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: YujR}=B!/
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CountBean.java 6%a9%Is!O
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/* A=Y A #0
* CountData.java '^n,)oA/G
* .Ei#mG-=}&
* Created on 2007年1月1日, 下午4:44 D_N0j{E
* I[6ft_*
* To change this template, choose Tools | Options and locate the template under w4Uo-zr@
* the Source Creation and Management node. Right-click the template and choose K/YXLR +
* Open. You can then make changes to the template in the Source Editor. _4f=\
*/
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package com.tot.count; n2(`O^yd7C
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/** ~W2Od2p!
* 4C#r=Uw`
* @author eP|_
*/ yMz dM&a!*
public class CountBean { 6Y%{ YQ}s|
private String countType; 2@6Qifxd@
int countId; Ueu~803~
/** Creates a new instance of CountData */ N79?s)l:K
public CountBean() {} 3Q#Tut
public void setCountType(String countTypes){ Ez/>3:;
this.countType=countTypes; i*]$_\yl"
} dEI]|i
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public void setCountId(int countIds){ hcqg94R#_
this.countId=countIds; M?d (-en
} }Ip1|Gj
public String getCountType(){ o(gV;>I
return countType; h3[x ZJO
} o?g9Grk
public int getCountId(){ TFNB%|
return countId; Hmx
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} kz"QS.${
} h+!@`c>)Y
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CountCache.java FfX*bqy
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/* <^w4+5sT/
* CountCache.java OJ1MV 7&
* 9'=ZxV
* Created on 2007年1月1日, 下午5:01 V2SHF
* Q-?6o
* To change this template, choose Tools | Options and locate the template under m@y<wk(
* the Source Creation and Management node. Right-click the template and choose ;lQ>>[*
* Open. You can then make changes to the template in the Source Editor. }0C v J4
*/ hRNnj
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package com.tot.count; -uNM_|MO
import java.util.*; O9*l6^Scw
/** sE])EwZ
* =p[a Cb
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* @author ".{'h
*/ z.~jqxA9
public class CountCache { (j-_iOQ]i+
public static LinkedList list=new LinkedList(); '-BD.^!!
/** Creates a new instance of CountCache */ Eq=j+ch7
public CountCache() {} 2@!B;6*8q
public static void add(CountBean cb){ 48,uO!
if(cb!=null){ 3ESrd"W=
list.add(cb); !A:d9 k
} Nwg?(h#
} =PjxMC._
} -Rwx`=6tV
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CountControl.java vO)]~AiB
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/* q $=[v
* CountThread.java C{>dE:*K^
* fizL_`uMqb
* Created on 2007年1月1日, 下午4:57 iEx4va-j
* &bigLe
* To change this template, choose Tools | Options and locate the template under !E6QED"
* the Source Creation and Management node. Right-click the template and choose .JBTU>1]_n
* Open. You can then make changes to the template in the Source Editor. t[ZGY,8
*/ } J`cRDO
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package com.tot.count; UZ1Au;(|
import tot.db.DBUtils; :eH\9$F`x;
import java.sql.*; YH&q5W,KX
/** !ou;yE&<,
* tC5>K9Ed
* @author (W.G&VSn)
*/ 4N5\sdi
public class CountControl{ /@1pm/>ZaN
private static long lastExecuteTime=0;//上次更新时间 Fd#Zu.Np
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 AYAbq}'Yt
/** Creates a new instance of CountThread */ P9x':I$
public CountControl() {} x@@bC=iY$
public synchronized void executeUpdate(){ 6 $K@s
Connection conn=null; 3:>hHQi
PreparedStatement ps=null; qJJ},4}
try{ vwzElZ{C:v
conn = DBUtils.getConnection(); >IipWTVo<
conn.setAutoCommit(false); lHFk~Qp[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); y@<&A~Cl^
for(int i=0;i<CountCache.list.size();i++){ V}ls|B$Y
CountBean cb=(CountBean)CountCache.list.getFirst(); |'j,|^<
CountCache.list.removeFirst(); }nptmc
ps.setInt(1, cb.getCountId()); QabLMq@n`
ps.executeUpdate();⑴ [@2$W?0i
//ps.addBatch();⑵ p||mR
} !AG {`[b
//int [] counts = ps.executeBatch();⑶ ZcN#jnb0/
conn.commit(); A6
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}catch(Exception e){ R+El/ya:6
e.printStackTrace(); k~?5mUyK<
} finally{ Yq'D-$@
try{
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if(ps!=null) { %a]Imsm
ps.clearParameters(); J06D_'{
ps.close(); W![~"7?
ps=null; wG73GD38
} i v.G
}catch(SQLException e){} O
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DBUtils.closeConnection(conn); !="8ok+
} EMDYeXpV
} `fE'$2
public long getLast(){ '.jYu7
return lastExecuteTime; &A=c[pc
} z0%tBgqY(
public void run(){ ?<T=g
long now = System.currentTimeMillis(); h^,av^lg^
if ((now - lastExecuteTime) > executeSep) { "ji+~%`^[t
//System.out.print("lastExecuteTime:"+lastExecuteTime); Ko)f:=Qo
//System.out.print(" now:"+now+"\n"); |7Qe{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); UY .-Qt
lastExecuteTime=now; Mcq!QaO}&
executeUpdate(); /(?s\}O
} -!V{wD3,B
else{ ]^Xj!01~
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 2qQ;U?:q
} yF1p^>*ak&
} B4 5#-V
} aj/+#G2
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 xo2jfz
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类写好了,下面是在JSP中如下调用。 ah,"c9YX
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<% LB[?kpy
CountBean cb=new CountBean(); [KCR@__
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ~Orz<%k.
CountCache.add(cb); X4+H8],)
out.print(CountCache.list.size()+"<br>"); R&$fWV;'
CountControl c=new CountControl(); V(g5Gn?
c.run(); `5"3Cj"M
out.print(CountCache.list.size()+"<br>"); drvrj~o:
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