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: ~}5Ml_J$,l
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CountBean.java ^-IsK#r.k
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/* ;1.>"zX(
* CountData.java mbBRuPEa=u
* R1.sq(z`
* Created on 2007年1月1日, 下午4:44 @ >(u:.
* i$ L]X[
* To change this template, choose Tools | Options and locate the template under eUkoVr
* the Source Creation and Management node. Right-click the template and choose JQ_gM._3
* Open. You can then make changes to the template in the Source Editor. {%_j~
*/ 5(|M["KK~
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package com.tot.count; Z02s(y=k1
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/** z`/.v&<>V
* #Q3PzDfj
* @author RW7oL:$dt
*/ c[ony:6
public class CountBean { =$8@JF'
private String countType; [S]!+YBK
int countId; d=Do@)
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/** Creates a new instance of CountData */ cIr1"5POXK
public CountBean() {} wz+5
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public void setCountType(String countTypes){ 0sd-s~;
this.countType=countTypes; +V9B
} ^
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public void setCountId(int countIds){ jRG\C=&(x
this.countId=countIds; fT3*>^Uv
} 5Vi]~dZu7
public String getCountType(){ JblmXqtC
return countType; n`)7Y`hBhP
} (s"iC:D6U
public int getCountId(){ C6d]tLE
return countId; 'yd@GQM&
} 90T%T2K
} yIIETE
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CountCache.java A*;?U2
cVay=5].
/* -@L's{J{M
* CountCache.java "]m*816'
* v'@b. R,
* Created on 2007年1月1日, 下午5:01 *sw-eyn(
* (
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* To change this template, choose Tools | Options and locate the template under MdH97L)L.0
* the Source Creation and Management node. Right-click the template and choose ]iDJ*!I
* Open. You can then make changes to the template in the Source Editor. uyNJN
*/ Vd+Q:L
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package com.tot.count; S9p?*
import java.util.*; h `ME(U~<<
/** BMNr<P2li
* 9&%#nN4`8
* @author n}A?jOSAe
*/ xHB/]Vd-
public class CountCache { o-~~,n\
public static LinkedList list=new LinkedList(); nMGrG
/** Creates a new instance of CountCache */ |rFR8srPG
public CountCache() {} -2\ZzK0tM
public static void add(CountBean cb){ 5r4gmy>
if(cb!=null){ lRDxIuTK
list.add(cb); i_u
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} 2L2 VVO
} 1n'$Ji7
} #SQvXMT
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CountControl.java 1TNz&=e
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/* 0||"r&:X
* CountThread.java
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* $_C+4[R?
* Created on 2007年1月1日, 下午4:57 URK!W?3c
* rLJ[FqS
* To change this template, choose Tools | Options and locate the template under &$qF4B*
* the Source Creation and Management node. Right-click the template and choose
\Mb(6~nC
* Open. You can then make changes to the template in the Source Editor. hCM8/Vvx6
*/ CE#\Roi x)
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package com.tot.count; M
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import tot.db.DBUtils; _BV`,`8}
import java.sql.*; QqtC`H\
/** Hz?!BV0
* >z=Ou<,
* @author Zx+cvQ
*/ rH_Jh}Y
public class CountControl{ lq>pH5x
private static long lastExecuteTime=0;//上次更新时间 YwL`>?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pe()f/Jx(
/** Creates a new instance of CountThread */ 2{ o0@
public CountControl() {} [ -ISR7D
public synchronized void executeUpdate(){ |2)Sd[q
Connection conn=null; dEASvD'
PreparedStatement ps=null; lC#RNjDp/~
try{ G02ox5X
conn = DBUtils.getConnection(); e?V,fzg
conn.setAutoCommit(false); ~G>jw"r
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); TbLe6x
for(int i=0;i<CountCache.list.size();i++){ vv+D*e&<
CountBean cb=(CountBean)CountCache.list.getFirst(); A&?}w_|9
CountCache.list.removeFirst(); [p ii
ps.setInt(1, cb.getCountId()); 3Y
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ps.executeUpdate();⑴ 5W+{U8\
//ps.addBatch();⑵ +UxI{,L
} {A|bBg1!
//int [] counts = ps.executeBatch();⑶ =fl%8"%N&
conn.commit(); SLkuT`*
}catch(Exception e){ sVu k
e.printStackTrace(); .H8mRvd?
} finally{ %}C9
try{ &1wpGJqm
if(ps!=null) { rA,CQypo
ps.clearParameters(); Xv0F:1
ps.close(); &hayR_F9
ps=null; cd!|Ne>fe
} S5N@\ x
}catch(SQLException e){} 3bH~';<
DBUtils.closeConnection(conn);
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} '61i2\[lZQ
} 91up^
public long getLast(){ x;u ~NKy
return lastExecuteTime; 4O!E|/`wO
} F>N+<Z
public void run(){ t5paYw-b
long now = System.currentTimeMillis(); R"*R99
if ((now - lastExecuteTime) > executeSep) { 0q{[\51*
//System.out.print("lastExecuteTime:"+lastExecuteTime); IAI(Ix
//System.out.print(" now:"+now+"\n"); Ikj=`,a2B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y0@yD#,0~
lastExecuteTime=now; *Bs^NU.
executeUpdate(); ic-IN~J-
} ASW4,% cl
else{ ivfXat-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); #{x5L^v>]
} @l~7x
} "tL2F*F"6X
} 7 _g+^e-"
//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 x;j{}
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类写好了,下面是在JSP中如下调用。 66Gx.tE
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<% Z:@6Lv?CN
CountBean cb=new CountBean(); _gW{gLYyJ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )lh8
k{
CountCache.add(cb); IaLMWoh
out.print(CountCache.list.size()+"<br>"); h4(JUio
CountControl c=new CountControl(); *69c-`o
c.run(); j0FW8!!-g
out.print(CountCache.list.size()+"<br>"); 3B{[%#vO
%>