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: L]d-hs
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CountBean.java 8zA=;~GHP
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/* uL3Eq>~x
* CountData.java " R-!(9k^`
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* Created on 2007年1月1日, 下午4:44 ]UH`Pdlt
* Si_%Rr&jW
* To change this template, choose Tools | Options and locate the template under &VV~%jl;k
* the Source Creation and Management node. Right-click the template and choose ~zSCg|"r
* Open. You can then make changes to the template in the Source Editor. @+9<O0
*/ %^1cyk
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package com.tot.count; <Q?a=4
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/** bYi`R)
* YO}1(m
* @author wjh=Q
*/ _)]+hUwY
public class CountBean { N\HQN0d9
private String countType; tID%}Z v
int countId; &}?$i7x5
/** Creates a new instance of CountData */ ;5tazBy&:C
public CountBean() {} zo[[>MA
public void setCountType(String countTypes){ ^|/](
this.countType=countTypes; W?eu!wL#p
} } ~"hC3w
public void setCountId(int countIds){ x_c7R;C
this.countId=countIds; %I-+Ead0i
} $ &P>r
public String getCountType(){ [5uRS}!
return countType; A |3tI
} 8F:e|\SB#
public int getCountId(){ HcedE3Rg
return countId; 6_d.Yfbq
} wKi^C8Z2
}
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CountCache.java J?Dq>%+^
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/* *P 3V
* CountCache.java `ORECg)
* e"'#\tSG
* Created on 2007年1月1日, 下午5:01 zGc:
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* n+BJxu?
* To change this template, choose Tools | Options and locate the template under 3/b;7\M
* the Source Creation and Management node. Right-click the template and choose +,yK;^b
* Open. You can then make changes to the template in the Source Editor. zoDH` h_
*/ yuDZ~0]R
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package com.tot.count; {X*^s5{;H
import java.util.*; ;b`[&g
/** K
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* XuD=E
* @author rHf&:~
*/ + J{0 E
public class CountCache { <c%W")0
public static LinkedList list=new LinkedList(); Kh4$ wwn
/** Creates a new instance of CountCache */ +<}0|Xl&
public CountCache() {} NM0tp )h
public static void add(CountBean cb){ K{ \;2M
if(cb!=null){ `E!N9qI?t$
list.add(cb); <)\y#N
} 7lS#f1E
} p/2jh&
} 9_QP !,
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CountControl.java 2MATpV#BT
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/* {0;3W7
* CountThread.java iSFuT7;%
* m$9w"8R
* Created on 2007年1月1日, 下午4:57 f+|$&p%
* quvanxV-L
* To change this template, choose Tools | Options and locate the template under Up:<=Kgci
* the Source Creation and Management node. Right-click the template and choose Gcb|W&
* Open. You can then make changes to the template in the Source Editor. H*bs31i{
*/ *loOiM\5a
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package com.tot.count; =
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import tot.db.DBUtils; CH
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import java.sql.*; 7T"XPV|W6
/** 6Z`R#d #I
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* @author Ug:\
*/ =l.+,|ZH!
public class CountControl{ (YY~{W$w(
private static long lastExecuteTime=0;//上次更新时间 })w*m
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xil[#W]7Ge
/** Creates a new instance of CountThread */ n39t}`WIl
public CountControl() {} U~W?s(Cy%
public synchronized void executeUpdate(){ DAwqo.m
Connection conn=null; 4O:W#bx
PreparedStatement ps=null; `fNG$ODL
try{ 6G}+gqbX
conn = DBUtils.getConnection(); JT9N!CGZ
conn.setAutoCommit(false); lc_E!"1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); hoT/KWD,
for(int i=0;i<CountCache.list.size();i++){ {V1Pp;A
CountBean cb=(CountBean)CountCache.list.getFirst(); y7S4d~&
CountCache.list.removeFirst(); LTJc,3\,
ps.setInt(1, cb.getCountId()); [ >^PRs
ps.executeUpdate();⑴ H'MJ{r0,
//ps.addBatch();⑵ N$xtHtz8"
} SlSM+F
//int [] counts = ps.executeBatch();⑶ Fkf97Oi
conn.commit(); q~L^au8
}catch(Exception e){ 341?0%=
e.printStackTrace(); 2Bk$ lx7
} finally{ M7>(hVEAW'
try{ l{VSb92f
if(ps!=null) { x f4{r+
ps.clearParameters(); ~^^ NHq
ps.close(); 9s}Kl($
ps=null; ;pD)m/$h`
} !;6Jng%
}catch(SQLException e){} \([WH!7
DBUtils.closeConnection(conn); =SD\Q!fA
} ]APvp.Tw:
} 6DL[aD
public long getLast(){ "+?Cz!i
return lastExecuteTime; e4I^!5)N
} &x-TW,#Ks
public void run(){ xsjO)))f
long now = System.currentTimeMillis(); V@d)?T
if ((now - lastExecuteTime) > executeSep) { M[~{Vd
//System.out.print("lastExecuteTime:"+lastExecuteTime); y[O-pD`
//System.out.print(" now:"+now+"\n"); fag^7r z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); M,3wmW&d6
lastExecuteTime=now; nK3k]gLc{
executeUpdate(); h{lDxOH*
} ~#}Dx
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else{ ni
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ZyR_6n>L$
} 4gdY`}8b^}
} ^D@b;EyK
} xx*2?i
//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 >EXb|vw
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类写好了,下面是在JSP中如下调用。 .BO<
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<% @\(v X ]
CountBean cb=new CountBean(); OlxX.wP
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); R*1kR|*_)
CountCache.add(cb); \g-j9|0
out.print(CountCache.list.size()+"<br>"); WW@"Z}?k
CountControl c=new CountControl(); pz_e =xr
c.run(); |!d"*.Q@F
out.print(CountCache.list.size()+"<br>"); l{P\No
%>