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: T[evh]koB
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CountBean.java 3*T/ 7\
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/* TNDp{!<|L;
* CountData.java -_xTs(;|8
* b")O#v.
* Created on 2007年1月1日, 下午4:44 9?q ^yy
* o5['5?i} /
* To change this template, choose Tools | Options and locate the template under L&KL]n
* the Source Creation and Management node. Right-click the template and choose p"7]zq]'
* Open. You can then make changes to the template in the Source Editor. <*I*#WI&B
*/ #
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package com.tot.count; vmv6y*qU
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/** Ng1bjq}E2
* >;]S+^dXY
* @author xU2i&il^!
*/ odDVdVx0
public class CountBean { ,k1ns?i9KH
private String countType; >7)QdaB
int countId; g:.LCF
/** Creates a new instance of CountData */ G5|'uKz2"
public CountBean() {} Adet5m.|[8
public void setCountType(String countTypes){ @HTs.4
this.countType=countTypes; lD'^6
} Z<W f/
public void setCountId(int countIds){ S'`G7ht
this.countId=countIds; WL|71?@C
} 0}YadNb7
public String getCountType(){ ]N,'3`&::
return countType; 0eKLp8;Lh
} U\W$^r,
public int getCountId(){ 1cx%+-
return countId; TD-B\ @_
} P)LQ=b}V#;
} wz@[rMf
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CountCache.java '"XVe+.O
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/* |z8_]o+|r1
* CountCache.java C8do8$
* eY%Ep=J
* Created on 2007年1月1日, 下午5:01 JvEW0-B^l,
* 3UF^Ff<wo
* To change this template, choose Tools | Options and locate the template under EuA352x
* the Source Creation and Management node. Right-click the template and choose RameaFX8
* Open. You can then make changes to the template in the Source Editor. Unansk
*/ $m-C6xC/
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package com.tot.count; K47.zu
import java.util.*; ,<C~DSAyZ
/** [vz2< genn
* ?)[=>Kp
* @author Sj:c {jyJd
*/ Hq~SRc~
public class CountCache { ?r*}1WsH
public static LinkedList list=new LinkedList(); 'R2*3<
/** Creates a new instance of CountCache */ =(~*8hJ
public CountCache() {} a^^OI|?
public static void add(CountBean cb){ {u0sbb(
if(cb!=null){ <WbO&;%
list.add(cb); S;/pm$?/
} !]9qQ7+R%
} yRDtPK"E-
} 6mIeV0Q'
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CountControl.java l^%52m@{
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/* Z2-tDp(I
* CountThread.java &_s^C?x
* 6(7dr?^eGT
* Created on 2007年1月1日, 下午4:57 ;mr*$Iu 7|
* r[^O 7
* To change this template, choose Tools | Options and locate the template under 8M,z#DF
* the Source Creation and Management node. Right-click the template and choose X{[$4\di{
* Open. You can then make changes to the template in the Source Editor. ug'^$geM
*/ 9
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package com.tot.count; dj4a)p|YN
import tot.db.DBUtils; @HE?G
import java.sql.*; BlM(Q/z
/** U]B-B+-
* ar S@l<79
* @author 3[?;s}61
*/ E$A=*-u
public class CountControl{ @7;}6,)
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 '*Tt$0#o
/** Creates a new instance of CountThread */ ynf!1!4
public CountControl() {} &OkPO|
public synchronized void executeUpdate(){ _PQk<QZ
Connection conn=null; <]_[o:nOP
PreparedStatement ps=null; ^rO!-
try{ }[PC
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conn = DBUtils.getConnection(); qP zxP @4
conn.setAutoCommit(false); jK%Lewq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (dx~lMI
for(int i=0;i<CountCache.list.size();i++){ @k# xr
CountBean cb=(CountBean)CountCache.list.getFirst(); T1 1>&K)
CountCache.list.removeFirst(); Q ~n%c7
ps.setInt(1, cb.getCountId()); 3hEbM'L
ps.executeUpdate();⑴ KdzV^6K<c
//ps.addBatch();⑵ >wFn|7\)s>
} 'c]Pm,Ls
//int [] counts = ps.executeBatch();⑶
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conn.commit(); ,|;\)tT
}catch(Exception e){ JuOCOl\
e.printStackTrace(); S\GxLW@x
} finally{ +D[C.is>]}
try{ 5`lVC$cP
if(ps!=null) { 0zsmZ]b5E
ps.clearParameters(); wbk$(P'gN
ps.close(); obv_?i1
ps=null; [@3.dd
} b`Jsu!?{
}catch(SQLException e){} W59 xe&l
DBUtils.closeConnection(conn); :QHh;TIG=<
} p;D
{?H/
} !/!Fc'A
public long getLast(){ E8wkqZN
return lastExecuteTime; L$"pk{'
} a]6dhQ`
public void run(){ >svx
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long now = System.currentTimeMillis(); 1zCgPiAem
if ((now - lastExecuteTime) > executeSep) { CHjm7
//System.out.print("lastExecuteTime:"+lastExecuteTime); ,w=u?
//System.out.print(" now:"+now+"\n"); 6\VZ6oS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); eOfVBF<C2
lastExecuteTime=now; J$T(p%
executeUpdate(); G,1g~h%I$
} }I#_H
else{ v-"nyy-&Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !kH 1|
} 0,8RA_Ca}
} C~nL3w
} {d)L0KXK
//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 10GU2a$0"$
=.):tGDp
类写好了,下面是在JSP中如下调用。 }^b
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<% 9C!b
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CountBean cb=new CountBean(); <^942y-=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9T1-{s
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CountCache.add(cb); 3;!!`R>e
out.print(CountCache.list.size()+"<br>"); MOi1+`kwh
CountControl c=new CountControl(); :2XX~|
c.run(); sv#b5,>9
out.print(CountCache.list.size()+"<br>"); F ^m;xy
%>