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: [BdRx`
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CountBean.java PJ:!O?KVq
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/* O:I]v@
* CountData.java *# <%04f
* \
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* Created on 2007年1月1日, 下午4:44 7>im2"zm
* %_n%-Qn
* To change this template, choose Tools | Options and locate the template under ?`OFn F,K
* the Source Creation and Management node. Right-click the template and choose (ID%U
* Open. You can then make changes to the template in the Source Editor. -`ljKp
*/ EyR/
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package com.tot.count; 6{d?3Jk
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/** :!Z |_y{b
* 7`~0j6FY
* @author Vxrj(knck,
*/ Gfx!.[Y
public class CountBean { #5y+gdN
private String countType; %npLgCF
int countId; ({Yfsf,
/** Creates a new instance of CountData */ OS%[SHs
public CountBean() {} 5fs,UH
public void setCountType(String countTypes){ k2loGvBJ
this.countType=countTypes; F+VNrt-
} DNDzK
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public void setCountId(int countIds){ C!547(l[
this.countId=countIds; Uth+4Aq
} $C=XSuPNK
public String getCountType(){ c{`!$Z'k<
return countType; ((AK7hb
} mGg/F&G9
public int getCountId(){ {88|J'*L
return countId; D',7 T=C
} yS
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} IW@xT@
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CountCache.java vS ( Y_6
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/* 3
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* CountCache.java rVhfj~Ts
* (e_p8[x
* Created on 2007年1月1日, 下午5:01 VxOWv8}|
* gs0jwI
* To change this template, choose Tools | Options and locate the template under 1Cc91
* the Source Creation and Management node. Right-click the template and choose /xSJljexz
* Open. You can then make changes to the template in the Source Editor. _)LXD,LA
*/ F~fN7<9R
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package com.tot.count; }X])055S
import java.util.*; LIJ#nb
/** !iHC++D
* NG\'Ii:-J
* @author e|SNb*_
*/ 'G[G;?F
public class CountCache { H{_D#It
public static LinkedList list=new LinkedList(); ~U7Bo(EJp
/** Creates a new instance of CountCache */ qoT&N,/
public CountCache() {} hX,RuI
public static void add(CountBean cb){ 3y$6}Kp4?
if(cb!=null){ ]n@T5*=
list.add(cb); Q6 o1^s
} _8SB+s*
} {{bwmNv"
} |ggtb\W
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CountControl.java Y1AZ%{^0a
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/* AW_ YlS
* CountThread.java z<P?p
* OP= oSfa
* Created on 2007年1月1日, 下午4:57 TXd6o=
* V_^pPBa
* To change this template, choose Tools | Options and locate the template under [T'[7Z
* the Source Creation and Management node. Right-click the template and choose c#?~1@=
* Open. You can then make changes to the template in the Source Editor. 1H%p|'FKA
*/ 1bz^$2/k
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package com.tot.count; O,+9r_Gh
import tot.db.DBUtils; o3GZcH?
import java.sql.*; Nv0a]Am
/** 4a!%eBhX"K
* SH"<f_
* @author um<$L
*/ r.u\qPT&
public class CountControl{ 2u0B=0x
private static long lastExecuteTime=0;//上次更新时间 ETX>wZ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AL&<SxuP
/** Creates a new instance of CountThread */ eC 2~&:$L
public CountControl() {} 04-@c
public synchronized void executeUpdate(){ jpXbFWgN
Connection conn=null; 9!r0uU"
PreparedStatement ps=null; f;+.j/ +
try{ ]4')H;'y
conn = DBUtils.getConnection(); RV]QVA*i
conn.setAutoCommit(false); U![$7k>,pr
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Dbx zqd
for(int i=0;i<CountCache.list.size();i++){ h1B_*L
CountBean cb=(CountBean)CountCache.list.getFirst(); xe.f]a
CountCache.list.removeFirst(); 1NTx?JJfW
ps.setInt(1, cb.getCountId()); rHybP6C<
ps.executeUpdate();⑴ l7<VH z0b
//ps.addBatch();⑵ AU}|o0Ur
} 2A*,9S|Y
//int [] counts = ps.executeBatch();⑶ 4QPHT#e qX
conn.commit(); >#;_Ebl@
}catch(Exception e){ 3*{l^<`:gA
e.printStackTrace(); #;1RStb:zj
} finally{ <JXHg,Q
try{ &{# 6Z
if(ps!=null) { 5yJ~ q
ps.clearParameters(); J?E!\V&U
ps.close(); ]f`UflMO8
ps=null; F}F{/
} sVnq|[ /
}catch(SQLException e){} W<O/LHKHdn
DBUtils.closeConnection(conn); !K= $Q Uq
} p vWj)4e
}
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public long getLast(){ 1 K^-tms
return lastExecuteTime; {65YTt%
} G7GKO
public void run(){ ZOppec1D
long now = System.currentTimeMillis(); 9qzHy}A
if ((now - lastExecuteTime) > executeSep) {
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//System.out.print("lastExecuteTime:"+lastExecuteTime); _ Fk^lDI-
//System.out.print(" now:"+now+"\n"); F7=\*U
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); "*c&[ALw
lastExecuteTime=now; RZ9_*Lq7+
executeUpdate(); YXF^4||j.c
} >$3 =yw%
else{ uVX,[%*P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); |<1A<fU8a
} hr&UD| E=
} ,Cy&tRjR B
} m<;MOS
//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 ulEtZ#O{_
TL-ALtG
类写好了,下面是在JSP中如下调用。 +,i_G?eX
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<% {q&`B
CountBean cb=new CountBean(); 6aAN8wO;b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $fPiR
CountCache.add(cb); 3EA_-?
out.print(CountCache.list.size()+"<br>"); OzxiT +
CountControl c=new CountControl(); !QqVJ a{j
c.run(); od !s5f!
out.print(CountCache.list.size()+"<br>"); QY\'Uu{
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