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: c3
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CountBean.java +pFz&)?
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/* `nizGg~1
* CountData.java 1:&$0jU&U
* #Kh`ATme
* Created on 2007年1月1日, 下午4:44 #JW1JCT
* z?gJHN<
* To change this template, choose Tools | Options and locate the template under ~P/G^cV3s
* the Source Creation and Management node. Right-click the template and choose B[$SA-ZHi
* Open. You can then make changes to the template in the Source Editor. QWxQD'L'
*/ 5S7Z]DXiT8
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package com.tot.count; |
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/** +L49
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* PAc~p8S
* @author t)m4"p7
*/ /0\pPc*kA{
public class CountBean { !PQRlgcG
private String countType; UG!&n@R
int countId; :heJ5*!,
/** Creates a new instance of CountData */ jxoEOEA
public CountBean() {} q OXL(
public void setCountType(String countTypes){ zCQv:.0L
this.countType=countTypes; ^Gyl:hN
} )l"0:1I g
public void setCountId(int countIds){ EP8LJzd"
this.countId=countIds; t^[{8,N
} ~ACB#D%
public String getCountType(){ ^Uf`w7"iY
return countType; \.{JS>!
} F-R`'{ ka
public int getCountId(){ mrbIoN==`
return countId;
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} F0!r9U((
} $K iMu
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CountCache.java %z.G3\s0
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/* "2h#inS
* CountCache.java 6RF01z|~_
* 5 4OYAkPCk
* Created on 2007年1月1日, 下午5:01 J\%:jg( m
* K1hw'AaQ
* To change this template, choose Tools | Options and locate the template under PU>;4l
* the Source Creation and Management node. Right-click the template and choose SB;Wa%
* Open. You can then make changes to the template in the Source Editor. h}oQr0"c
*/ \x+DEy'4;5
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package com.tot.count; }Q%>Fv
import java.util.*; :.~a[\C@V<
/** c`>\R<Z ]
* nFP2wvFM
* @author UtutdkaS
*/ 8fN0"pymo
public class CountCache { a~%ej.)l
public static LinkedList list=new LinkedList(); ,'9tR&S$_
/** Creates a new instance of CountCache */ Za} |Ee
public CountCache() {} Cb13 Qz
public static void add(CountBean cb){ }}2kA
if(cb!=null){ aw 7f$Fqk
list.add(cb); j@ "`!uPz
} ^DH*@M
} !69^kIi$
} e%P;Jj476
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CountControl.java X=hgLK^3<,
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/* {$t*Mb0
* CountThread.java 1^;h:,e6
* {aL$vgYT1
* Created on 2007年1月1日, 下午4:57 4Rm3'Ch
*
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* To change this template, choose Tools | Options and locate the template under PYUY bRn
* the Source Creation and Management node. Right-click the template and choose sHuz10
* Open. You can then make changes to the template in the Source Editor. D6]$P%t9
*/ JA}'d7yEa
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package com.tot.count; KCu6:)6'
import tot.db.DBUtils; q+z\Y?
import java.sql.*; ""+*Gn7^8
/** Z:hrrq9
* kziBHis!
* @author 9H}&Ri%
*/ =tNiIU
public class CountControl{ acZHb[w
private static long lastExecuteTime=0;//上次更新时间 C]H <L#)ZU
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8_m9CQ6 i
/** Creates a new instance of CountThread */ HH#i.s2
public CountControl() {} jq]"6/xxb
public synchronized void executeUpdate(){ :U q]~e
Connection conn=null; ?>8zU;Aj
PreparedStatement ps=null; DRoxw24
try{ E,fp=.
conn = DBUtils.getConnection(); (3h*sd5ly
conn.setAutoCommit(false); [8P2V
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w2+]C&B*
for(int i=0;i<CountCache.list.size();i++){ 5r<(Z0
CountBean cb=(CountBean)CountCache.list.getFirst(); /vDF<HVzm
CountCache.list.removeFirst(); h /QP=Zd
ps.setInt(1, cb.getCountId()); fti|3c
ps.executeUpdate();⑴ ;QQ7vo
//ps.addBatch();⑵ @>IjfrjV
} KL mB
//int [] counts = ps.executeBatch();⑶ emB D@r
conn.commit(); O`jA-t
}catch(Exception e){ PL$F;d
e.printStackTrace(); ;cn.s,
} finally{ k#5e:VOb
try{ -!>ZATL<B
if(ps!=null) { X9A[
ps.clearParameters(); 9sj W
ps.close(); AdW2o|Uap
ps=null; Mgs|*u-5
} FqxOHovE
}catch(SQLException e){} Qsxkw
DBUtils.closeConnection(conn); X&?lDL7?
} i;zGw.;Q
} (OcNC/9
public long getLast(){ p}DF$k%`
return lastExecuteTime; R(83E
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} ]MLLr'6?
public void run(){ niEEm`"
long now = System.currentTimeMillis(); 0o$HC86w
if ((now - lastExecuteTime) > executeSep) { s|j<b#<xQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); KbdfSF$
//System.out.print(" now:"+now+"\n"); *\:_o5o%[T
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -f2`qltjb
lastExecuteTime=now; ]|t.wr3AU
executeUpdate(); 1R%`i'$/
} 8C,utjy
else{ vZeYp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EY&C[=
} <S8W~wC
} VUC <0WV
} ;#yu"6{
//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 c`i=(D<
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类写好了,下面是在JSP中如下调用。 LbX6p
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<% y^QYlZO
CountBean cb=new CountBean(); B.mbKntK)R
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); .)@tXH=}+
CountCache.add(cb); myWmU0z/
out.print(CountCache.list.size()+"<br>"); 8f,'p}@!d
CountControl c=new CountControl(); Z0ncN])
c.run(); E/7vIg
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out.print(CountCache.list.size()+"<br>"); ~0F9x9V
%>