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: whvM^
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CountBean.java -V<i4X<|,+
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/* D<nTo&m_
* CountData.java ;g?5V
* %xkqiI3Ff
* Created on 2007年1月1日, 下午4:44 Uu8Z2M
* =<R77rnY&
* To change this template, choose Tools | Options and locate the template under V=.lpj9m
* the Source Creation and Management node. Right-click the template and choose aCy2.Qn
* Open. You can then make changes to the template in the Source Editor. naM4X@jl
*/ +g\u=&<6
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package com.tot.count; Z}$.Tm
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/** 7$;mkHu4H%
* /?HRq ?n
* @author lvcX}{>\
*/ Y#NlbKkzu
public class CountBean { r'k-*I
private String countType; !dSY?1>U<
int countId; f4]nz:2
/** Creates a new instance of CountData */ *#dXW\8qu
public CountBean() {} pOGVD
public void setCountType(String countTypes){ Y
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this.countType=countTypes; i%v^Zg&FU
} R&=Y7MfZ
public void setCountId(int countIds){ '<$(*
this.countId=countIds; N2xgyKy~
} 7@|(z:uw
public String getCountType(){ 6^}GXfJAc
return countType; e,|"9OK
} ^cBA8 1
public int getCountId(){ xw]Zo<F
return countId; w,9$*=k
} .\LWV=B
} [m!$01=
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CountCache.java }=;N3Q" #y
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/* 5H;* Nj@
* CountCache.java jHTaG%oh
* Y#3m|b45n
* Created on 2007年1月1日, 下午5:01 I?Eh
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* 5|wQeosXxI
* To change this template, choose Tools | Options and locate the template under XOVZ'V
* the Source Creation and Management node. Right-click the template and choose J(g!>Sp!p
* Open. You can then make changes to the template in the Source Editor. axonqSf
*/ }a|SgI
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package com.tot.count; noGMfZ1
import java.util.*; E^T/Qu
/** U/wY;7{)#
* Q(E$;@
* @author [}}oHm3&
*/ \D>'
public class CountCache { V=QvwQlZ
public static LinkedList list=new LinkedList(); @N1ta-D#
/** Creates a new instance of CountCache */ j+PW9>Uh
public CountCache() {} `:?padZG
public static void add(CountBean cb){ fh:=ja?bM3
if(cb!=null){ X
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list.add(cb); `p*7MZ9-
} mWta B>f
} hFs0qPVY
} DV]Kd
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CountControl.java M\>y&'J-
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/* ~)Ny8Dh
* CountThread.java OCY7Bls4
* XZJ }nXy
* Created on 2007年1月1日, 下午4:57 /$]dVvhX%
* pcoJ\&&W
* To change this template, choose Tools | Options and locate the template under /QD}_lh;,
* the Source Creation and Management node. Right-click the template and choose 0 l
G\QT
* Open. You can then make changes to the template in the Source Editor. ^kt#[N
*/ 6@; w%Ea
73 Tg{~
package com.tot.count; O/iew3YF
import tot.db.DBUtils; Xj?j1R>GB
import java.sql.*; %pe7[/
/** nNq| v=L
* ?)5}v4b
* @author 6(<AuhFu
*/ C
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public class CountControl{ IgR_p7['.
private static long lastExecuteTime=0;//上次更新时间 h&;\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {- 7T\mj
/** Creates a new instance of CountThread */ -Y2h vC
public CountControl() {} C Vyq/X
public synchronized void executeUpdate(){ \[+ZKj:
Connection conn=null; \Vr(P>
PreparedStatement ps=null; ib;:*
try{ J$]d%p_I
conn = DBUtils.getConnection(); O9:vPbn
conn.setAutoCommit(false); !N?|[n1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \CX`PZ><
for(int i=0;i<CountCache.list.size();i++){ a~:'OW:Q
CountBean cb=(CountBean)CountCache.list.getFirst(); \7jcZ~FBX%
CountCache.list.removeFirst(); [[LCEw
ps.setInt(1, cb.getCountId()); 9Z6O{
>
ps.executeUpdate();⑴ GriL< =?t
//ps.addBatch();⑵ (B7M*e
} f\2'/g}6a
//int [] counts = ps.executeBatch();⑶ - "h
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conn.commit(); zA\DI]:+
}catch(Exception e){ mVP@c&1w?
e.printStackTrace(); ){icI<
} finally{ +Y'(,J
try{ !H~G_?Mf\O
if(ps!=null) { "Do9gW
ps.clearParameters(); DLJu%5F
ps.close(); ,.x1+9X
ps=null; kYmkKl_
} bUU_NqUf*3
}catch(SQLException e){} N=)N
DBUtils.closeConnection(conn); eiJ $}\qJL
} _u]Wr%D@
} !C&}e8M|eX
public long getLast(){ SI4M<'fK
return lastExecuteTime; EX|Wd|aK
} {[NBTT9&
public void run(){ mst-:F[h
long now = System.currentTimeMillis(); n;/yo~RR
if ((now - lastExecuteTime) > executeSep) { FJ}/g
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//System.out.print("lastExecuteTime:"+lastExecuteTime); s{'r'`z.
//System.out.print(" now:"+now+"\n"); `>g:
:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); u4rG e!
lastExecuteTime=now; A@f`g[q
executeUpdate(); u\Tq5PYXt
} [8l8m6
else{ Bd31>
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); doW_vu
} 5O]ph[7
} at/bes W
} I[c/)
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 T%VC$u4F
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类写好了,下面是在JSP中如下调用。 qI5_@[S*
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<% 8%U+y0j6b
CountBean cb=new CountBean(); PL%U
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); FI Io{ru
CountCache.add(cb); [(F.x6z)
out.print(CountCache.list.size()+"<br>"); mC8c`#1T
CountControl c=new CountControl(); XSpX6fq
c.run(); d+\o>x|Y!Y
out.print(CountCache.list.size()+"<br>"); ApG_Gd.
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