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: +gTnq")wnI
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CountBean.java Od'!v &
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/* MOyQ4<_
* CountData.java un[Z$moN"
* #5T+P8
* Created on 2007年1月1日, 下午4:44 +"a .,-f!
* ~)}npS;
* To change this template, choose Tools | Options and locate the template under D:llGdU#2
* the Source Creation and Management node. Right-click the template and choose P}H7WH
* Open. You can then make changes to the template in the Source Editor. S@zsPzw
*/ "7RQrz
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package com.tot.count; gQ*0Mk
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/** iwL\H a
* 8@qYzSx[
* @author
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*/ dKw*L|5
public class CountBean { r}9qK%C G.
private String countType; 4)iSz>
int countId; :t]YPt
/** Creates a new instance of CountData */ Fy<dk}@
public CountBean() {} koC2bX
public void setCountType(String countTypes){ )k3zOKZ;
this.countType=countTypes; K!k,]90Ko
} 8|?$KLz?F>
public void setCountId(int countIds){ K%>uSS?
this.countId=countIds; 9xC,i
)
} ZYrXav<
public String getCountType(){ -.1x! ~.jX
return countType; 8(D>ws$
} F`U%xn,
public int getCountId(){ uU6+cDp
return countId; 7[:9vY
} c0u!V+V%
} f>5{SoM
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CountCache.java b3x!tuQn
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/* U=p,drF,A
* CountCache.java A5+vz u^
* PV>-"2n
* Created on 2007年1月1日, 下午5:01 OR4!73[I
* J
\1&3r|R
* To change this template, choose Tools | Options and locate the template under eM+]KG)}
* the Source Creation and Management node. Right-click the template and choose N/Z3 EF_
* Open. You can then make changes to the template in the Source Editor. y_38;8ex
*/ "W|Sh#JF
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package com.tot.count; mTW0_!.
import java.util.*; $TL~SVHj;{
/** DTt/nmKAqJ
* #~q{6()e:
* @author mKPyM<Q
*/ L\5j"]
}`
public class CountCache { Ezm ~SY
public static LinkedList list=new LinkedList(); .ev'd&l.
/** Creates a new instance of CountCache */ ^$24231^
public CountCache() {} Io{)@H"f
public static void add(CountBean cb){ .3A66 O~zT
if(cb!=null){ I'
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list.add(cb); \QstcsEt
} l[l('-f
} SPeSe/
} 6YQ&+4
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CountControl.java [(5;jUmF@
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/* ]k_@F6 A
* CountThread.java //\ORJd
* (+38z)f
* Created on 2007年1月1日, 下午4:57 v1QE|@
* fnG&29x
* To change this template, choose Tools | Options and locate the template under UC;_}>
* the Source Creation and Management node. Right-click the template and choose b"t!nfgo
* Open. You can then make changes to the template in the Source Editor. $VhUZGuG>
*/ ,;'9PsIS^
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package com.tot.count; ngcXS2S_
import tot.db.DBUtils; jtV{Lf3<
import java.sql.*; j>+x|!k
/** +T+f``RcK
* =E8lpN'
* @author g9H~\w
*/ Ix^xL+Tm
public class CountControl{ j Aw&5,
private static long lastExecuteTime=0;//上次更新时间 B5IS-d
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 B8'" ^a^&-
/** Creates a new instance of CountThread */ i))S%!/r~
public CountControl() {} cV_nYcLkz
public synchronized void executeUpdate(){ f[HhLAVGK`
Connection conn=null; }L{en
PreparedStatement ps=null; ync2X{9D
try{ zJOjc/\
conn = DBUtils.getConnection(); G7DEavtr
conn.setAutoCommit(false); .ZFs+8qU>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); n@mWBUM
for(int i=0;i<CountCache.list.size();i++){ }>=k!l{
CountBean cb=(CountBean)CountCache.list.getFirst(); {^1GHU
CountCache.list.removeFirst(); \Q|1I
ps.setInt(1, cb.getCountId()); G@oY2sM"
ps.executeUpdate();⑴ 3aQWzEnh
//ps.addBatch();⑵ :t8(w>oW
} =M>1;Qr<Z/
//int [] counts = ps.executeBatch();⑶ D%N^iJC,9
conn.commit(); =2BGS\$#
}catch(Exception e){ j#"?Oe{_1
e.printStackTrace(); t(-noy)
} finally{ KtU I(*$`
try{ YBN@{P$
if(ps!=null) { _p\
ps.clearParameters(); qgvg
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ps.close(); L@2T
ps=null; }a,j1r_Hl&
} 5*xk8*
}catch(SQLException e){} xI55pj*
DBUtils.closeConnection(conn); H`G[QC
} DF-`nD
} b{=2#J-
public long getLast(){ ~EG`[cv
return lastExecuteTime; IExo#\0'6
} }+h/2D
public void run(){ [h+MA>%!
long now = System.currentTimeMillis(); bX:Y5o49
if ((now - lastExecuteTime) > executeSep) { lOt3^`
//System.out.print("lastExecuteTime:"+lastExecuteTime); %g{m12
//System.out.print(" now:"+now+"\n"); o"->RC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !s06uh
lastExecuteTime=now; B?'`\q)UL
executeUpdate(); nPj%EKdY4
} 8Gzc3
else{ hn#i,XnY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ya0L8`q
} !jL|HwlA
} UB }n=
} v=E V5#A
//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
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类写好了,下面是在JSP中如下调用。 Ci0: -IS
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<% dElOy?v
CountBean cb=new CountBean(); -@X?~4Idz
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); XZYpU\K
CountCache.add(cb); H'Bor\;[>
out.print(CountCache.list.size()+"<br>"); O l1[ o
CountControl c=new CountControl(); U8KB@E
c.run(); ATp7:Q
out.print(CountCache.list.size()+"<br>"); l69&-Nyg
%>