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: [,aqQ6S
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CountBean.java (LtkA|:
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/* &|<xqt
* CountData.java >l+EJ3W
* ,b$2= JO'f
* Created on 2007年1月1日, 下午4:44 {@u<3 s
* XIWm>IQ[)
* To change this template, choose Tools | Options and locate the template under o."rxd
* the Source Creation and Management node. Right-click the template and choose Sc]P<F7N]
* Open. You can then make changes to the template in the Source Editor. 2Nj9U#A
*/ [Lp,Hqi5
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package com.tot.count; %Z8vdU# l
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/** K{l5m{:%
* S
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* @author cMzkL%
*/ \NqEw@91B
public class CountBean { `E\imL
private String countType; |7^^*UzSK:
int countId; UHGcnz<
/** Creates a new instance of CountData */ Y&2aO1
public CountBean() {} ba@=^Fa;
public void setCountType(String countTypes){ 7rHS^8'H&
this.countType=countTypes; wVq\FY%
} GPWr>B.{:S
public void setCountId(int countIds){ 'ho{eR@d
this.countId=countIds; g8'DoHJ*
} M3zDtN
public String getCountType(){ |8)Xc=Hz
return countType; I|/'Ds:
} Be}$I_95\P
public int getCountId(){ 8#` 6M5
return countId; E:nt)Ef,
} oH2!5;A|
} gZT)pP
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CountCache.java 9B)(>~q
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/* Bfd-:`Jk
* CountCache.java j|e[s ?d
* QT#6'>&7-b
* Created on 2007年1月1日, 下午5:01 nB5Am^bP
* wE).>
* To change this template, choose Tools | Options and locate the template under M@p"yq
* the Source Creation and Management node. Right-click the template and choose (P==VZQg
* Open. You can then make changes to the template in the Source Editor. 1'G8o=~
*/ %q_Miu@
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package com.tot.count; 7?)/>lx\>$
import java.util.*; :Y)to/h
/** (RXS~8
* {Ts:ZI+
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* @author ^^(<c,NX#M
*/ ;5<-)
public class CountCache { tLcEl'Eo
public static LinkedList list=new LinkedList(); !5x
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/** Creates a new instance of CountCache */ S)%_we LW7
public CountCache() {} A6ewdT?>,
public static void add(CountBean cb){ Qrz4}0
if(cb!=null){ #X.+
list.add(cb); ~DLIz g7p!
} 'Zk<l#"}
} eSl-9
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} 3z{S}~
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CountControl.java M+sj}
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/* 'nK~'PZ,
* CountThread.java PdY>#Cyh
* ^ua12f
* Created on 2007年1月1日, 下午4:57 +zWrLf_Rc
* ;^l_i4A
* To change this template, choose Tools | Options and locate the template under w 7tC|^#G
* the Source Creation and Management node. Right-click the template and choose |Vx~fK S\
* Open. You can then make changes to the template in the Source Editor. -O&"|
*/ z^sST
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package com.tot.count; S 2$5!(P
import tot.db.DBUtils; .#^0pv!
import java.sql.*; xKp0r1}
/** L)-*,$#<oW
* n_$yV:MuT!
* @author 6CNS%\A
*/ ^{[`=P'/
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 @~jxG%y86
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zj]b&In6;
/** Creates a new instance of CountThread */ )LswSV
public CountControl() {} ccO
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public synchronized void executeUpdate(){ A|<;
Connection conn=null; 7o{*Z
PreparedStatement ps=null; @)sc6
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try{ D6!t VdnVe
conn = DBUtils.getConnection(); jXEGSn
conn.setAutoCommit(false); T2bnzIi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Mr6E/7g%
for(int i=0;i<CountCache.list.size();i++){ :'w?ye[e
CountBean cb=(CountBean)CountCache.list.getFirst(); o_yRn16
CountCache.list.removeFirst(); xQz#i-v
ps.setInt(1, cb.getCountId()); ^now}u9S6
ps.executeUpdate();⑴ NyJnOw(
//ps.addBatch();⑵ 4/L>&%8V
} umDtp\
//int [] counts = ps.executeBatch();⑶ *1;23BiH-
conn.commit(); *5wv%-
}catch(Exception e){ 3c 28!3p
e.printStackTrace(); b~!om
} finally{ ug6r]0]
try{ WzG07 2w
if(ps!=null) { -Uf4v6A
ps.clearParameters(); II#
ps.close(); q[boWW
ps=null; ZA.fa0n
} z\[(g
}catch(SQLException e){} `2x 34
DBUtils.closeConnection(conn); DS
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} #v qz{R~nM
} x_ySf!ih
public long getLast(){ k
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return lastExecuteTime; J%4HNW*p
} 70<K.T<b
public void run(){ /s-d?
long now = System.currentTimeMillis(); luF#OP C
if ((now - lastExecuteTime) > executeSep) { $f(agG]
//System.out.print("lastExecuteTime:"+lastExecuteTime); G4yUC<TqBP
//System.out.print(" now:"+now+"\n"); 5TET<f6R
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s1@@o#r
lastExecuteTime=now; ew"m!F#
executeUpdate(); B_@7IbB
} -eYL*Pa
else{ nE<J`Wo$f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RQ5P}A
3H
} c+;S<g0
} 4H7Oh*P\j
} IuWX*b`v
//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 LO>8 j:
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类写好了,下面是在JSP中如下调用。 cX"G7Bh
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<% ^=#!D[xj>
CountBean cb=new CountBean(); q/J3cXa{K
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8AX3C s_G
CountCache.add(cb); g!5#,kJM
out.print(CountCache.list.size()+"<br>"); 0sabh`iQ^
CountControl c=new CountControl(); cV(H<"I
c.run(); ]84YvpfW
out.print(CountCache.list.size()+"<br>"); QZYM9a>
%>