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: pyYm<dn
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CountBean.java m1H_kJ
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/* k#X~+}N^
* CountData.java o|O730"2F
* ~o_0RB
* Created on 2007年1月1日, 下午4:44 k=!lPIx
* lHQ:LI
* To change this template, choose Tools | Options and locate the template under nb
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* the Source Creation and Management node. Right-click the template and choose CC&o pC
* Open. You can then make changes to the template in the Source Editor. l*~O;do
*/ RQxL`7H
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package com.tot.count; '[(]62j
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/** zGgPW
* :0N}K}
* @author )N$T&
*/ 9/2VU<
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public class CountBean { &iKy
private String countType; =`Ii?xo
int countId; "i>?Tg^
/** Creates a new instance of CountData */ l@:Tw.+/9
public CountBean() {} E$l 4v>iA
public void setCountType(String countTypes){ #C^)W/dP
this.countType=countTypes; @A32|p}
} fk%W07x!
public void setCountId(int countIds){ 1OI/!!t1$
this.countId=countIds; .5$"qb
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} J]G]
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public String getCountType(){ TLu+5f
return countType; NzS(,F
} rSu+zS7`X
public int getCountId(){ M;2@<,rM
return countId; |)~t^
}
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} V'b$P2 ?^
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CountCache.java :Kq]b@X
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/* vq?Le j
* CountCache.java [}>!$::Y
* \dAs<${(
* Created on 2007年1月1日, 下午5:01 suOWmqLs
* [G!#y
* To change this template, choose Tools | Options and locate the template under lo!^h]iE !
* the Source Creation and Management node. Right-click the template and choose +G:CR,Z>+
* Open. You can then make changes to the template in the Source Editor. 6_mkt|E=
*/ i?{)o]i
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package com.tot.count; jxc^OsYj
import java.util.*; _:+hB9n s
/** p~Wy`g-
*
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* @author deLLqdZa
*/ w'uB&z4'
public class CountCache { 6W\G i>
public static LinkedList list=new LinkedList(); q4MR9ig1E_
/** Creates a new instance of CountCache */ {,NF'x4$
public CountCache() {} [?>\]
public static void add(CountBean cb){ &&PXWR!%]
if(cb!=null){ lcVZ 32MQ
list.add(cb); uH{oJSrK
} .9NYa |+0
} n2A
;
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} k\76`!B
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CountControl.java UaCfXTG
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/*
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* CountThread.java S(^HIJK
* 0SjB&J
* Created on 2007年1月1日, 下午4:57 y5{Vx{V"Q
* \>$3'i=mQ
* To change this template, choose Tools | Options and locate the template under 9Bao~(j/k
* the Source Creation and Management node. Right-click the template and choose *fCmZ$U:{
* Open. You can then make changes to the template in the Source Editor. c/DK31K
*/ 3\}>nE
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package com.tot.count; xyD2<?dGUb
import tot.db.DBUtils; h6b(FTC^
import java.sql.*; 9Iu"DOxX%
/** B#DnU;=O#+
* OKPNsN
* @author "&:H }Jd
*/ {E[t(Ig
public class CountControl{ r2*8.j51
private static long lastExecuteTime=0;//上次更新时间 )+Y"4?z~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =PF2p'.o
/** Creates a new instance of CountThread */ D7r&z?
public CountControl() {} s0O]vDTR,H
public synchronized void executeUpdate(){ [ $5u:*
Connection conn=null; 9Nw&l@
PreparedStatement ps=null; n$ rgJ
try{ Xub*i^(]
conn = DBUtils.getConnection(); b:5-0uxjs
conn.setAutoCommit(false); jM}(?^@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n)0M1o#
for(int i=0;i<CountCache.list.size();i++){ '%X29B5
CountBean cb=(CountBean)CountCache.list.getFirst(); .?vHoNvo
CountCache.list.removeFirst(); &,P; 7 R
ps.setInt(1, cb.getCountId()); Q=61.lP6
ps.executeUpdate();⑴ ;f~fGsH}e'
//ps.addBatch();⑵ fG d1
} ypgM&"eR
//int [] counts = ps.executeBatch();⑶ d_,Ql708f
conn.commit(); ]$uC~b
}catch(Exception e){ q9wObOS$
e.printStackTrace(); bg!(B<!X
} finally{ DcNp-X40I
try{ 0l3[?YtXc
if(ps!=null) { le'
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ps.clearParameters(); 1eywnOjrj
ps.close(); Y7zs)W8xTT
ps=null; $%^](-
} gnGh )
}catch(SQLException e){} !?>QN'p.b
DBUtils.closeConnection(conn); Wco2i m
} *MS$C$HOq
} r .'xqzF/
public long getLast(){ @ x .`z
return lastExecuteTime; ;Xf1BG r
} c`/VYgcTqB
public void run(){ soLW'8
long now = System.currentTimeMillis(); q9dplEe5
if ((now - lastExecuteTime) > executeSep) { {i+
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//System.out.print("lastExecuteTime:"+lastExecuteTime); s=]NKJaQH
//System.out.print(" now:"+now+"\n"); b*Q3j}c Z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); $/lM %yXe
lastExecuteTime=now; D;s%cL`
executeUpdate(); `#'j3,\6
} wAw1K 2d
else{ .'&pw}F
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); c:e3hJ
} PZQAlO,
} ^.R!sQ
} |gWA'O0S
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 -b
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类写好了,下面是在JSP中如下调用。 +SF+$^T
ilde<!?
<% UOFb.FRP>
CountBean cb=new CountBean(); Xy%||\P{)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 4BUG\~eI3
CountCache.add(cb); "AZ|u#0P
out.print(CountCache.list.size()+"<br>"); !qp$Xtf+
CountControl c=new CountControl(); xVw@pR;
c.run(); ]\KVA)\
out.print(CountCache.list.size()+"<br>"); ^8EW/$k
%>