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: 1z8"Gk6
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CountBean.java m}wn+R
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/* Q
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* CountData.java D8wf`RUt
* W]oD(eZ
* Created on 2007年1月1日, 下午4:44 z)^|.
* 2/*u$~
* To change this template, choose Tools | Options and locate the template under xc#t8`
* the Source Creation and Management node. Right-click the template and choose N x&/p$d
* Open. You can then make changes to the template in the Source Editor. ~|}]
*/ B[@q.n
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package com.tot.count; %LMpErZO
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/** R|C`
* tr<fii3<
* @author `HRL .uX
*/ e%JIqKS
public class CountBean { h+1|.d
private String countType; skcyLIb
int countId; `MSig)V
/** Creates a new instance of CountData */ M4C8K{}
public CountBean() {} @vlP)"
public void setCountType(String countTypes){ 5j`xSG
this.countType=countTypes; <}RI<96
} n>ui'}L
public void setCountId(int countIds){ TF/NA\0c$
this.countId=countIds; U*r54AyP
} }pMVl
public String getCountType(){ VC88re`
return countType; $z%(He
} <t"T'\3
public int getCountId(){ V6][*.i!9
return countId; [;z\bV<S
} V8M()7uJ
} Qfm$q~`D^W
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CountCache.java w{W+WJ
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/* A O:F*%Q u
* CountCache.java L\2"1%8Wj
* H[~ D]RG}'
* Created on 2007年1月1日, 下午5:01 "#O9ij
* @Ul3J )=m
* To change this template, choose Tools | Options and locate the template under MQ!4"E5"j
* the Source Creation and Management node. Right-click the template and choose 6j|Ncv
* Open. You can then make changes to the template in the Source Editor. 05LkLB
*/ n=<c_a)Nb
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package com.tot.count; U80=f2
import java.util.*; ,j*9 )
/** 1VgGF^cYR
* WEj{2+
* @author J 4gtm"2)
*/ xQFY/Z
public class CountCache { {1SsHir>
public static LinkedList list=new LinkedList(); "bhK%N;
/** Creates a new instance of CountCache */ .2E/(VM
public CountCache() {} 0zH-g
public static void add(CountBean cb){ R2Tt6
if(cb!=null){ -MTk9<qnT
list.add(cb); #"UO`2~`l
} d0 )725Ia
} w6V/Xp][U
} nc;eNB
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CountControl.java |jiIx5qr
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/* _Xd"'cXw
* CountThread.java (.:*GUg
* A] |w1nq
* Created on 2007年1月1日, 下午4:57 O-V|= t
* a}%f+`z
* To change this template, choose Tools | Options and locate the template under sq2:yt
* the Source Creation and Management node. Right-click the template and choose \\dUp>1=
* Open. You can then make changes to the template in the Source Editor. `7=$I~`
*/ AmF[#)90P
]<^2B?}
package com.tot.count; <r#FI8P;X
import tot.db.DBUtils; _2jL]mB
import java.sql.*; PB@IPnB-
/** Q6HJ+H-Ub
* N\PdX$
* @author "/zgh
*/ b{<?E };%
public class CountControl{ YCDH 0M
private static long lastExecuteTime=0;//上次更新时间 ZHNL~=r}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |P>7C
/** Creates a new instance of CountThread */ #sw4)*v
public CountControl() {} T<B}Z11R
public synchronized void executeUpdate(){ 4QA~@pBX^{
Connection conn=null; !_W/p`Tc
PreparedStatement ps=null; s/7Z.\
try{ *tUOTA 3L
conn = DBUtils.getConnection(); J#$U<`j*G
conn.setAutoCommit(false); ^bv^&V&IB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); q-`&C
for(int i=0;i<CountCache.list.size();i++){ O t)}:oG
CountBean cb=(CountBean)CountCache.list.getFirst(); &4:R(]|
CountCache.list.removeFirst(); M(a%Qk?]/
ps.setInt(1, cb.getCountId()); 3mHzOs\jU
ps.executeUpdate();⑴ lOt7ij(,L
//ps.addBatch();⑵ e-rlk5k%f
} J%CCUl2
//int [] counts = ps.executeBatch();⑶ g!XC5*}
conn.commit(); INA3^p'w
}catch(Exception e){ =@!t/LR7kg
e.printStackTrace(); ;stjqTd
} finally{ hW#^H5?
try{ LI%dJ*-V
if(ps!=null) { t5+p]7
ps.clearParameters(); Y1h)aQ5{
ps.close(); ^VXhv9\>B
ps=null; 6k
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} zFjz%:0
}catch(SQLException e){} ii?T:T@
DBUtils.closeConnection(conn); @5^&&4>N
} ^)-[g
} w-n}&f
public long getLast(){ <MbhBIejr
return lastExecuteTime; +4:eb)e
} e#*3X4<\K
public void run(){ (xb2H~WrN
long now = System.currentTimeMillis(); _f^6F<!
if ((now - lastExecuteTime) > executeSep) { lEHx/#qt9
//System.out.print("lastExecuteTime:"+lastExecuteTime); iAz0 A
//System.out.print(" now:"+now+"\n"); fmixWL7.Zg
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?h[HC"V/2
lastExecuteTime=now; EnWv9I<
executeUpdate(); )95k3xo
} m#'eDO:
else{ UQu6JkbLL
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :(A&8<}-6
} q}Q G<%VR
} G!Brt&_'
} G=zNZ
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 vclc%ws
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-#
类写好了,下面是在JSP中如下调用。 b&P)J|Fe
JQQ[jl;
<% ,'0#q
CountBean cb=new CountBean(); I;w!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B$g\;$G
CountCache.add(cb); -FJ3;fP&
out.print(CountCache.list.size()+"<br>"); 8m{e,o2.
CountControl c=new CountControl(); ;}E}N:A
c.run(); \ivxi<SR
out.print(CountCache.list.size()+"<br>"); 'V?FeWp
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