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: *iSE)[W
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CountBean.java 4jVd
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/* {XnBj}C
* CountData.java <#./q LSR
* 3CSwcD
* Created on 2007年1月1日, 下午4:44 A(+V{1L'
* \~C/
* To change this template, choose Tools | Options and locate the template under Ga
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* the Source Creation and Management node. Right-click the template and choose ;hd%wmE
* Open. You can then make changes to the template in the Source Editor. !xU\s'I+#
*/ #=F{G4d)!=
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package com.tot.count; uy|]@|J
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/** !G'wC0
* btDTC9O
* @author Izfq`zS+\s
*/ O4^' H}*
public class CountBean { b:
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private String countType; )[E7\pc
int countId; ftV~!r
/** Creates a new instance of CountData */ @,]$FBT"5
public CountBean() {} <yw=+hz[u
public void setCountType(String countTypes){ &5%~Qw..
this.countType=countTypes; T I yHM1+
} FaaxfcIfkw
public void setCountId(int countIds){ 5E${
this.countId=countIds; %^u
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} K8v@)
public String getCountType(){ a,xy38T<
return countType; aMxM3"
} w:~vfdJ
public int getCountId(){ Ou|kb61zg
return countId; H[?l)nZ}
} anH ]]
}
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CountCache.java "(p&Oz
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/* B2)5Z]
* CountCache.java j:2*hF!E
* l%
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* Created on 2007年1月1日, 下午5:01 7lzmAih
* @Fb
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* To change this template, choose Tools | Options and locate the template under zRm@ |IT
* the Source Creation and Management node. Right-click the template and choose }%3i8e
* Open. You can then make changes to the template in the Source Editor. tYhNr
*/ :M@#.
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package com.tot.count; byk9"QeY\
import java.util.*; Se!B,'C%
/** jGDuKb@:
* T^2o'_:
* @author q9nQ/]rkHF
*/ {t('`z
public class CountCache { 85:mh\@-G
public static LinkedList list=new LinkedList(); -Y>QKS
/** Creates a new instance of CountCache */ 'lgS;ItpKu
public CountCache() {} #*"I?B/fd8
public static void add(CountBean cb){ .ITTY QHv)
if(cb!=null){ f Qf5%
list.add(cb); 2KNs,4X@
} o"qG'\x
} 6'.CW4L
} yk2XfY
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CountControl.java \IOF 9)F
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/* jf=90eJc
* CountThread.java sGGi7%
* )kE1g&
* Created on 2007年1月1日, 下午4:57 *nHkK!d<N
* ~[0^{$rrWs
* To change this template, choose Tools | Options and locate the template under n?v$C:jLN
* the Source Creation and Management node. Right-click the template and choose zy8D&7Ytf
* Open. You can then make changes to the template in the Source Editor. N1dM,H
*/ E$4Ik.k
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package com.tot.count; YcM0A~<
import tot.db.DBUtils; p<Vj<6.=?
import java.sql.*; y6>fK@K~
/** V"A*B
* J+qcA}
* @author 9lqD~H.
*/ Y>CZ
public class CountControl{ /)V8X#,
private static long lastExecuteTime=0;//上次更新时间 2))pB/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Rab7Y,AA
/** Creates a new instance of CountThread */ MVp+2@)}s
public CountControl() {} F441K,I
public synchronized void executeUpdate(){ odTIz{9qG
Connection conn=null; N{K[sXCW
PreparedStatement ps=null; B~u`bn,iQ
try{ jjg[v""3|
conn = DBUtils.getConnection(); r@G34QC+
conn.setAutoCommit(false); 4z^VwKH\ j
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); fczH^+mI
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); gzp]hh@4
CountCache.list.removeFirst(); GAlM:>
ps.setInt(1, cb.getCountId()); Az6tu <
ps.executeUpdate();⑴ ohPDknHp
//ps.addBatch();⑵ bO
}9/Ay
} W;.LN<bx
//int [] counts = ps.executeBatch();⑶ q]gF[&QZ
conn.commit(); er2# h
}catch(Exception e){ ifadnl26
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e.printStackTrace(); >2#F5c67
} finally{ v<gve<]
try{ BBj>ML\X
if(ps!=null) { 69zMWuY
ps.clearParameters(); w[/m:R?eX
ps.close(); ^dKtUH/78G
ps=null; +wm%`N;v<
} }IV=qW,
}catch(SQLException e){} AL[,&_&uV
DBUtils.closeConnection(conn); -\8v{ry
} [f`7+RHrd
} ;_A?Zl}
public long getLast(){ 'I@l$H
return lastExecuteTime; o AM)<#U>
} P"Y7N?\](
public void run(){ D3C3_
@*
long now = System.currentTimeMillis(); R(#ZaFuo[
if ((now - lastExecuteTime) > executeSep) { gLWbd~
//System.out.print("lastExecuteTime:"+lastExecuteTime); pUeok+k_
//System.out.print(" now:"+now+"\n"); gO_d!x*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); )8V=!73
lastExecuteTime=now; G4J)o?:m@
executeUpdate(); uVzvUz{b
} mfr7w+DK
else{ ,xy$h }g
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .\"8H1I\T
} ?PU7xO;_
} byX)4&
} e0`5PVJ
//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 &>vfm9
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类写好了,下面是在JSP中如下调用。 \T^ptj(0
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<% f
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CountBean cb=new CountBean(); T!t9`I0Zz
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dEPLkv
CountCache.add(cb); x+W,P
out.print(CountCache.list.size()+"<br>"); ^8
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CountControl c=new CountControl(); ulNMqz\.
c.run(); kB_T9$0e#
out.print(CountCache.list.size()+"<br>"); =$\9t $A
%>