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'_
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CountBean.java eP~bl
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/* ]($ \7+
* CountData.java !ooi.Oz*Tu
* WZa6*pF
* Created on 2007年1月1日, 下午4:44 -TD\?Q
* }L0
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* To change this template, choose Tools | Options and locate the template under (bm^R-SbB
* the Source Creation and Management node. Right-click the template and choose MqJTRBs%
* Open. You can then make changes to the template in the Source Editor. Zo UeLU
*/ # epP~J_f
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package com.tot.count; @Y0ZW't
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/** \?
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* Whd >
* @author @9^OHRZX
*/ w4fKh
public class CountBean { j"Jf|Hq $
private String countType; !7t&d
int countId; bQD8#Ml1
/** Creates a new instance of CountData */ [G 9Pb)
public CountBean() {} =r]l"T
public void setCountType(String countTypes){ Xg~9<BGsi
this.countType=countTypes; stiF`l
} RvG=GJJ9
public void setCountId(int countIds){ )\])?q61
this.countId=countIds; j_C"O,WS
} Nu qmp7C
public String getCountType(){ ?}`-?JB1
return countType; c0wLc,)G
} !'_7MM
public int getCountId(){ ~\=D@G,9
return countId; 7U7!'xU
} izSX
} ~vTwuc\(H
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CountCache.java #91^1jyMf
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/* U\%r33L )
* CountCache.java k A=5Kc
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* Created on 2007年1月1日, 下午5:01
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* yjT>bu]
* To change this template, choose Tools | Options and locate the template under DN:|
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* the Source Creation and Management node. Right-click the template and choose {Q>OZm\+
* Open. You can then make changes to the template in the Source Editor. A=kOSq 4Q
*/ Cab-:2L]
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package com.tot.count; 4?Y7.:x
import java.util.*; aEdA'>
/** WIU]>_$.
* !<TkX/O
* @author zgY VB}
*/ x[mz`0
public class CountCache { xVB
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public static LinkedList list=new LinkedList(); "U^m~N9k{
/** Creates a new instance of CountCache */ #E+ybwA
public CountCache() {} 0n:cmML)D
public static void add(CountBean cb){ k, N{
if(cb!=null){ F]M-r{
list.add(cb); "R5G^-<hp
} YM`T"`f
} S ,F[74K
} ?OW!D?
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CountControl.java \me5"ZU
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/* )l9KDObis
* CountThread.java ECt<\h7}
* OPN\{<`*d
* Created on 2007年1月1日, 下午4:57 e-*@R#x8+
* r 10VFaly
* To change this template, choose Tools | Options and locate the template under 5Pf=Uj6D
* the Source Creation and Management node. Right-click the template and choose n*"r!&Dg
* Open. You can then make changes to the template in the Source Editor. 1\}XL=BE
*/ Z,"4f*2
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package com.tot.count; U
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import tot.db.DBUtils; (Yz[SK=U}
import java.sql.*; a0hBF4+6
/** Sm<*TH!\n_
* ~AjPa}@ f
* @author NWh1u`
*/ frUs'j/bZ
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 x^@oY5}cr
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 N!c FUZ5]
/** Creates a new instance of CountThread */ e".=E;o`
public CountControl() {} S3M!"l
public synchronized void executeUpdate(){ $B8Vg `+
Connection conn=null; ^?RH<z
PreparedStatement ps=null; ~ 1;M4K
try{ p-IJ':W
conn = DBUtils.getConnection(); .1TuHC\mC
conn.setAutoCommit(false); W`PJflr|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); YyYZD{^
for(int i=0;i<CountCache.list.size();i++){ ~*bfS}F8I
CountBean cb=(CountBean)CountCache.list.getFirst(); /[dMw
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CountCache.list.removeFirst(); p _[,P7
ps.setInt(1, cb.getCountId()); FzEs1hpl
ps.executeUpdate();⑴ W8 Ssv
//ps.addBatch();⑵ ^vMlRt;
} M6&=-
//int [] counts = ps.executeBatch();⑶ <y8oYe_!
conn.commit(); Tr_gc~
}catch(Exception e){ $F^VtCx2&
e.printStackTrace(); F%<*a,m6g
} finally{ f2[R2sto@
try{ q{`1[R
if(ps!=null) { Uj;JN}k
ps.clearParameters(); ="78#Wfj2
ps.close(); MO$yst?fK
ps=null; W:8MqVm34
} Eu' ;f_s
}catch(SQLException e){} ]7}!3 m
DBUtils.closeConnection(conn);
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} n
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} 9;Z{++z
public long getLast(){ 1q(Qr
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return lastExecuteTime; K@*+;6y@
} I'*,<BPG
public void run(){ @Dfg6<0
long now = System.currentTimeMillis(); rX)&U4#[m
if ((now - lastExecuteTime) > executeSep) { .O"a: ^i
//System.out.print("lastExecuteTime:"+lastExecuteTime); W+;=8S
//System.out.print(" now:"+now+"\n"); (=uT*Cb
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C*ep8{B
lastExecuteTime=now; ewd
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executeUpdate();
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} QTBc_Z
else{ VOD-<
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Awa| (]
} [ne51F5_
} }0pp"[JU
} /%g9g_rt#
//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 \_O#M
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类写好了,下面是在JSP中如下调用。 hy~[7:/<I&
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<% _U&HXQ8X
CountBean cb=new CountBean(); UB5H8&Rf!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Q k}RcP
CountCache.add(cb); 27fLW&b2
out.print(CountCache.list.size()+"<br>"); =V|jd'iwx
CountControl c=new CountControl(); <&Xl b0
c.run(); jUM'f24
out.print(CountCache.list.size()+"<br>"); l,hOnpm9
%>