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: H}Jdnu| ko
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CountBean.java a5)<roWQ
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/* b`lLqV<[cB
* CountData.java >q}Ns^ .'
* d4 Hpe>
* Created on 2007年1月1日, 下午4:44 Wk0"U
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* rx$B(z(c
* To change this template, choose Tools | Options and locate the template under +b9gP\Hke
* the Source Creation and Management node. Right-click the template and choose N=JZtf/i
* Open. You can then make changes to the template in the Source Editor. -L.U4x
*/ ![>j`i
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package com.tot.count; CTNeh%K;
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/** 2"'<Yk9
* ?!uj8&yyf
* @author <]SI-
*/ BA5b;+o-
public class CountBean { ZFJqI
private String countType; o'Uaz*-po
int countId; Ib~n}SA
/** Creates a new instance of CountData */ *VbB'u:
public CountBean() {} <hJ%]]
public void setCountType(String countTypes){ aX)k(*|
this.countType=countTypes; aJ4y%Gy?
} fcim4dfP
public void setCountId(int countIds){ >dr34=(
this.countId=countIds; r Ljb'\<*
} ;Nd,K
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public String getCountType(){ r?:zKj8/u
return countType; $=IJ-_'o
} F*0rpQ,*
public int getCountId(){ 3eg)O34
return countId; Wubvvm8U
} "-WEUz
} w;p:4`
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CountCache.java }#b[@3/T
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/* cLZaQsS%
* CountCache.java ! U6 x_
* Xcy Xju#"p
* Created on 2007年1月1日, 下午5:01 d'x'hp%
* wa)E.(x
* To change this template, choose Tools | Options and locate the template under (>LJv |wn
* the Source Creation and Management node. Right-click the template and choose oZ/z{`
* Open. You can then make changes to the template in the Source Editor. /^2&@P7
*/ lCX*Q{s22
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package com.tot.count; HW@r1[Y
import java.util.*; )Rlh[Y& r
/** 3YFbT
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* ^z _m<&r
* @author # },4m
*/ DJ!<:9FD
public class CountCache { R)>F*GsR
public static LinkedList list=new LinkedList(); ?}n\&|+
/** Creates a new instance of CountCache */ &nRbI:R
public CountCache() {} qgk-[zW#
public static void add(CountBean cb){ %VSjMZ
if(cb!=null){ odm!}stus
list.add(cb); c9
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} {SQ#n@Q&$
} d:_3V rRZ
} /'ukeK+'
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CountControl.java H2cY},
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/* 8iIz!l%O
* CountThread.java k>'c4ay290
* 3jJd)C R
* Created on 2007年1月1日, 下午4:57 ` 465
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* Gy3t
* To change this template, choose Tools | Options and locate the template under -Y{=bZS u
* the Source Creation and Management node. Right-click the template and choose pSPVY2qKX
* Open. You can then make changes to the template in the Source Editor. hd'JXKMy
*/ Za>0&Fnf
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package com.tot.count; -!ARVf *
import tot.db.DBUtils; mj!P
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import java.sql.*; 9iwSE(},
/** z5UY0>+VdS
* g?mfpw Zj
* @author s (hJ *
*/ '1Z3MjX
public class CountControl{ #\{j/{VZ
private static long lastExecuteTime=0;//上次更新时间 G'dN_6ho3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 c:@lR/oe"
/** Creates a new instance of CountThread */ 8etNS~^
public CountControl() {} ^p2_p9
public synchronized void executeUpdate(){ 1pDL()t
Connection conn=null; v!~ ;QO
PreparedStatement ps=null; G(*7hs
try{ S+LS!b
conn = DBUtils.getConnection(); O^_$cq
conn.setAutoCommit(false); fPj*qi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9P)28\4
for(int i=0;i<CountCache.list.size();i++){ W,53|9b@
CountBean cb=(CountBean)CountCache.list.getFirst(); `:4bg1u
CountCache.list.removeFirst(); k/`WfSM\.
ps.setInt(1, cb.getCountId()); [3~mil3rO
ps.executeUpdate();⑴ 0c,)T1NG >
//ps.addBatch();⑵ ~R$Ko(N
} pAY[XN
//int [] counts = ps.executeBatch();⑶ o=}vK[0u
conn.commit(); yf/c
}catch(Exception e){ Bm\OH#
e.printStackTrace(); sT;:V
} finally{ ^gu;
try{ >~vZ+YO
if(ps!=null) { Di^7@}kQS
ps.clearParameters(); H*H=a
ps.close(); _-mJI+^/
ps=null; ]CnqPLqL
} -:P`Rln
}catch(SQLException e){} E979qKl
DBUtils.closeConnection(conn); $YPQi.
} c1 ~=
} <:YD.zAh|
public long getLast(){ G^6\ OOSy
return lastExecuteTime; .>;}GsN&
} fN-y8
public void run(){ IW&.JNcN
long now = System.currentTimeMillis(); aP}%&{iC*
if ((now - lastExecuteTime) > executeSep) { h]w5N2$}?
//System.out.print("lastExecuteTime:"+lastExecuteTime); qbunP!
//System.out.print(" now:"+now+"\n"); pRTdP/(OQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .o"FT~}z
lastExecuteTime=now; xtN=?WjVe0
executeUpdate(); wvuh
} B+pJWl8u
else{ Kd%>:E*
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); l4LowV7
} U*R
} }w%W A&"W
} &l| :1
//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 ->0OqVQA
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类写好了,下面是在JSP中如下调用。 B*,Qw_3dG
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<% g218%i
CountBean cb=new CountBean(); NU#rv%p
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ;<~lzfs
CountCache.add(cb); B;6N.X(K
out.print(CountCache.list.size()+"<br>"); @?gN
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CountControl c=new CountControl(); {R{Io|
c.run(); ;=ci7IT'
out.print(CountCache.list.size()+"<br>"); *]uj0@S
%>