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: d-$/C| J
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CountBean.java _O>8jH!#
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/* ?(j:F2dU~
* CountData.java r(/+-
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* Lc13PTz>>g
* Created on 2007年1月1日, 下午4:44 oyo
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* Z|$OPMLX
* To change this template, choose Tools | Options and locate the template under }JBLzk5|
* the Source Creation and Management node. Right-click the template and choose {o.i\"x;
* Open. You can then make changes to the template in the Source Editor. +#
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*/ VH$hQPP5d
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package com.tot.count; 7-MkfWH2b6
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/** !qVnziE,,
* 8 gzf$Oc
* @author $r=tOD4;
*/ /%T d(
public class CountBean { .t|B6n!
private String countType; VpmD1YSn
int countId; G>c:+`KS
/** Creates a new instance of CountData */ ,hXhcfFl
public CountBean() {} Ln5g"g8gb%
public void setCountType(String countTypes){ $"]*,=-X
this.countType=countTypes; AtW<e;!0te
} "\M^jO
public void setCountId(int countIds){ S-KHot ?
this.countId=countIds; p v*n.U6
} $n@B:kv5p
public String getCountType(){ L)j<;{J/Q0
return countType; MFm2p?zPm
} <ULydBom
public int getCountId(){ 'z3I*[!
return countId; +OC~y:
} q`^T7
} E >lW'
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CountCache.java O;?Nz:/q
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/* %.VFj7J
* CountCache.java T:(c/>
* 'Q F@@ 48
* Created on 2007年1月1日, 下午5:01 #Vi:-zyY
* `E2HQA@
* To change this template, choose Tools | Options and locate the template under Z`Sbq{Kx
* the Source Creation and Management node. Right-click the template and choose L4-v'Z;
* Open. You can then make changes to the template in the Source Editor. :LEC[</yvl
*/ As-xO~ +
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package com.tot.count; ae|j#!~oi
import java.util.*; K/ 5U;oC
/** 1=Nh<FuQ
* ct![eWsuB
* @author ~zT7 43
*/ R\d)kcy4
public class CountCache { B(h%>mT[
public static LinkedList list=new LinkedList(); |QB[f*y5
/** Creates a new instance of CountCache */ !U8n=A#,-
public CountCache() {} >crFIkOJ
public static void add(CountBean cb){ _/`H<@B_U
if(cb!=null){ q,v)X
list.add(cb); 9S]]KEGn4
} Cmj+>$')0
} "8sB,$
} 7S]<?>*
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CountControl.java r`GA5}M
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/* ?,0 a#lG
* CountThread.java *$yU|,
* 's_[#a;Vp
* Created on 2007年1月1日, 下午4:57 @ UCr`>
* ;fGh]i
* To change this template, choose Tools | Options and locate the template under ]
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* the Source Creation and Management node. Right-click the template and choose {f:%+h
* Open. You can then make changes to the template in the Source Editor. WYXh1_nyk
*/ '| rhm
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package com.tot.count;
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import tot.db.DBUtils; e'0BP,\f_}
import java.sql.*; Uon^z?0A
/** ?0J&U4
* c$#7Kp4
* @author -#<AbT
*/ Cu&y',ee~
public class CountControl{ zVyMmw\
private static long lastExecuteTime=0;//上次更新时间 -"~XI~a@Wo
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {7Q)2NC
/** Creates a new instance of CountThread */ b:t|9FE%
public CountControl() {} j;SK{Oq
public synchronized void executeUpdate(){ fobnK~2
Connection conn=null; @Tz}y"VG
PreparedStatement ps=null; [H5BIM@{
try{ $~5ax8u&!#
conn = DBUtils.getConnection(); OH/!Ky\@
conn.setAutoCommit(false); 6Mh"{N7
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); #Q'j^y7=z
for(int i=0;i<CountCache.list.size();i++){ V18A|]k
CountBean cb=(CountBean)CountCache.list.getFirst(); ^LAnR>mz^r
CountCache.list.removeFirst(); hYB3tT
ps.setInt(1, cb.getCountId()); &.1qixXIr
ps.executeUpdate();⑴ N/6!|F
//ps.addBatch();⑵ ^Cy=L]
} <kOdd)X
//int [] counts = ps.executeBatch();⑶ uyDPWnYk
conn.commit(); <`'T#e$
}catch(Exception e){ 5/YGu=,
e.printStackTrace(); ^i8"eF
} finally{ u%sfHGrH
try{ hh7unHt-
if(ps!=null) { {j[a'Gb
ps.clearParameters(); JBk >|q"
ps.close(); ^aR^M\38
ps=null; []b=
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} SQs+4YJ
}catch(SQLException e){} n4InZ!)
DBUtils.closeConnection(conn); p!>DA?vF
} /^hc8X
} Aa4 DJ
public long getLast(){ r&3EM[*Iw
return lastExecuteTime; %fMFcL#h
} N.UeuLz
public void run(){ ,xI
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long now = System.currentTimeMillis(); 9v@P|
if ((now - lastExecuteTime) > executeSep) { i+ICgMcd
//System.out.print("lastExecuteTime:"+lastExecuteTime); "DvhAEM
//System.out.print(" now:"+now+"\n"); F4DJML-(
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]8f$&gw&A
lastExecuteTime=now; Dgc}T8R
executeUpdate(); q1pB~eg5
} OEnCN
else{ 7Fzj&!>ti
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sT'j36Nc<,
} 08G${@D+X0
} U(/8dCyyY
} V@o#" gZ
//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 {5Sy=Y
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类写好了,下面是在JSP中如下调用。 J_ 7#UjGA,
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<% bXi(]5
CountBean cb=new CountBean(); suHisc*
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); L@"&s#~=3
CountCache.add(cb); {uN-bl?o
out.print(CountCache.list.size()+"<br>"); 7:e5l19 uI
CountControl c=new CountControl(); Y_nl9}&+C0
c.run(); GB4^ 4Ajx
out.print(CountCache.list.size()+"<br>"); B&m6N,
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