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: K=h9Ce
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CountBean.java SsDmoEeB[
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/* agDM~= #F
* CountData.java *H2r@)Y[~
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* Created on 2007年1月1日, 下午4:44 k)=s>&hl
* 3ym',q
* To change this template, choose Tools | Options and locate the template under 9-a0 :bP
* the Source Creation and Management node. Right-click the template and choose '$(^W@M#6
* Open. You can then make changes to the template in the Source Editor. #'szP\
*/ ~-Qw.EdC
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package com.tot.count; CXMLt
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/** ZG8DIV\D7
* plstZ,#j
* @author 08\,<9
*/ KBc1{adDx@
public class CountBean { )g%d:xI
private String countType; `e&Suyf4B
int countId; FGmb<z 2p
/** Creates a new instance of CountData */ <=/hil
public CountBean() {} L^?qOylu
public void setCountType(String countTypes){ +lcbi
this.countType=countTypes; 4p;`C
} :J&oX
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public void setCountId(int countIds){ Ka
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this.countId=countIds; #f]SK[nR
} s-Tv8goNV
public String getCountType(){ ={&j07,*a
return countType; H40p86@M
} XK@E;Rv
public int getCountId(){ HBXOjr<,{
return countId; 3;{kJQ
} flbd0NB
} ;$wVu|&
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CountCache.java bJTBjS-7
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/* z$. 88^
* CountCache.java K
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* Created on 2007年1月1日, 下午5:01 c-6?2\]j@
* =X:Y,?
* To change this template, choose Tools | Options and locate the template under E*K;H8}s
* 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. =-n}[Y}A
*/ Y.rsR6
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package com.tot.count; M!^az[[
import java.util.*; [waIi3Dv\
/** 4vB<fPN
* Eo]xNn/g
* @author ( ^Nz9{
*/ VuZuS6~#J
public class CountCache { y766;
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public static LinkedList list=new LinkedList(); ]Q)OL
/** Creates a new instance of CountCache */ v`Oc,
public CountCache() {} -k e's
public static void add(CountBean cb){ z<XtS[ki
if(cb!=null){ c4eBt))}V
list.add(cb); tl^9WG
} $B5aje}i
} J}K$(;:
} A#iV=76_
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CountControl.java sS'm!7*(3
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/* [5Mr@f4I
* CountThread.java
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* B*Dz{a^.:
* Created on 2007年1月1日, 下午4:57 ~dTrf>R8M
* z5*'{t)
* To change this template, choose Tools | Options and locate the template under YO}<Ytx
* the Source Creation and Management node. Right-click the template and choose 6A+nS=
* Open. You can then make changes to the template in the Source Editor. Ne1$ee.NE
*/
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package com.tot.count; u>a5GkG.
import tot.db.DBUtils; &Hs!:43E-<
import java.sql.*; Yufc{M00
/** 59;KQ
* V/9!K%y
* @author d)Y}>@:W
*/ \bvfEP
public class CountControl{ |[b{)s?x
private static long lastExecuteTime=0;//上次更新时间 5vnrA'BhBU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p947w,1![
/** Creates a new instance of CountThread */ e^1Twz3z
public CountControl() {} &`2)V;t
public synchronized void executeUpdate(){ m#\dSl}
Connection conn=null; R.yvjPwJ
PreparedStatement ps=null; :P0mx
try{ z9Rp`z&`E
conn = DBUtils.getConnection(); )bscBj@
conn.setAutoCommit(false); v"Es*-{B
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $*=<Yw4
for(int i=0;i<CountCache.list.size();i++){ <frutU16\
CountBean cb=(CountBean)CountCache.list.getFirst(); 4~Q/"hMSkO
CountCache.list.removeFirst(); L)
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ps.setInt(1, cb.getCountId()); St*h>V6
ps.executeUpdate();⑴ ~oY^;/ j
//ps.addBatch();⑵ Z4
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} sD#.Oq4&]y
//int [] counts = ps.executeBatch();⑶ VRB;$
conn.commit(); pIqeXY
}catch(Exception e){ Q*~]h;6\{d
e.printStackTrace(); *VT/
} finally{ </*6wpN
try{ I9ep`X6Y
if(ps!=null) { &0JI!bR(
ps.clearParameters(); V1M.JU
ps.close(); 7J<5f)
ps=null; hkQ"OsU
} C e$w8z
}catch(SQLException e){} ;u)I\3`*!
DBUtils.closeConnection(conn); Jdj4\ju
} g]0_5?i
} *gWwALGo5
public long getLast(){ wI/iuc
return lastExecuteTime; YNi.SXH
} G" "ZI$`
public void run(){ #AQV(;r7@
long now = System.currentTimeMillis(); g3y+&Y_
if ((now - lastExecuteTime) > executeSep) { P/_['7
//System.out.print("lastExecuteTime:"+lastExecuteTime); o?\?@H
//System.out.print(" now:"+now+"\n"); 1iF1GkLEq
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); TOQP'/
lastExecuteTime=now; /mzlH
executeUpdate(); <wD-qT W
} 3(80:@|
else{ |&i<bqLw:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d/~9&wLSb
} }@d @3
} 13x p_j
} /cP"h!P}~~
//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%n-[ZL
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类写好了,下面是在JSP中如下调用。 ey$&;1x#5
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<% |P?*5xPB
CountBean cb=new CountBean(); s!$a\ k
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 63IM]J
CountCache.add(cb); S3Jo>jXS "
out.print(CountCache.list.size()+"<br>"); Wmv#:U
CountControl c=new CountControl(); J5,9_uo]
c.run(); DZtsy!xA
out.print(CountCache.list.size()+"<br>"); F*ylnB3z
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