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: FG6h,7+
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CountBean.java C<NLE-
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/* bSiYHRH.e
* CountData.java ^A!Qc=#z}
* Id_2PkIN$~
* Created on 2007年1月1日, 下午4:44 1,6}_MA
* ^Y=\#-Dd
* To change this template, choose Tools | Options and locate the template under hlV=qfc
* the Source Creation and Management node. Right-click the template and choose T ?$:'XJ
* Open. You can then make changes to the template in the Source Editor. 8B/\U'
*/ C>-aIz!y
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package com.tot.count; ~<O7$~
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/** `7[EKOJ3g
* @LS@cCC,a
* @author 3N dq>
*/ tQ8.f
public class CountBean { '?!zG{x
private String countType; B|R@5mjm
int countId; =:&ly'QB&
/** Creates a new instance of CountData */ +b.g$CRr
public CountBean() {} ukIQr/k
public void setCountType(String countTypes){ >OL 3H$F
this.countType=countTypes; -7*ET3NSI/
} SO IHePmwK
public void setCountId(int countIds){ W{5#@_pL
this.countId=countIds; le1}0L
} )Hpa}FGT
public String getCountType(){ x,rlrxI
return countType; QIB\AAclO
} qCljo5Tq'
public int getCountId(){ tZ'|DCT
return countId; <L"GqNuRQ
} A;*d}Xe&J
} { &"CH]r
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CountCache.java I$<<(VWH
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/* 8dO!
* CountCache.java +?:7O=Y
* *QwY]j%^
* Created on 2007年1月1日, 下午5:01 }])oM|fgO
* O!P H&;H
* To change this template, choose Tools | Options and locate the template under L W[9
* the Source Creation and Management node. Right-click the template and choose vd[}Gd
* Open. You can then make changes to the template in the Source Editor. jF0jkj1&/[
*/
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package com.tot.count; [U5\bX@$
import java.util.*; eO?p*"p" F
/** s$cK(S#
* h-G)o[MA
* @author #:[t^}
*/ Tw""}|] g
public class CountCache { V!lZ\)
public static LinkedList list=new LinkedList(); 1DE1.1
/** Creates a new instance of CountCache */ pi
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public CountCache() {} Yzh"1|O
public static void add(CountBean cb){ @)|C/oA
if(cb!=null){ ^Pbk#|$rU
list.add(cb); Y8m1M-#w
} J%x\=Sv
} umiBj)r
} *M:B\D
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CountControl.java hWD;jR
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/* 77\]B
* CountThread.java RloK,bg
* 3~uW I%I`
* Created on 2007年1月1日, 下午4:57 -I&m:A$4*
* ~/98Id}v
* To change this template, choose Tools | Options and locate the template under v2B0q4*BS?
* the Source Creation and Management node. Right-click the template and choose RxI(:i?
* Open. You can then make changes to the template in the Source Editor. $npT[~U5
*/ !HnXXVW
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package com.tot.count; f33 l$pOp
import tot.db.DBUtils; L&u$t}~)
import java.sql.*; >'&p>Ad)
/** I@yCTluV$
* xx#zN0I>-y
* @author ,N!o
*/ orWbU
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public class CountControl{ _V7r1fY:
private static long lastExecuteTime=0;//上次更新时间 {bJ`~b9e
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 FB{KH .
/** Creates a new instance of CountThread */ OmIg<v0\;
public CountControl() {} whi`Z:~
public synchronized void executeUpdate(){ uBNn6j
Connection conn=null; LUM@#3&
PreparedStatement ps=null; -uMSe~
try{ EfCx`3~EX
conn = DBUtils.getConnection(); D-5VC9{
conn.setAutoCommit(false); _j< K=){
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L"o>wYx
for(int i=0;i<CountCache.list.size();i++){ ??M"6k
CountBean cb=(CountBean)CountCache.list.getFirst(); =;2%a(
CountCache.list.removeFirst(); eHn7iuS8
ps.setInt(1, cb.getCountId()); ,
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ps.executeUpdate();⑴ gcdlT7F)b-
//ps.addBatch();⑵ y5*Z3"<
}
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//int [] counts = ps.executeBatch();⑶ JM x>][xD
conn.commit(); amOnqH-(
}catch(Exception e){ c'%-jG)\
e.printStackTrace(); `(_s|-$
} finally{ .Le?T&_
try{ /OLFcxEWh
if(ps!=null) { [AYOYENp-
ps.clearParameters(); '8!YD?n
ps.close(); F'4w;-ax
ps=null; 5=v}W:^v.
} x4;"!Kq\
}catch(SQLException e){} ;<Ar=?
DBUtils.closeConnection(conn); fI{&#~f4C
} x:),P-~w
} r:f[mk"-"A
public long getLast(){ pWK(z[D
return lastExecuteTime; `6lr4Kk @R
} ts\5uiB<%
public void run(){ >7I15U
long now = System.currentTimeMillis(); gy#/D& N[
if ((now - lastExecuteTime) > executeSep) { +
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//System.out.print("lastExecuteTime:"+lastExecuteTime); e1%/26\
//System.out.print(" now:"+now+"\n"); g!lWu[d
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H`1{_
lastExecuteTime=now; N/%WsQp
executeUpdate(); xTj|dza
} Nl^;A><u
else{ 7"sD5N/>uh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); DI:]GED"=
} r^FhTzA=1
} -I8=T]_D
} ';3{T:I
//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 }4 )H
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类写好了,下面是在JSP中如下调用。 wSa)*]%
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<% ,K)_OVB
CountBean cb=new CountBean(); s/$?^qtyC
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); iiT"5`KY
CountCache.add(cb); lAb*fafQy
out.print(CountCache.list.size()+"<br>"); hIy ~B['
CountControl c=new CountControl(); 7gf05Z'=
c.run(); jrr EAp
out.print(CountCache.list.size()+"<br>"); F*IzQ(#HW
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