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: QW}N,j$
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CountBean.java '${xZrzmt
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/* ^T/d34A;SP
* CountData.java w#`E;fN'
*
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* Created on 2007年1月1日, 下午4:44 IH'&W
* FFqqAT5
* To change this template, choose Tools | Options and locate the template under \*$''`b)j
* the Source Creation and Management node. Right-click the template and choose #+Cu&l
* Open. You can then make changes to the template in the Source Editor. ,Tc598D
*/ dJd(m&.|N
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package com.tot.count; xD<:'-ri>
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/** D[ (A`!)
* +&hd3
* @author bIahjxd:
*/ _kT$/k
public class CountBean { E
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private String countType; k9?fE
int countId; D>Dch0{H,:
/** Creates a new instance of CountData */ 'uw=)8t7
public CountBean() {} 8!{F6DG
public void setCountType(String countTypes){ $17utJ58
this.countType=countTypes; J(\f(jh/
} elf2!
public void setCountId(int countIds){ F&x9.
this.countId=countIds; %B'*eBj~fw
} -5t.1/
public String getCountType(){ DkGC+Dw
return countType; %JC-%TRWK
} %$L!N-U6
public int getCountId(){ d@-bt s&3
return countId; xA>O4SD
} h*9s^`9)
} V/}g'_E
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CountCache.java fB3W} dr
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/* !B &%!06
* CountCache.java B'Ll\<mq@
* +
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* Created on 2007年1月1日, 下午5:01 }?jL;CCe
* R3SAt-IE
* To change this template, choose Tools | Options and locate the template under 8Yq_6
* the Source Creation and Management node. Right-click the template and choose o3~ecJ?k
* Open. You can then make changes to the template in the Source Editor. O_jf)N\pi
*/ Lx:O Dd
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package com.tot.count; c~a:i=y67
import java.util.*; !yQ# E2/A
/** A\7qPfpG
* MjW g
* @author 8QN#PaY
*/ =)GhrWeVi4
public class CountCache { $($26g
public static LinkedList list=new LinkedList(); 3;6Criq}
/** Creates a new instance of CountCache */ pO.+hy
public CountCache() {} s*k[Fbi
public static void add(CountBean cb){ 9$pQ|e0tJ
if(cb!=null){ HTz&h#)JQ
list.add(cb); 5[_|+
} '% $)"g]/#
} CG(G){u&
} l|c#
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CountControl.java *uq;O*s
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/* pLvvv#Y
* CountThread.java `|\z#Et
* ;LM,<QJ
* Created on 2007年1月1日, 下午4:57 7LM?<lp]
* HH+$rrTT
* To change this template, choose Tools | Options and locate the template under ?,J'3nZ'
* the Source Creation and Management node. Right-click the template and choose CVp`G"W:
* Open. You can then make changes to the template in the Source Editor. 8MH ZWi
*/ K(+ ~#$|-~
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package com.tot.count; l H@hV
import tot.db.DBUtils; J~3+j6?%
import java.sql.*; 6 ZutU ~HS
/** /K{`gc
* FCu0)\
* @author )!:}R}q
*/ 7n,*3;I
public class CountControl{ Vnu*+
private static long lastExecuteTime=0;//上次更新时间 #3l&N4/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 j~d<n_
/** Creates a new instance of CountThread */ jU~
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public CountControl() {} y3 vDKZ
public synchronized void executeUpdate(){ Ydw04WEJ
Connection conn=null; _<`j?$P
PreparedStatement ps=null; t7"vAjZU
try{ Uk=-A
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conn = DBUtils.getConnection(); f,'gQ5\ X3
conn.setAutoCommit(false); brk>oM;t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); XANPI|
for(int i=0;i<CountCache.list.size();i++){ 2nL[P#r
CountBean cb=(CountBean)CountCache.list.getFirst(); .]_
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CountCache.list.removeFirst(); |]tIE{d
ps.setInt(1, cb.getCountId()); FOA y'76p
ps.executeUpdate();⑴ VfK8')IXk
//ps.addBatch();⑵ DeTx7 i0
} xWv@PqXD
//int [] counts = ps.executeBatch();⑶ WQ(*A
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conn.commit(); dvWQ?1l_
}catch(Exception e){ T(UPWsj
e.printStackTrace(); &\Es\qVSf
} finally{ &R\t<X9 n
try{ UQmdm$.
if(ps!=null) { bT^6AtsJ
ps.clearParameters(); b'1n1L
ps.close(); sOegR5?;
ps=null; h JVy-]
} ^h}xFiAV#
}catch(SQLException e){} bG`aF*10)!
DBUtils.closeConnection(conn); dWhki|c
} s}NE[Tw
} FwB}@)3
public long getLast(){ /0PBY-O
return lastExecuteTime; .d)X.cO
} RqV* O}Am
public void run(){ j:)"s_
long now = System.currentTimeMillis(); [YbnpI
if ((now - lastExecuteTime) > executeSep) { |~'PEY
//System.out.print("lastExecuteTime:"+lastExecuteTime); R/&Ev$:
//System.out.print(" now:"+now+"\n"); ]!JUiFj"uD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); K"%_q$[YQ
lastExecuteTime=now; 'P1I-ue
executeUpdate(); yMdE[/+3
} h[|c?\E
z
else{ q2o`.f+I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2$)xpET
} |yqL0x0\l
} jea{BhdUr
} I\%a<
//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 S?ypka"L
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类写好了,下面是在JSP中如下调用。 ;7jszs.6%
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<% '<}N`PS#N
CountBean cb=new CountBean(); ia'eV10
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); fwe4f
CountCache.add(cb); F/91Es
out.print(CountCache.list.size()+"<br>"); R^DZ@[\iV
CountControl c=new CountControl(); )=KD
c.run(); 0X.(BRI~6p
out.print(CountCache.list.size()+"<br>"); eXB'>#&s
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