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: jNrGsIY$
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CountBean.java R &T(S
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/* spd>.Cm`
* CountData.java won%(n,HT
* a?\
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* Created on 2007年1月1日, 下午4:44 `')3}
* NWb,$/7T
* To change this template, choose Tools | Options and locate the template under GZ*cV3Y`&
* the Source Creation and Management node. Right-click the template and choose Q6"r^wWx
* Open. You can then make changes to the template in the Source Editor. I9k o*f
*/ b[$l{RQ[?
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package com.tot.count; 3ef]3
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/** cKF 8(
* 4}fG{Bk
* @author o D:?fs]
*/ \BUr2]
public class CountBean { L[Tr"BW
private String countType; !XzRV?Ih;
int countId; R9fM9
/** Creates a new instance of CountData */ /R 2:Js
public CountBean() {} u@[D*c1!H
public void setCountType(String countTypes){ vKol@7%N
this.countType=countTypes; N\<M4fn
} V\X.AGc
public void setCountId(int countIds){ G|IO~o0+
this.countId=countIds; I:bi8D6
} vezX/x D?
public String getCountType(){ ^5j9WV
return countType; |c dQJW
} $WrDZU 2z
public int getCountId(){ h]vA%VuE'E
return countId; !);'Bk9o
} Ba6''?;G
} ([tbFI}A
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CountCache.java ~.yt
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/* MXSPD#gN
* CountCache.java G\|VTqu
* q<D'"7#.
* Created on 2007年1月1日, 下午5:01 vX/~34o]\
* |jO&qT]{
* To change this template, choose Tools | Options and locate the template under OUS@)Tyh
* the Source Creation and Management node. Right-click the template and choose zD7\Gv
* Open. You can then make changes to the template in the Source Editor. g}P.ksM
*/ ;r"YZs&Xd
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package com.tot.count; K"#np!Y)
import java.util.*; [|Jzs[
/** )TBBYCL3
* O: :X$O7
* @author ixE72bX
*/ d%u|)
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public class CountCache { FF)F%o+:w
public static LinkedList list=new LinkedList(); i|)<#Ywl
/** Creates a new instance of CountCache */ wh[XJ_xY
public CountCache() {} 2u/~#Rt&*
public static void add(CountBean cb){ W;eHDQ|
if(cb!=null){ RU>T?2
list.add(cb); BC9rsb
} g75)&U`>}
} -|"mB"Dc
} Qf6Vj,~N
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CountControl.java BD\xUjd?)Q
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/* ^8ZVB.Fv
* CountThread.java 9~SfZ,(
* gp$oQh#37;
* Created on 2007年1月1日, 下午4:57 Pp*|EW 1
* C;-9_;&
* To change this template, choose Tools | Options and locate the template under h%8[];*DpN
* the Source Creation and Management node. Right-click the template and choose hg/G7Ur"
* Open. You can then make changes to the template in the Source Editor. ?;ZTJ
*/ -WWa`,:
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package com.tot.count; WSz#g2a
import tot.db.DBUtils; 4nN%5c~=
import java.sql.*; 4@&8jZ)a
/** 1(CpTaa
* `b=?z%LuT
* @author CE=&ZHt9
*/ l&R~I6^E
public class CountControl{ EC<g7_0F
private static long lastExecuteTime=0;//上次更新时间 e23}'qb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $-Lk,}s.*
/** Creates a new instance of CountThread */ zWb>y
public CountControl() {} n,!PyJ
public synchronized void executeUpdate(){ Z@nWx]iz
Connection conn=null; K?+iu|$&
PreparedStatement ps=null; *yN+Xm8o
try{ jjN]*{s
conn = DBUtils.getConnection(); _DnZ=&=MA
conn.setAutoCommit(false); <5%x3e"7u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); jQxv`H
for(int i=0;i<CountCache.list.size();i++){ sgW*0o
CountBean cb=(CountBean)CountCache.list.getFirst(); {dM18;
CountCache.list.removeFirst(); fI9 TzpV
ps.setInt(1, cb.getCountId()); "g;^R/sfq
ps.executeUpdate();⑴ b) "bX}
//ps.addBatch();⑵ t:B~P,r
} Rf||(KC<
//int [] counts = ps.executeBatch();⑶ 7s+3^'
conn.commit(); +&6R(7XC
}catch(Exception e){ />=)=CGv;
e.printStackTrace(); ..`J-k
} finally{ hK5BOq!y
try{ tgCEz%
if(ps!=null) { se(ZiyHp
ps.clearParameters(); P~HzNC
ps.close(); j
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ps=null; .Zv@iL5
} rtd&WkU
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}catch(SQLException e){} d:cs8f4>
DBUtils.closeConnection(conn); 2+y<&[A8U
} ];P$w.0
} 1$2'N~`#U
public long getLast(){ dtD)VNkBZ
return lastExecuteTime; mxt fKPb
} Y3KKskhLx
public void run(){ .aTu]i3l_
long now = System.currentTimeMillis(); E&ou(Q={
if ((now - lastExecuteTime) > executeSep) { @0H}U$l
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1AiqB Rs
//System.out.print(" now:"+now+"\n");
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y7g^ ?6
lastExecuteTime=now; =|_:H$94
executeUpdate(); -T3 z@k
} =aR'S\<
else{ BV_rk^}Ur
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ~5g2~.&*
} ' P5ttI#|
} zg L0v5vk
} {=};<;_F
//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 Qk 2^p^ T6
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类写好了,下面是在JSP中如下调用。 N.R,[K
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<% L@xag-b
i
CountBean cb=new CountBean(); ^oaFnzJdf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); B7HNNX
CountCache.add(cb); W?is8r:
out.print(CountCache.list.size()+"<br>"); /o%J /|
CountControl c=new CountControl(); rV;X1x}l
c.run(); r1dP9MT\8
out.print(CountCache.list.size()+"<br>"); pD;'uEFBQ
%>