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: t!*+8Q!e
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CountBean.java 7K)6^r^
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/* g?-lk5
* CountData.java |f~@8|MQP+
* .CL^BiD.D
* Created on 2007年1月1日, 下午4:44 ee%fqVQ8P
* ~gB>) ]
* To change this template, choose Tools | Options and locate the template under 5N%93{L
* the Source Creation and Management node. Right-click the template and choose ,'[<bP'%_
* Open. You can then make changes to the template in the Source Editor. 9Gv[8'I
*/ xX*H7#
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package com.tot.count; !vG'J\*xc
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/** 'cY` w
* j'9"cE5_
* @author i4^o59}8
*/ #fT*]NN
public class CountBean { XsnF~)YW
private String countType; LPMU8Er
int countId; J[f;Xlh
/** Creates a new instance of CountData */ (`y*V;o4
public CountBean() {} x| yEtO&
public void setCountType(String countTypes){ . e=C{
this.countType=countTypes; A.hd
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} Yjx|9_|Xn
public void setCountId(int countIds){ v) vkn/:
this.countId=countIds; h/~n\0,J/
} pdE3r$C
public String getCountType(){ ?LvCR_D:
return countType; zZVfj:i8
} xg)v0y~
public int getCountId(){ E<yW\
return countId; p.LFVFPT
} v\p;SwI
} ]`Oo%$Ue
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CountCache.java #1>X58I^
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/* jBegh9KHq
* CountCache.java >JiltF7H0
* sQMFpIrr
* Created on 2007年1月1日, 下午5:01 **}h&k&%2
* ,3@#F/c3i~
* To change this template, choose Tools | Options and locate the template under In`mtn q
* the Source Creation and Management node. Right-click the template and choose FJ asS8
* Open. You can then make changes to the template in the Source Editor. *Z|y'<s
*/ Ei2'[PK
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package com.tot.count; OKoan$#sn
import java.util.*; YW{C} NA
/** dd]/.Z
* lsJnI|
* @author _q~=~nub
*/ ANgw"&&>(
public class CountCache { 9W(dmde>
public static LinkedList list=new LinkedList(); 1Tu
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/** Creates a new instance of CountCache */ .'Vww
public CountCache() {}
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public static void add(CountBean cb){ s8}@=]aA
if(cb!=null){ \hB5@e4i2
list.add(cb); uDEvzk42
} hZ.Z3`v70
} Q[nEsYP
} mauI42
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CountControl.java fMOU$0]$<
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/* 9(@\&>)
* CountThread.java fl\ly`_
* #-bA[eQV
* Created on 2007年1月1日, 下午4:57 ]Ux<aiY]a
* ~Q\3pI. |
* To change this template, choose Tools | Options and locate the template under 7D<#(CE{
* the Source Creation and Management node. Right-click the template and choose ]MxC_V+P`
* Open. You can then make changes to the template in the Source Editor. {7)st
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*/ ub|V\M{
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package com.tot.count; aoXb2 2]{
import tot.db.DBUtils; B'fb^n<
import java.sql.*; ;Rv!k&Df
/** 5O\*h;U 6
* 3g >B"t
* @author ;aw=MV
*/ _'(,
public class CountControl{ uuQ(&
private static long lastExecuteTime=0;//上次更新时间 Rj4|Q:XG
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 cJrmm2.0kD
/** Creates a new instance of CountThread */ -4cXRv]
public CountControl() {} >(;{C<6|^
public synchronized void executeUpdate(){ rwI
Connection conn=null; 5F~'gLH/F-
PreparedStatement ps=null; ~-I+9F
try{ %HL*c=
conn = DBUtils.getConnection(); 7k rUKYVo
conn.setAutoCommit(false); _]Zs,Hy
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); `DC2gJKk%
for(int i=0;i<CountCache.list.size();i++){ l g-X:Z.
CountBean cb=(CountBean)CountCache.list.getFirst(); ndkti5L,
CountCache.list.removeFirst(); ( vca&wI!
ps.setInt(1, cb.getCountId()); 9T1ZL5
ps.executeUpdate();⑴ u,UmrR
//ps.addBatch();⑵ hC\6-
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} 49vcoHlf
//int [] counts = ps.executeBatch();⑶ Qc pm!
conn.commit(); R;j!}D!4
}catch(Exception e){ :AE&Ny4
e.printStackTrace(); <>8WQn,K
} finally{ c`o7d)_Ke
try{ }b-g*dn]5
if(ps!=null) { ~x|F)~:0=
ps.clearParameters(); uH(f$A
ps.close(); s{$(*_
ps=null; N|6MP
e
} w/kt3Lw
}catch(SQLException e){} I= &stsH
DBUtils.closeConnection(conn); 6*3.SGUY
} RS^lKJ1 U
} L>3x9
public long getLast(){ eN^qG
42
return lastExecuteTime; 43@{JK9G
} /\hzb/
public void run(){ (Kv#m
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long now = System.currentTimeMillis(); m8o(J\]
if ((now - lastExecuteTime) > executeSep) { ]]*7\ :cb
//System.out.print("lastExecuteTime:"+lastExecuteTime); D/Mi^5H)
//System.out.print(" now:"+now+"\n"); sPR1?:0:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); lk( }-
lastExecuteTime=now; v~^{{O
executeUpdate(); $GTU$4u
} fe9LEM8j
else{ [Ki0b^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -&-Ma,M?
} +>r/ 0b
} o/+13C
} SF>c\eTtx
//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 c5u@pvSP
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类写好了,下面是在JSP中如下调用。 ekWePL;rR2
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<%
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CountBean cb=new CountBean(); ~W{2Jd
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *exS6@N]
CountCache.add(cb); e8GEoD
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); L{8xlx`
c.run(); E6pMT^{K
out.print(CountCache.list.size()+"<br>"); 9T*v9d
%>