click the template and choose a9.255
* Open. You can then make changes to the template in the Source Editor. XOQ0(e6
*/ ;<''oY
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package com.tot.count; 5S!j$_(
import java.util.*; 7-n HPDp'
/** V9}\0joM
* eq8faC5
* @author e!L5v?
*/ #3LZX!
public class CountCache { +l/kH9m
public static LinkedList list=new LinkedList(); LVm']_K(f
/** Creates a new instance of CountCache */ 9xq3>(
public CountCache() {} {jQLr7'
public static void add(CountBean cb){ 5lP8#O?=
if(cb!=null){ IDw`k[k
list.add(cb); z"\w9 @W
} ^c(r4#}$"
} Qbjm,>H/^
} 1y6<gptx
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CountControl.java )4s7,R
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/* @&&}J
* CountThread.java iHf):J?8
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* zjcSn7iu
* Created on 2007年1月1日, 下午4:57 f{O-\
* KehM.c^
* To change this template, choose Tools | Options and locate the template under zDtC]y'
* the Source Creation and Management node. Right-click the template and choose >R6mI
* Open. You can then make changes to the template in the Source Editor. zA+0jhuG
*/ gg^iYTpt
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package com.tot.count; /ar0K9`c
import tot.db.DBUtils; C@t,oDU#
import java.sql.*; xr@;w8X`^
/** V_m!<sr (
* 60nP'xfR
* @author Opg_-Bf
*/ iHc(e(CB<
public class CountControl{ x\~ <8o
private static long lastExecuteTime=0;//上次更新时间 QJVB:>A
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .=<s@Sg,t
/** Creates a new instance of CountThread */ 4:Ju|g]O
public CountControl() {} :k`Qj(7S
public synchronized void executeUpdate(){ \ >wQyz
Connection conn=null; \nWbGS(
PreparedStatement ps=null; 7BwR ].
try{ OgQ8yKfDB
conn = DBUtils.getConnection(); i%<NKE;v7m
conn.setAutoCommit(false); 0QPY+6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ DCLu^:|C"
CountBean cb=(CountBean)CountCache.list.getFirst(); 2vG
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CountCache.list.removeFirst(); fibudkg'>
ps.setInt(1, cb.getCountId()); ^q/$a2<4
ps.executeUpdate();⑴ X 5}=|%Y
//ps.addBatch();⑵ uqI'e_&=&5
} 6bjZW ~
//int [] counts = ps.executeBatch();⑶ <&+jl($"
conn.commit(); -~xQ@ +./
}catch(Exception e){ ia;osqW
e.printStackTrace(); L >"O[@
} finally{ m{Uh{G$
try{ :BV $3]y
if(ps!=null) {
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ps.clearParameters(); ZnAQO3%y
ps.close(); d/Wp>A@dob
ps=null; W-|CK&1
} <P0 P*>M
}catch(SQLException e){} eg?p)|
DBUtils.closeConnection(conn); fr04nl
} ;vPFRiFK
} [4YRyx&:++
public long getLast(){ No[9m_
return lastExecuteTime; q&&"8.w-
} U&Atgv
public void run(){ U=j`RQ 9,
long now = System.currentTimeMillis(); "+qZv(
if ((now - lastExecuteTime) > executeSep) { >FHx],
//System.out.print("lastExecuteTime:"+lastExecuteTime); ZlE=P4`X:
//System.out.print(" now:"+now+"\n"); :8}Qt^p
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Tmu2G/yi
lastExecuteTime=now; G,P
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executeUpdate(); *\}$,/m['
} 6|n3Q$p
else{ k'&1,78[l
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); mC\<fo-u
} ?6ssSjR}
} ;w]1H&mc*A
} 9eP*N(m<
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 EXH,+3fQp
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类写好了,下面是在JSP中如下调用。 >$CNR*}@
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<% {6Nbar@3
CountBean cb=new CountBean(); L7GNcV]c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); /u90)x
CountCache.add(cb); (vi^ t{k
out.print(CountCache.list.size()+"<br>"); y,1U]1TP
CountControl c=new CountControl(); ,|?#+O{
c.run(); x5smJ__/
out.print(CountCache.list.size()+"<br>"); lB/^
%>