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: MObt,[^W
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CountBean.java C*U'~qRK
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/* Tus}\0/i>
* CountData.java 1c3TN#|)W
* M;cO0UIwO
* Created on 2007年1月1日, 下午4:44 )vmA^nU>
*
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* To change this template, choose Tools | Options and locate the template under T2}FYVj?!g
* the Source Creation and Management node. Right-click the template and choose =U8a ?0
* Open. You can then make changes to the template in the Source Editor. Q~R
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*/ 'O5'i\uz
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package com.tot.count; 4h5g'!9-g
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/** hjaT^(Y
* ]k9)G*
* @author ,Y3W?
*/ (P&4d~)m
public class CountBean { -':Y\:W
private String countType; uwRr LF
int countId; ~m|Mg9-
/** Creates a new instance of CountData */ 4}`
public CountBean() {} [V4 {c@
public void setCountType(String countTypes){ /R>nr"
this.countType=countTypes; 'n<iU st
} Q{k
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public void setCountId(int countIds){ pO8ePc@=D
this.countId=countIds; [((;+B
} -(O-%
public String getCountType(){ LL|7rS|o
return countType; WL` 9~S
} d
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public int getCountId(){ Vy_2 .
return countId; sXd8rj:o
} :4^\3~i1X
} e/->_T(I
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CountCache.java Cy*|&=>j
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/* {.yStB.T
* CountCache.java ,gL9?Wz
* ?$e9<lsQq)
* Created on 2007年1月1日, 下午5:01 *^([ ~[
* N}\[Gr
* To change this template, choose Tools | Options and locate the template under 9;?UvOI;
* the Source Creation and Management node. Right-click the template and choose }K8/-d6
* Open. You can then make changes to the template in the Source Editor. 88c<:fK
*/ 1SrJ6W @j[
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package com.tot.count; U^qt6$bK
import java.util.*; >DPB!XA3
/** Hcc"b0>}{
* H3Se={5h\A
* @author V138d?Mm
*/ }E`dZW*!!
public class CountCache { LN_xq&.
public static LinkedList list=new LinkedList(); z5W@`=D
/** Creates a new instance of CountCache */ iD= p\
public CountCache() {} %F kMv
public static void add(CountBean cb){ Fu^^i&
if(cb!=null){ `bc;]@"
list.add(cb); E9V5$
} (%O@r!{
} 3pmWDG6L
} sBV4)xM
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CountControl.java =TqQbadp
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/* D5~n/.B"
* CountThread.java hK<5KZ/4
* w1UA?+43
* Created on 2007年1月1日, 下午4:57 ~q&pF"va8
* !ZU2{
* To change this template, choose Tools | Options and locate the template under G<M:Ak+~
* the Source Creation and Management node. Right-click the template and choose tl'n->G>v
* Open. You can then make changes to the template in the Source Editor. 0j C3fT!n
*/ Jjl`_X$CB
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package com.tot.count; fr!Pj(Q1
import tot.db.DBUtils; f@co<iA
import java.sql.*; y,pZTlE
/** }-~T<egF
* uytE^
* @author lD mtQk-SN
*/ k<+0o))
public class CountControl{ l|5fE1K9U
private static long lastExecuteTime=0;//上次更新时间 @|'5n
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 mw5?[@G-
/** Creates a new instance of CountThread */ >[6{LAe~hp
public CountControl() {} /pp1~r.s?>
public synchronized void executeUpdate(){ ~ H6r.:]
Connection conn=null; ;O<9|?
PreparedStatement ps=null; 6ksAc%|5
try{ ^9-&o
conn = DBUtils.getConnection(); ^T~gEv
conn.setAutoCommit(false); ](F#`zUQ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /k"`7`!
for(int i=0;i<CountCache.list.size();i++){ MQ)L:R`L
CountBean cb=(CountBean)CountCache.list.getFirst(); dJ?XPo"Cm=
CountCache.list.removeFirst(); `mT$s,:h
ps.setInt(1, cb.getCountId()); 7H>@iI"?
ps.executeUpdate();⑴ OCy0#aPRS
//ps.addBatch();⑵ fm~kM
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} KgN)JD>
//int [] counts = ps.executeBatch();⑶ wM_c48|d
conn.commit(); fIGFHZy,
}catch(Exception e){ 2DD:~Tbi
e.printStackTrace(); Dup;e&9g
} finally{ fSDi-I
try{ 7w;O}axI
if(ps!=null) { 76.{0c
ps.clearParameters(); 5PcJZi^.l
ps.close(); 4.RG4Jq
ps=null; =uDgzdDyE
} )bx_;9Y{
}catch(SQLException e){} _tr<}PnZ
DBUtils.closeConnection(conn); 6WoAs)ZF
} L !4t[hhe=
} E2L(wt}^
public long getLast(){ Z>)][pL
return lastExecuteTime; fFjH "2WD
} ;v
public void run(){ . |*f!w}5
long now = System.currentTimeMillis(); #}^-C&~
if ((now - lastExecuteTime) > executeSep) { ``ekR6[ 8c
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7kKy\W
//System.out.print(" now:"+now+"\n"); 4(l?uU$
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); vILy>QS)
lastExecuteTime=now; S]sk7
executeUpdate(); N)% ;jh:T
} 97!>%d[0
else{ midsnG+jnf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); d7Ur$K\=y
} FI8Oz,
} A~nf#(!^]
} \8OO)98'
//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@v&s
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类写好了,下面是在JSP中如下调用。 }Vu\(~
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<% {5*|C-WWtG
CountBean cb=new CountBean(); *sQcg8{^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nxQ?bk}*d
CountCache.add(cb); 6{d6s#|%
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); 6pE :A@
c.run(); EPW7+Ve
out.print(CountCache.list.size()+"<br>"); `nR %Cav,U
%>