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=P}@| K
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CountBean.java }_9yemP
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/* YZ/2:[b
* CountData.java 'F Cmbry
* l +#FoN
* Created on 2007年1月1日, 下午4:44 E5t
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* W-4R;!42
* To change this template, choose Tools | Options and locate the template under 94u~:'t>V
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. 'OsRQ)E
*/ '2ACZcjDSv
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package com.tot.count; _*u$U
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/** !~ZAm3GwL
* 3U[:N
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* @author 7G
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*/ |:Lk lpdYe
public class CountBean { m/ngPeZ
private String countType; 3ZX#6*(}2
int countId; He LW*
/** Creates a new instance of CountData */ Ap!i-E,"J
public CountBean() {} !w:pb7+G
public void setCountType(String countTypes){ E#c9n%E\sz
this.countType=countTypes; D]+@pKb
} rVDOco+w
public void setCountId(int countIds){ 2mfG:^^c
this.countId=countIds; x3 01uf[
} Q`z2SYz>
public String getCountType(){ 9PJnKzQ4
return countType; muIJeQ.C
} Rh{`#dI~=
public int getCountId(){ 5O:4-}hz
return countId; ]nm(V
} lrK?&a9AB
}
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CountCache.java =wFl(Q6J
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/* ,?VYrL
* CountCache.java 8k?V&J `
* LBnlaH.
* Created on 2007年1月1日, 下午5:01 fY 10a_@x
* km6O3>p5r
* To change this template, choose Tools | Options and locate the template under 4 }*V=>z
* the Source Creation and Management node. Right-click the template and choose Bn*QT:SKC
* Open. You can then make changes to the template in the Source Editor. N'I9J?e Q
*/ I\('b9"*
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package com.tot.count; "VA'W/yv!
import java.util.*; R{{?wr6b$
/** XZj3x',;
* [.nkNda5)v
* @author (O'O#AD
*/ zz-X5PFn
public class CountCache { 8n/[oDc]
public static LinkedList list=new LinkedList(); Nd**":i$
/** Creates a new instance of CountCache */ M#xol/)h
public CountCache() {} UW-`k1
public static void add(CountBean cb){ ^'4I%L"
if(cb!=null){ d@{#F"o
list.add(cb); ]NY^0SqM
} N`7+]T
} /n3S E0Y
} P7;q^jlB
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CountControl.java )H%RwV#
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/* Y$FhV~m
* CountThread.java L^L.;1
* >,nK
* Created on 2007年1月1日, 下午4:57 N7Kkz
/
* E=qfI>2U&
* To change this template, choose Tools | Options and locate the template under /!W',9ua6
* the Source Creation and Management node. Right-click the template and choose L}>ts(!q&
* Open. You can then make changes to the template in the Source Editor. K#dG'/M|Pb
*/ @mEB=X(-l=
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package com.tot.count; j]6YLM@5$
import tot.db.DBUtils; gflO0$i
import java.sql.*; p
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/** h BzZJ/jn
* ! Y'~?BI
* @author |6~ Kin
*/ ^aY,Wq
public class CountControl{ ?r^>Vk}
private static long lastExecuteTime=0;//上次更新时间 *ub"!}$st
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 c1g'l.XL
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/** Creates a new instance of CountThread */ 8!7`F.BX
public CountControl() {} >%85S >e
public synchronized void executeUpdate(){ U6~79Hnt
Connection conn=null; (o1o);AO
PreparedStatement ps=null; D^A#C<Gs
try{ C40W@*6S2
conn = DBUtils.getConnection(); T,v5cc:nO
conn.setAutoCommit(false); G[Jz(/yNH
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); TGI`}#
for(int i=0;i<CountCache.list.size();i++){ q(}#{OO
CountBean cb=(CountBean)CountCache.list.getFirst(); M[^EHa<i
CountCache.list.removeFirst(); ? 1Uq ud
ps.setInt(1, cb.getCountId()); ;i&t|5y~
ps.executeUpdate();⑴ r\m2Oo)]
//ps.addBatch();⑵ !GtCOr\'
} 6jz~q~I
//int [] counts = ps.executeBatch();⑶ &a";jO
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conn.commit(); `5Em : 8 M
}catch(Exception e){ ]!cLFXa
e.printStackTrace(); d>x(Bj6
} finally{ T@Th?
try{ BU=Ta$#BZ
if(ps!=null) { u$+nl~p[&
ps.clearParameters(); NzbHg p
ps.close(); MDfC%2Q
ps=null; )7a
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}
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}catch(SQLException e){} +aRHMH
DBUtils.closeConnection(conn); X/23 /_~L`
} &5R-bYGW
} I =nvL
public long getLast(){ QE`u~
return lastExecuteTime; >@q4Uez
} |JTDwmR
public void run(){ Tywrh9[
long now = System.currentTimeMillis(); g715+5z[
if ((now - lastExecuteTime) > executeSep) { "mAMfV0
//System.out.print("lastExecuteTime:"+lastExecuteTime); VPOp#;"%
//System.out.print(" now:"+now+"\n"); VBe&of+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }1Pv6L(o)
lastExecuteTime=now; jW]Fx:mQi
executeUpdate(); iayxN5,
} }K9Ji]tOK:
else{ 7OLchf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} ':|?M B
} #v:A-u
} #YB3Ug]z
//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 )!d_Td\-
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类写好了,下面是在JSP中如下调用。 _kQOax{c/
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<% qEnmms 1
CountBean cb=new CountBean(); :47"c3J
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O\^D
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CountCache.add(cb); x!A5j
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out.print(CountCache.list.size()+"<br>"); ;`FR1KIg
CountControl c=new CountControl(); dlc'=M
c.run();
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out.print(CountCache.list.size()+"<br>"); B[[1=
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