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: _KlPbyLU
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CountBean.java -1Ki7|0,
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/* SZ1pf#w!
* CountData.java _[6+FdS],
* os0"haOI9h
* Created on 2007年1月1日, 下午4:44 'G
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* k1
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* To change this template, choose Tools | Options and locate the template under [_z2z6
* the Source Creation and Management node. Right-click the template and choose S&g-
* Open. You can then make changes to the template in the Source Editor. <
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*/ 3jQ$72_
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package com.tot.count; MZ#2WP)F
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/** |x~ei_x7.p
* @;-Un/'C;7
* @author b+fy&rk@-
*/ S}oF7;'Ga
public class CountBean { r_2VExk
private String countType; bu!<0AP"N+
int countId; [ZpG+VAJ8
/** Creates a new instance of CountData */ a~+WL
public CountBean() {} XwqfWd_
public void setCountType(String countTypes){
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this.countType=countTypes; "gVH;<&]
} <Ucfd
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public void setCountId(int countIds){ uY#58?>'j
this.countId=countIds; b8xfV{3 L
} Bk(XJAjY
public String getCountType(){ dXy"yQ>{
return countType; 2T?1X{g
} Vam8NnZ|r
public int getCountId(){ ErUk>V
return countId; .*..pf|/
} ?J1&,'&
} >WG91b<Xq
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CountCache.java E;*TRr><
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/* K>E!W!-PJ
* CountCache.java J};,%q_
* ;R>42
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* Created on 2007年1月1日, 下午5:01 Q? |M BTo
* k{&E}:A
* To change this template, choose Tools | Options and locate the template under w\[*_wQp
* the Source Creation and Management node. Right-click the template and choose sJ*U Fm{
* Open. You can then make changes to the template in the Source Editor. vG=$UUh@~
*/ LGue=Hkp
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package com.tot.count; fXR_)d
import java.util.*; )=y6s^}
/** |Szr=[
* \d8=*Zpz7
* @author
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*/ M(gWd8?#
public class CountCache { )Syf5I
public static LinkedList list=new LinkedList(); G\+MT(&5
/** Creates a new instance of CountCache */ Lr]Hvd
public CountCache() {} Jywz27j
public static void add(CountBean cb){ \^Q)`Lqp:g
if(cb!=null){ Z#t.wWSq
list.add(cb); E<[
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} mLdyt-1
} eyp\h8!u_
} @Pg@ltUd
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CountControl.java >.sN?5}y
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/* {dH<Un(4Z
* CountThread.java Z4tq&^ :c=
* <JuJ`t
* Created on 2007年1月1日, 下午4:57 3S21DC@Y
* xVo)!83+Q
* To change this template, choose Tools | Options and locate the template under "uNxKLDB
* the Source Creation and Management node. Right-click the template and choose ^qy-el
* Open. You can then make changes to the template in the Source Editor. _A~gqOe
*/ \r&@3a.>
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package com.tot.count; FK('E3PG
import tot.db.DBUtils; tAn6pGp
import java.sql.*; DccsVR`7
/** q.Mck9R7
* !S}Au Mw
* @author @_Oe`j^
*/ Z9EQ|WfS#-
public class CountControl{ _ o3}Ly}
private static long lastExecuteTime=0;//上次更新时间 c.> (/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 fXQRsL8
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/** Creates a new instance of CountThread */ "C|l3X'
public CountControl() {} CzbNG^+
public synchronized void executeUpdate(){ +u)$o
Connection conn=null; PA[Rhoit,
PreparedStatement ps=null; s&hP^tKT
try{ `h]f(
conn = DBUtils.getConnection(); JQ4>S<ttJ
conn.setAutoCommit(false); +`[Sv%v&L
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); P.P>@@+d
for(int i=0;i<CountCache.list.size();i++){ I8:&Btf
CountBean cb=(CountBean)CountCache.list.getFirst(); ${2fr&Tp
CountCache.list.removeFirst(); XOFaS '.
ps.setInt(1, cb.getCountId()); H2KY$;X[
ps.executeUpdate();⑴ d+)L\
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//ps.addBatch();⑵ |}Lgo"cTC
} &1Iy9&y
//int [] counts = ps.executeBatch();⑶ B)NB6dCp
conn.commit(); (ytkq(
}catch(Exception e){ I(S6DkU
e.printStackTrace(); N#ObxOE6T"
} finally{ \mGM#E
try{ Ji=iq=S7
if(ps!=null) { DgP%Q
ps.clearParameters(); vGDo?X~#o
ps.close(); 9^olAfX`dB
ps=null; m@?e
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} Z}f_\d'
}catch(SQLException e){} S!cXc/H-R
DBUtils.closeConnection(conn); e8v=n@0
} p$<qT^]&
} a06q-3zw
public long getLast(){ %tLq&tyeY
return lastExecuteTime; Jp0.h8i
} jXR+>=_
public void run(){ <rF
long now = System.currentTimeMillis(); 7mBL#T2
if ((now - lastExecuteTime) > executeSep) { >4b39/BM
//System.out.print("lastExecuteTime:"+lastExecuteTime); z5/O8}Gz@
//System.out.print(" now:"+now+"\n"); </p.OaNe
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); \]El%j4
lastExecuteTime=now; CB1u_E_
executeUpdate(); &o.SmkJI
} z w9r0bG
else{ m8'1@1d|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7F~+z7(h
} h#nQd=H<g#
} _%B`Y ?I`
} E]Q)pZ{Jb
//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 BD+?Ad?
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类写好了,下面是在JSP中如下调用。 7L"/4w
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<% sxtGl^,mU:
CountBean cb=new CountBean(); 1L7,x @w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 5K<C
CountCache.add(cb); 4N&}hOM'S
out.print(CountCache.list.size()+"<br>"); 2D"/k'iA
CountControl c=new CountControl(); O/nS,Ux
c.run(); nt6"}vO
out.print(CountCache.list.size()+"<br>"); @d|9(,Q
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