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: #./fY;:cj
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CountBean.java %3s1z<;R[S
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/* 36.Z0Z1'F>
* CountData.java jY&k
* SbcS]H5Sk
* Created on 2007年1月1日, 下午4:44 f@6QvkIa
* c& <Fr[AK
* To change this template, choose Tools | Options and locate the template under 87=&^.~`
* the Source Creation and Management node. Right-click the template and choose }?lrU.@zg
* Open. You can then make changes to the template in the Source Editor. 1kz\IQ{
*/ %J#YM'g
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package com.tot.count; '-wj9OU
QZ!Y2Bz(4
/** f0!))/rSD
* \c,ap49RC
* @author Ii6<b6-
*/ G3txj
public class CountBean { ?}qttj
private String countType; K~uXO
int countId; Y&`=jDI
/** Creates a new instance of CountData */ ky8_UnaO
public CountBean() {} vjLJinJ/
public void setCountType(String countTypes){ '-QwssE
this.countType=countTypes; Ltv]pH}YN
} Cmu@4j&
public void setCountId(int countIds){ AW%50V
this.countId=countIds; PYiU_
} #akpXdXs
public String getCountType(){ "Hya6k>j
return countType; %) /s; Q,
} LI'6R=
public int getCountId(){ 5]~'_V
return countId; 3^IpE];+:u
} _> f`!PlB|
} !]42^?GH
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CountCache.java @X%C>iYa9
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/* Yf:IKY
* CountCache.java B#exHf8
* ,%6P0#-
* Created on 2007年1月1日, 下午5:01 &]g}u5J!=
* +j#+8Ze
* To change this template, choose Tools | Options and locate the template under oOnop-z7
* the Source Creation and Management node. Right-click the template and choose [I0:=yJ+
* Open. You can then make changes to the template in the Source Editor. t\?ik6
*/ iyA'#bE-
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package com.tot.count; "C}b%aO:
import java.util.*; 3("_Z%
/** \"qY "V
* eds o2
* @author H6kR)~zhf
*/ +Um( h-;
public class CountCache { "K ~
public static LinkedList list=new LinkedList(); T{Gj+7bQ~
/** Creates a new instance of CountCache */ 9l|@v=gw.
public CountCache() {} * ;-*x6
public static void add(CountBean cb){ %.vQU @2A
if(cb!=null){ LE&RY[
list.add(cb); uya.sF0]9B
} 46$._h
P
} 3%l*N&gsg:
} MPCBT!o4Z
}]e-{C}
CountControl.java VE#Wb7
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/* N|1M1EBOu>
* CountThread.java $()5VMb
* ,eOB(?Ku
* Created on 2007年1月1日, 下午4:57 `lQ3C{}
* %Da8{%{`Pc
* To change this template, choose Tools | Options and locate the template under j`oy`78O
* the Source Creation and Management node. Right-click the template and choose E;,u2[3
* Open. You can then make changes to the template in the Source Editor. \Npxv
*/ }
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package com.tot.count; R(('/J C
import tot.db.DBUtils; E'G4Y-
import java.sql.*; `2' #!-
/** >v:y?A,
* E7NV ^4h
* @author prYs
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*/ lH-/L(h2
public class CountControl{ Q7*SE%H
private static long lastExecuteTime=0;//上次更新时间 [OM7g'?S0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,ek_R)&[o
/** Creates a new instance of CountThread */ V`X2>-Ex
public CountControl() {} ?h.wK
public synchronized void executeUpdate(){ o4j[p3$
Connection conn=null; ?>hPO73{
PreparedStatement ps=null; bW$J~ ynM
try{ YwteZSbp6M
conn = DBUtils.getConnection(); fhar&\;S
conn.setAutoCommit(false); K!:azP,bZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aIJt0;
for(int i=0;i<CountCache.list.size();i++){ txW{7[w+,
CountBean cb=(CountBean)CountCache.list.getFirst(); w,w{/T+B
CountCache.list.removeFirst(); {kp"nl$<
ps.setInt(1, cb.getCountId()); ^c<ucv6.
ps.executeUpdate();⑴ 8JM&(Q%#
//ps.addBatch();⑵ F5?m6`g?
} M\sN@+
//int [] counts = ps.executeBatch();⑶ pNOwDJtK
conn.commit(); |rJ=Ksc
}catch(Exception e){ +g` 'J$
e.printStackTrace(); KB%"bqB|
} finally{ _jJPbKz
try{ }E0,z
if(ps!=null) { e}Cif2#d~
ps.clearParameters(); (5#nrF]
ps.close(); TatpXN\
ps=null; (&}i`}v_
} =4[v3Qx
}catch(SQLException e){} 4#ug]X4Y')
DBUtils.closeConnection(conn); <Fi%iA
} ERpnuMb
} CsTF
public long getLast(){ V=zi
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return lastExecuteTime; ,8:(OB|a
} cV 5CaaL
public void run(){ U'8bdsF_
long now = System.currentTimeMillis(); iMI lZ
if ((now - lastExecuteTime) > executeSep) { WOQP$D9
//System.out.print("lastExecuteTime:"+lastExecuteTime); q[HTnx
//System.out.print(" now:"+now+"\n"); }2(,K[?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); (IC]?n}
lastExecuteTime=now; yHs-h
executeUpdate(); o=21|z
} F{EnOr`,m=
else{ Q,p}:e
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); R($KSui
} gUxP>hB
} 4"{ooy^Q
} ?mWw@6G,
//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 u:[vaBh91
#>%X_o-o23
类写好了,下面是在JSP中如下调用。 v'VD0+3[H
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<% hJDi7P
CountBean cb=new CountBean(); q0$
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LM}Ib.
CountCache.add(cb); kBYNf =
out.print(CountCache.list.size()+"<br>"); aCQ?fq
CountControl c=new CountControl(); NXNY"r7~
c.run(); > `n,S
out.print(CountCache.list.size()+"<br>"); $4tWI O
%>