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: c%&:6QniZ
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CountBean.java wW#}:59}
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/* oN{Z+T :
* CountData.java L1ieaKw
* lmfi
* Created on 2007年1月1日, 下午4:44 {.QEc0-
* @$LWWTr;
* To change this template, choose Tools | Options and locate the template under AI,(z;{P
* the Source Creation and Management node. Right-click the template and choose }&n<uUD H
* Open. You can then make changes to the template in the Source Editor. BB~OqZIP
*/ D&}3$ 7>
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package com.tot.count; f2^r[kPX"
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/** e
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* 89\n;5'f4
* @author Ytz)d/3T
*/ zY|t0H
public class CountBean { /[Z,MG
private String countType; GG@md_
int countId; )=AHf?hn
/** Creates a new instance of CountData */ o3I Tr';
public CountBean() {} r41\r,`Dj
public void setCountType(String countTypes){ pcT:]d[1)
this.countType=countTypes; :cq9f2)
} EX?MA6U
public void setCountId(int countIds){ ^1Zeb$Nw'
this.countId=countIds;
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} Q(<)KZIK
public String getCountType(){ VJdIHsI
return countType; 0JlZs]
} 9[m6Li
public int getCountId(){ :E>HE,1b+
return countId; dHK`eS$sb
} 7VMvF/ap]u
} g>dA$h%
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CountCache.java c0hwc1kv-
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/* f}1&HI8r
* CountCache.java (*oL+ef-C
* l-ct?T_@
* Created on 2007年1月1日, 下午5:01 _~*,m#uxJ
* N5i+3&
* To change this template, choose Tools | Options and locate the template under Dh5X/y
* the Source Creation and Management node. Right-click the template and choose AwslWkd=
* Open. You can then make changes to the template in the Source Editor. \/1<E?Q
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*/ Td G!&:>
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package com.tot.count; ]3g?hM6
import java.util.*; b@S Cn9
/** PB#fP_0C
* mml<9fbH
* @author UN zlN
*/ -5T=:2M
public class CountCache { iVd.f
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public static LinkedList list=new LinkedList(); (cN}Epi(D
/** Creates a new instance of CountCache */ *e-A6Sh
public CountCache() {} emdoA:w+
public static void add(CountBean cb){ {K9/HqH
if(cb!=null){ _>9.v%5cs(
list.add(cb); |b-]n"}c>
} co9 .wB@
} G.(mp<-
} |37
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CountControl.java w9o^s5n
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/* w~
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* CountThread.java >2]JXLq
* 'A:x/iv}^
* Created on 2007年1月1日, 下午4:57 %K>.lh@
* h=(DX5:A
* To change this template, choose Tools | Options and locate the template under
F0:A]`|
* the Source Creation and Management node. Right-click the template and choose ^_ kJKM,
* Open. You can then make changes to the template in the Source Editor. 4H|(c[K;
*/ xj[(P$,P
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package com.tot.count; 55;g1o}}f
import tot.db.DBUtils; T'LIrf
import java.sql.*; sgO'wXcoP
/** +reor@h
*
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* @author i:u1s"3~
*/ [+OnV&
public class CountControl{ D<V~f B
private static long lastExecuteTime=0;//上次更新时间 =e8bNg
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qQ0cJIISb\
/** Creates a new instance of CountThread */ \mV'mZ9>
public CountControl() {} 4E+hRKuo,
public synchronized void executeUpdate(){ KyzFnVH3)
Connection conn=null; ~_s{0g]B
PreparedStatement ps=null; C-Ht(x |
try{ zkO<-w
conn = DBUtils.getConnection(); ei6AV1| p
conn.setAutoCommit(false); h;-yU.(w
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); T}4/0yR2
for(int i=0;i<CountCache.list.size();i++){ F35#dIs`&
CountBean cb=(CountBean)CountCache.list.getFirst(); 2^)1N>"g
CountCache.list.removeFirst(); S6fL>'uQ
ps.setInt(1, cb.getCountId()); ak:ibV
ps.executeUpdate();⑴ E@P %v{)
//ps.addBatch();⑵ Qu7T[<
} >P/][MT
//int [] counts = ps.executeBatch();⑶ ]ix!tb.Q
conn.commit(); @"o@}9=d
}catch(Exception e){ #'q<v"w
e.printStackTrace(); v*9<c{a
} finally{ 3 q`)*
try{ E=cwq"
if(ps!=null) { ;s~X
ps.clearParameters(); MdXchO-Lyc
ps.close(); BSkDpr1C
ps=null; WyZL9K{?
} M4d47<'*~
}catch(SQLException e){} PI*82,f3dE
DBUtils.closeConnection(conn); &R$CZU
} JR@.R
,rII
} j~FD{%4N
public long getLast(){ ~j-cS
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return lastExecuteTime; #Jna6
} +Y
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public void run(){ yB3;
long now = System.currentTimeMillis(); h(F<h_
if ((now - lastExecuteTime) > executeSep) { =i(?deR
//System.out.print("lastExecuteTime:"+lastExecuteTime);
!xwG%{_
//System.out.print(" now:"+now+"\n"); 1]}#)-
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 8HZs>l
lastExecuteTime=now; YFTjPBV
executeUpdate(); iR\Hv'|
} Uz7^1.-g4
else{ 0v]?6wX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); l$YC/bP
} b9"jtRTdz
} >/#KI~}'N
} 3
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//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 _$p$")
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类写好了,下面是在JSP中如下调用。 OKHX)"j\\
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<% >+mD$:L
CountBean cb=new CountBean(); )NO<s0?&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8&Myva
CountCache.add(cb); &bhq`>
out.print(CountCache.list.size()+"<br>"); h1(j2S`:
CountControl c=new CountControl(); 8v71e>
c.run(); 93<:RV
out.print(CountCache.list.size()+"<br>"); LPwT^zV&N
%>