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: #-0}r
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CountBean.java S:*.,zC
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/* 1236W+
* CountData.java [+q':T1W-
* >AbgJ*X.
* Created on 2007年1月1日, 下午4:44 @Yv.HhO9
* g.&n
X/
* To change this template, choose Tools | Options and locate the template under %LH~Im=
* the Source Creation and Management node. Right-click the template and choose Spnshv8
* Open. You can then make changes to the template in the Source Editor. xcF:moL
*/ 3kAhvL
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package com.tot.count; /4]<ro67E6
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/** dK5|tWJX
* Q :<&<i=I
* @author vp"b_x1-
*/ wNHvYulI
public class CountBean { :U,n[.$5'
private String countType; )&Bf%1>
int countId; N,iYUM?
/** Creates a new instance of CountData */ jJ}3WJ
public CountBean() {} rW.o_z03^
public void setCountType(String countTypes){ :{(` ;fJ
this.countType=countTypes; X0h`g)Bbf
} th$?#4SbR
public void setCountId(int countIds){ (iwZs:k-
this.countId=countIds; baD`k?](
} O> 5xFz'm
public String getCountType(){ PD-<D~7
return countType; tSP)'N<
} n#{z"G
public int getCountId(){ 4\cJ}p}LZ{
return countId; ~HW}Wik
} f.Uvf^T}2
} xJQ-k/`
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CountCache.java O?6ph4'
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/* b6@(UneVM
* CountCache.java D4@'C4kL
* |>/T*zk<
* Created on 2007年1月1日, 下午5:01 #s 4v0auK
* p~n62(
* To change this template, choose Tools | Options and locate the template under (1t b
* the Source Creation and Management node. Right-click the template and choose w^_[(9
`
* Open. You can then make changes to the template in the Source Editor. b5-W K;
*/ -^Pn4y]A)
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package com.tot.count; %Sgdhgk1
import java.util.*; tX<.
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/** 2MV!@rx
* XLog+F$`
* @author %^5|3l3y
*/ sPu@t&$
public class CountCache { 7a,/DI2o
public static LinkedList list=new LinkedList(); _(qU%B
/** Creates a new instance of CountCache */ !|G 8b'
public CountCache() {} \Ax[/J2aO
public static void add(CountBean cb){ "kS(b4^
if(cb!=null){ ]r|nz~Aa$
list.add(cb); ODggGB` H`
} 0u3"$o'R
} 0q@U>#
} Z=L~W,0'
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CountControl.java QB/H
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/* ?hz9]I/8
* CountThread.java #@i1jZ
* #>]o' KQx
* Created on 2007年1月1日, 下午4:57 #QWG5
* k*?Axk#
* To change this template, choose Tools | Options and locate the template under ?`,Rkg0fe
* the Source Creation and Management node. Right-click the template and choose rZ|!y ~S|
* Open. You can then make changes to the template in the Source Editor. .4t-5,7s%
*/ ?qdZ]M4e
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package com.tot.count; 1 2Lc$\3P
import tot.db.DBUtils; -naj.omG|
import java.sql.*; Y[0
/** 7sC8|+
* W=[..d
* @author /C'dW
*/ e>OYJd0s
public class CountControl{ z_A:MoYfo
private static long lastExecuteTime=0;//上次更新时间 g9rsw7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Po~u-5
/** Creates a new instance of CountThread */ &!adW@y
public CountControl() {} ;;*'<\lP.j
public synchronized void executeUpdate(){ f|U
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Connection conn=null; /5PV|onO
PreparedStatement ps=null; ~O;'],#Co
try{ ^Hdru]A$2
conn = DBUtils.getConnection(); &fIx2ZM[
conn.setAutoCommit(false); Ah_Ttj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ",qcqG(
for(int i=0;i<CountCache.list.size();i++){ b8>2Y'X
CountBean cb=(CountBean)CountCache.list.getFirst(); na%DF@Rt#
CountCache.list.removeFirst(); !6yyX}%o
ps.setInt(1, cb.getCountId()); 'ot,6@~x>
ps.executeUpdate();⑴ ~ sC< V
//ps.addBatch();⑵ viLK\>>
} Q#,j,h
//int [] counts = ps.executeBatch();⑶ "#3p=}]
conn.commit(); Tej&1'G
}catch(Exception e){ 4!I;U>b b
e.printStackTrace(); F+lsza
} finally{ k~YZT 8
try{ pE^j Uxk6
if(ps!=null) { ZeL v!
ps.clearParameters(); _:ORu Vk
ps.close(); 5UTIGla
ps=null; o:.6{+|N
} 7[b]%i
}catch(SQLException e){} -UhSy>m
DBUtils.closeConnection(conn); KBb{Z;%
} %+1;iuDL
} _w'N
public long getLast(){ b6LwKUl
return lastExecuteTime; jOE~?{8m
} `X =2Ff
public void run(){ 5@:c6(5$
long now = System.currentTimeMillis(); bR0 z$~
if ((now - lastExecuteTime) > executeSep) { R3[H#*gF<
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,pg\5b
//System.out.print(" now:"+now+"\n"); jgkJF[t`
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); #Q6.r.3@x
lastExecuteTime=now; ]Zj6W9]m
executeUpdate(); r=`]L-}V
} #Fl5]> |
else{ iJr 1w&GL$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); GOzV#
} NY& |:F
} f:).wi
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} v4YY6?4
//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 kJOSGrg
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类写好了,下面是在JSP中如下调用。 ToNRY<!
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<% E>|xv#:~DV
CountBean cb=new CountBean(); }+" N
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ?11\@d
CountCache.add(cb); gO E3x^X*{
out.print(CountCache.list.size()+"<br>"); qXb{A*J
CountControl c=new CountControl(); HoFFce7o
c.run(); <]/z45?
out.print(CountCache.list.size()+"<br>"); 3 E~d
%>