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: iG[?
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CountBean.java :J(sXKr[C
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/* \/Ij7nD`l%
* CountData.java ZxS&4>.
* mPmB6q%)]
* Created on 2007年1月1日, 下午4:44 \].J-^=
* a%~yol0wO7
* To change this template, choose Tools | Options and locate the template under \OHv|8!EI@
* the Source Creation and Management node. Right-click the template and choose $+:(f{Va*
* Open. You can then make changes to the template in the Source Editor. =%h~/,
*/ S]yvMj_?
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package com.tot.count; {~GR8
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/** u;n(+8sz
* .u< U:*
* @author '>^Xqn
*/ "r-l8r,
public class CountBean { J`Oy .Qu)
private String countType; cztS]dcf>~
int countId; w6EI{
/** Creates a new instance of CountData */ |R'i:=
public CountBean() {} 1-$P0
public void setCountType(String countTypes){ ?*K<*wBw#
this.countType=countTypes; ,ZK]i CGk
} /{G/|a
public void setCountId(int countIds){ ,z66bnjO
this.countId=countIds; (G5xkygR9
} m,NMTyJoz
public String getCountType(){ cTj~lO6
return countType; 5V|tXsy:
} *j<@yG2\gP
public int getCountId(){ g[!Cj,
return countId; C.E[6$oVc
} M1uP\Sa
} ;?8Iys#
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CountCache.java 6`"ZsO
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/* f8!l7{2%q
* CountCache.java sfC@*Y2XT
* +{xG<Wkltz
* Created on 2007年1月1日, 下午5:01 p}8ratmN
* &HxT41pku
* To change this template, choose Tools | Options and locate the template under WLy7'3@
* the Source Creation and Management node. Right-click the template and choose ^I./L)0=}
* Open. You can then make changes to the template in the Source Editor. {Tx 3$eU
*/ H^v{Vo
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package com.tot.count; \DyKtrnm%
import java.util.*; XaGz].Sv
/** M,L@k
* +UaO<L
* @author kv%)K'fU4
*/ d
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public class CountCache { m~Me^yt>}
public static LinkedList list=new LinkedList(); 4[H,3}p9H
/** Creates a new instance of CountCache */ jf7pl8gv
public CountCache() {} Vw?P.4
public static void add(CountBean cb){ Ty}R^cy{d
if(cb!=null){ ]n1D1
list.add(cb); y<uE-4
} v|To+P6b
} y7;
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} h*l4Y!7
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CountControl.java h*waRD
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/* | /#'S&!U
* CountThread.java 2?H@$-x>
* Dtt\~m;AR
* Created on 2007年1月1日, 下午4:57 sKCGuw(mh
* $Q,n+ /
* To change this template, choose Tools | Options and locate the template under Ei|0L$NCg
* the Source Creation and Management node. Right-click the template and choose Deog4Ol"/
* Open. You can then make changes to the template in the Source Editor. d5q4'6o,
*/ vK`S!7x'&
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package com.tot.count; "DzGBu\
import tot.db.DBUtils; &}|0CR.(
import java.sql.*; ^~*8 @v""
/** FP@A;/c
* @d
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* @author mN7&%Z
*/ >2t
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public class CountControl{ z.A4x#>-
private static long lastExecuteTime=0;//上次更新时间 ty9rH=1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @6[x%j/!bt
/** Creates a new instance of CountThread */ l^BEFk;
public CountControl() {} ?PYNE
public synchronized void executeUpdate(){ Cd9t{pQD4
Connection conn=null; C*]AL/
PreparedStatement ps=null; ,FS?"Ni
try{ T*p|'Q`
conn = DBUtils.getConnection(); ;_wMWl0F
conn.setAutoCommit(false); [5-!d!a|st
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,^M]yr*~
for(int i=0;i<CountCache.list.size();i++){ NB3/A"}"02
CountBean cb=(CountBean)CountCache.list.getFirst(); `lvh\[3^
CountCache.list.removeFirst(); yvS^2+jW
ps.setInt(1, cb.getCountId()); s/\XH&KR3V
ps.executeUpdate();⑴ TR|;,A[%v#
//ps.addBatch();⑵ pV_}Or_
} w4`!Te
//int [] counts = ps.executeBatch();⑶ zAu}hVcW
conn.commit(); 6WCmp,*
}catch(Exception e){ wbl${@4
e.printStackTrace(); 8\P
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} finally{ e=-YP8l
try{ @<VG8{
if(ps!=null) { ltP
ps.clearParameters(); [6tR&D#K
ps.close(); .k
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ps=null; ^]KIgGv\
} V_ {vZ/0e
}catch(SQLException e){} enWF7`
DBUtils.closeConnection(conn); Mn-<5 1.%
} _y|[Z;
} rkbl/py
public long getLast(){ 1k0^6gE|
return lastExecuteTime; b,zR5R^D;
} ;;D%
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public void run(){ |c]> Q
long now = System.currentTimeMillis(); 2c!h2$w
if ((now - lastExecuteTime) > executeSep) { Z<w,UvJa
//System.out.print("lastExecuteTime:"+lastExecuteTime); m]E o(P4+
//System.out.print(" now:"+now+"\n"); }#YIl@E
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %+/f'6kR
lastExecuteTime=now; xAFek;GY?
executeUpdate(); NEZH<#
} I4A;
else{ !2/l9SUi
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Cb+P7[X-
} `6dy
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} YAX #O\,
} Y#GT*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 [>Ikitow
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类写好了,下面是在JSP中如下调用。 N=hSqw[
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<% 3AX?B~s
CountBean cb=new CountBean(); 2#,8evH
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =mDy@%yx!
CountCache.add(cb); IJ+O),'
out.print(CountCache.list.size()+"<br>"); kOo>Iy
CountControl c=new CountControl(); -t;?P2
c.run(); Q1]V|S;)X
out.print(CountCache.list.size()+"<br>"); ]Fb8.q5(Y
%>