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: 0R?LWm
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CountBean.java UazUr=|e
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/* Nf{tC9l
* CountData.java mt3j$r{_
* }&*,!ES*
* Created on 2007年1月1日, 下午4:44 yYZ0o.<&T*
* ?pF uV`Zm
* To change this template, choose Tools | Options and locate the template under }W R?n
* the Source Creation and Management node. Right-click the template and choose O>L
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* Open. You can then make changes to the template in the Source Editor. #]o#~:S=
*/ Jro%zZle
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package com.tot.count; RV+0C&0ff
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/** tJY3k$YX
* ?`D/#P
* @author Y]t)k9|vv
*/ V\o&{7!
public class CountBean { 0j|JyS:}G
private String countType; @460r
int countId;
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/** Creates a new instance of CountData */ W[tX%B
public CountBean() {} gkDlh{
public void setCountType(String countTypes){ _"%-=^_
this.countType=countTypes; `~3y[j]kO
} rwou[QU
public void setCountId(int countIds){ sv?Lk4_
this.countId=countIds; js\|xfDxP
} /F6=iHK(l
public String getCountType(){ wi/dR}*A
return countType; |d8x55dk
} :s OsG&y
public int getCountId(){ iPPW_Q9x
return countId; ({AqL#x`u
} )`.'QW
} qB IKJ
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CountCache.java uCNi&.
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/* (>\w8]
* CountCache.java ww"HV;i
* 7Z<ba^r}
* Created on 2007年1月1日, 下午5:01 6> Szxkz
* >A;9Ee"&
* To change this template, choose Tools | Options and locate the template under /?j
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* the Source Creation and Management node. Right-click the template and choose Lk|%2XGO&
* Open. You can then make changes to the template in the Source Editor. nE3'm[)
*/ S20L@e"U
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package com.tot.count; 5b2_{6t
import java.util.*; tk
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/** eO:wx.PW
* IZkQmA=
* @author ^/kn#1H7&
*/ z!GLug*j`
public class CountCache { U&\8~h
public static LinkedList list=new LinkedList(); #\]:lr{>?4
/** Creates a new instance of CountCache */ }XiV$[xHd
public CountCache() {} .UuCTH;6`
public static void add(CountBean cb){ u/BCl!`
if(cb!=null){ }vbs6u
list.add(cb); s"
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} o4"7i 9+g
} M1/Rba Q
} q-fxs8+m|
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CountControl.java !5P\5WF~Y
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/* 'bXm,Ed
* CountThread.java 1c}
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* A%pBvULH
* Created on 2007年1月1日, 下午4:57 #X(KW&;m
* D|}%(N@sl
* To change this template, choose Tools | Options and locate the template under Ol~jq;75
* the Source Creation and Management node. Right-click the template and choose jCMr[ G=
* Open. You can then make changes to the template in the Source Editor. AVys`{*c
*/ $i+
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package com.tot.count; }0P5~]S<5A
import tot.db.DBUtils; i<*{Z~B
import java.sql.*; xmEmdOoD
/** v/E_A3Ay&
* ;9r `P_r
* @author 2%'iTXF
*/ Xk_xTzJ
public class CountControl{ %!G]H
private static long lastExecuteTime=0;//上次更新时间 XJ|CC.]1u
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 jQp7TdvLE$
/** Creates a new instance of CountThread */ =~i~SG/f
public CountControl() {} EVW{!\8[
public synchronized void executeUpdate(){ JEK6Ms;)A
Connection conn=null; w}<CH3cx
PreparedStatement ps=null; ^f-?xXPx
try{ Q}N.DM@d3
conn = DBUtils.getConnection(); h98_6Dw(]
conn.setAutoCommit(false); =W6AUN/%p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RY(\/W#$
for(int i=0;i<CountCache.list.size();i++){ MHv2r
CountBean cb=(CountBean)CountCache.list.getFirst(); S'NZb!1+
CountCache.list.removeFirst(); \)=X=yn2
ps.setInt(1, cb.getCountId()); yk4Huq&2
ps.executeUpdate();⑴ q#$4Kt;
//ps.addBatch();⑵ 3:f<cy
} 3JiJ,<,7
//int [] counts = ps.executeBatch();⑶ ~@x@uY$5
conn.commit(); %8 )GuxG*
}catch(Exception e){ tTT./-*0
e.printStackTrace(); )pS1yYLj
} finally{ 4 |ryt4B
try{ =#AeOqs( q
if(ps!=null) { cvR|qHNX
ps.clearParameters(); P| o_/BS
ps.close(); Lzzf`jN]
ps=null; uM\(#jZ
} <|_/i/H
}catch(SQLException e){} L {6y]t7^
DBUtils.closeConnection(conn); z:hY{/-
} ZqHh$QBD
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} .D^=vuxt~
public long getLast(){ 7(m4,l+(
return lastExecuteTime; Vj7(6'Hg
} f -N:
public void run(){ 2t3'"8xJ
long now = System.currentTimeMillis(); AR i_m
if ((now - lastExecuteTime) > executeSep) { jlV~-}QKb7
//System.out.print("lastExecuteTime:"+lastExecuteTime); :"9 :J
//System.out.print(" now:"+now+"\n"); FqOV/B
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N#-P}\Q9
lastExecuteTime=now; m L#-U)?F
executeUpdate(); [-)N}rL>
} v,N*vqWS
else{ jg]_'^pVzr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X'4g\)*
} }yup`R
} ^zv0hGk 2
} - Dm/7Sxd`
//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 NPws^
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类写好了,下面是在JSP中如下调用。 o+sb2:x
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<% LXr
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CountBean cb=new CountBean(); _RT3Fk
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8=rD'*
CountCache.add(cb); gVM9*3LH6
out.print(CountCache.list.size()+"<br>"); q-%;~LF
CountControl c=new CountControl(); _&TA|Da
c.run(); 5?+ECxPt
out.print(CountCache.list.size()+"<br>"); kB-%T66\
%>