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: >PdYQDyVS
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CountBean.java tSX<^VER7
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/* ~ED8]*H|`
* CountData.java |"h# Q[3
* 0G`_dMN
* Created on 2007年1月1日, 下午4:44 Y"~Tf{8
* Y+5nn
* To change this template, choose Tools | Options and locate the template under 8|kr|l
* the Source Creation and Management node. Right-click the template and choose e~C5{XEE
* Open. You can then make changes to the template in the Source Editor. Sq^f}q
*/ qW*JB4`?a
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package com.tot.count; 4FSA:]o-
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/** XFpII45
* &KinCh7l L
* @author PI_MSiYQ
*/ zUX%$N+w}>
public class CountBean { sq
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private String countType; KwGk8$ U
int countId; VN!`@Ci/
/** Creates a new instance of CountData */ S+(TRIjk
public CountBean() {} q =sEtH=
public void setCountType(String countTypes){ ":s1}A
this.countType=countTypes; al>^}:
} lbM)U
public void setCountId(int countIds){ A[lbBR
this.countId=countIds; 7<{g+Q~7*
} p!qV!:
public String getCountType(){ ^Ud1 ag!-
return countType; \a\-hm
} U9k;)fK
public int getCountId(){ "f^s*I
return countId; -*xm<R],
} B-Bgk
} ]D(!ua5|x`
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CountCache.java B#RBR<MFC
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/* y/U(v"'4U
* CountCache.java g '2'K
* %04N"^mT'~
* Created on 2007年1月1日, 下午5:01 6*yt^[W
* Qtj.@CGB
* To change this template, choose Tools | Options and locate the template under eeKErpj8A
* the Source Creation and Management node. Right-click the template and choose 05=
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* Open. You can then make changes to the template in the Source Editor. /{Ff)<Q.Z
*/ :)f/>-
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package com.tot.count; *sNZ.Y:.
import java.util.*; 0($@9k4!/
/** \@G
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* X!=E1TL
* @author b(^g v
*/ `PML4P[
public class CountCache { }dnO7K
public static LinkedList list=new LinkedList(); I+nKaN+8i
/** Creates a new instance of CountCache */ G@s]HJ:
public CountCache() {} j7L uN
public static void add(CountBean cb){ LxD >eA
if(cb!=null){ wHneVqI/U
list.add(cb); \HR<^xY
} "},0Cs
} ODS8bD0!i
} Md!L@gX6<
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CountControl.java QuG=am?l`
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/* M#<U=Ha
* CountThread.java <'s_3AC
* 8?p40x$m%
* Created on 2007年1月1日, 下午4:57 %V r vu5
* :|j,x7&/{
* To change this template, choose Tools | Options and locate the template under 21(8/F ~{
* the Source Creation and Management node. Right-click the template and choose hC1CISm.U
* Open. You can then make changes to the template in the Source Editor. zJ-_{GiM*L
*/ |Z\?nZ~
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package com.tot.count; >%qk2h>
import tot.db.DBUtils; -P I$SA,
import java.sql.*; ]IX6>p,
/** kR+xInDM*
* CKC%|xke
* @author y2"PKBK\_
*/ Xx.4K>j+j
public class CountControl{ :exgdm;N
private static long lastExecuteTime=0;//上次更新时间 c?@WNv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Vz=ByyC
/** Creates a new instance of CountThread */ 82w;}(!
public CountControl() {} l,z#
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public synchronized void executeUpdate(){ _hM
#*?}v
Connection conn=null; wUUDq?!k\
PreparedStatement ps=null; M5$YFGGR
try{ %}< e;t-O
conn = DBUtils.getConnection(); >j5,Z]
conn.setAutoCommit(false); h8R3N?S3#
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R$[nYw
for(int i=0;i<CountCache.list.size();i++){ XwI~ 0
CountBean cb=(CountBean)CountCache.list.getFirst(); !m7`E
CountCache.list.removeFirst(); ].E89 _|O
ps.setInt(1, cb.getCountId()); jZRf{
ps.executeUpdate();⑴ n^} -k'l
//ps.addBatch();⑵ fY)Dx c&ue
} #Az#dt]H
//int [] counts = ps.executeBatch();⑶ Z )Imj&;
conn.commit(); fW/G_
}catch(Exception e){ ixK&E#
e.printStackTrace(); u\L=nCtLby
} finally{ 4!%@{H`3
try{ M8 4{u!>[
if(ps!=null) { =bn(9Gm!J
ps.clearParameters(); Vjv~RNGF
ps.close(); 1_AB;^
ps=null; nC-=CMWWr
} [73 \jT
}catch(SQLException e){} zWN/>~}U\
DBUtils.closeConnection(conn); tyEa5sy4
} +
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} 0F"W~OQ6
public long getLast(){ ~&zrDj~FI
return lastExecuteTime; MCPVql`+`q
} }]dK26pX
public void run(){ &E{CQ#k
long now = System.currentTimeMillis(); 8$!&D&v
if ((now - lastExecuteTime) > executeSep) { +XaRwcLC.
//System.out.print("lastExecuteTime:"+lastExecuteTime); ySfot`LQ
//System.out.print(" now:"+now+"\n"); &m=GkK
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); dA)JR"r2
lastExecuteTime=now; o'oA.'ul
executeUpdate(); (8Q0?SZN
} )K=%s%3h<
else{ 3K8#,TK3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -?jI{].:8
} A*1-2
} /G{;?R
} {B!LhvYAH
//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 H@+1I?l
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类写好了,下面是在JSP中如下调用。 |4$.mb.
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<% )[t zAaP7
CountBean cb=new CountBean(); (-<s[VnXP
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Ri<7!Y?l
CountCache.add(cb); fX
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out.print(CountCache.list.size()+"<br>"); OouIV3
CountControl c=new CountControl(); u[{j;l(
c.run(); ce3UB~Q
out.print(CountCache.list.size()+"<br>"); a#huK~$~
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