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: MwfOy@|N
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CountBean.java -tnQCwq#
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/* d/}SAvtt
* CountData.java etd&..]J
* *26334B.R
* Created on 2007年1月1日, 下午4:44 {CR 5K9
* 16L]=&@
* To change this template, choose Tools | Options and locate the template under 50
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* the Source Creation and Management node. Right-click the template and choose T \CCF
* Open. You can then make changes to the template in the Source Editor. >Bs#Xb_B]
*/ %lX%8Z$v
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package com.tot.count; G[8in
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/** K_
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* LGc&o]k
* @author ~>0qZ{3J_
*/ Hg9CZMko
public class CountBean { _BFOc>0
private String countType; Dw7vv]+ S
int countId; yQ3OL#
/** Creates a new instance of CountData */ &QG6!`fK}3
public CountBean() {} VdP`a(Yd;
public void setCountType(String countTypes){ i/b'4o=8
this.countType=countTypes; XX1Il;1G#
} Iyd?|f"
public void setCountId(int countIds){ T~fmk
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this.countId=countIds; %+ FG ,d
} [ >^PRs
public String getCountType(){ Q#(GI2F2#
return countType; 0 a~HiIh
} 1xU3#b&2tC
public int getCountId(){ GabYfUkO
return countId; }<PxWZ`,\
} ?:|-Dq,
} |v[ Rp=?]
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CountCache.java T6pLoaKu
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/* D0mI09=GtQ
* CountCache.java v`V7OD#:j]
* l;sy0S"DO]
* Created on 2007年1月1日, 下午5:01 >a1{397Y}
* _5MNMVLwW
* To change this template, choose Tools | Options and locate the template under \v6M:KR5/
* the Source Creation and Management node. Right-click the template and choose l%Gw_0.?e
* Open. You can then make changes to the template in the Source Editor. AF43$6KZP$
*/ ubu?S%`
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package com.tot.count; 7O`o ovW$
import java.util.*; ](eN@Xi&@
/** ^`SA'F,
* )2DQ>cm
* @author XhdSFxW}
*/ xyH/e*a
public class CountCache { 8F)G7
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public static LinkedList list=new LinkedList(); 577:u<Yt
/** Creates a new instance of CountCache */ ]APvp.Tw:
public CountCache() {} dr{y0`CCN
public static void add(CountBean cb){ -[OXSaf6
if(cb!=null){ Omi^>c4G
list.add(cb); ?EU\}N J
} |wox1Wt|E
} 8h<ehNX ^I
} I
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CountControl.java pPVRsXy
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/* 7([h4bg{
* CountThread.java 0)Rw|(Fpo]
* '!Gs>T+
* Created on 2007年1月1日, 下午4:57 0W`LVue
* _{jP;W
* To change this template, choose Tools | Options and locate the template under sA9&/p/
* the Source Creation and Management node. Right-click the template and choose -ng=l;
* Open. You can then make changes to the template in the Source Editor. 19(Dj&x
*/ >x3ug]Bu
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package com.tot.count; wFlvi=n/
import tot.db.DBUtils; e75UMWaeC
import java.sql.*; WxbsD S;
/** 6|J'>)
* 7GZgu$'
* @author I8H%=Kb?9
*/ IMQ]1uq0$
public class CountControl{ dSIH9D
private static long lastExecuteTime=0;//上次更新时间 U,1AfzlF
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /,5Z-Z*wq
/** Creates a new instance of CountThread */ Je4Z(kj 0
public CountControl() {} ^*R(!P^
public synchronized void executeUpdate(){ 9umGIQHnil
Connection conn=null; >EXb|vw
PreparedStatement ps=null; v&g0ta@
try{ gQ~5M'#
conn = DBUtils.getConnection(); g8ES8SM
conn.setAutoCommit(false); rZbEvS
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %Y4e9T".
for(int i=0;i<CountCache.list.size();i++){ ">dq0gD
CountBean cb=(CountBean)CountCache.list.getFirst(); U},=LsDsW4
CountCache.list.removeFirst(); I~'*$l
ps.setInt(1, cb.getCountId()); ZX
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ps.executeUpdate();⑴ -Uo?WXP]B'
//ps.addBatch();⑵ o@lWBfB*%e
} 1u]P4Gf=
//int [] counts = ps.executeBatch();⑶ p4VqV6LwD
conn.commit(); LF*Q!
}catch(Exception e){ Oajv^H,Em
e.printStackTrace(); %Hi~aRz
} finally{ |!d"*.Q@F
try{ =A[5=
k>
if(ps!=null) { tPHS98y
ps.clearParameters(); 1'6cGpZY
ps.close(); ZF#Rej?
ps=null; o%M<-l"!/
} OySy6IN]q
}catch(SQLException e){} _-cK{
DBUtils.closeConnection(conn); ,7|;k2
} Gie@JX
} Y9 r3XhVI
public long getLast(){ }bB`(B,m
return lastExecuteTime; h3u1K>R)
} z&nZ<ih
public void run(){ 7N2\8kP
long now = System.currentTimeMillis(); eIPG#A
if ((now - lastExecuteTime) > executeSep) { ~@I@} n
//System.out.print("lastExecuteTime:"+lastExecuteTime); p4X{"Z\mn
//System.out.print(" now:"+now+"\n"); =G-N`
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6k])Kl J2;
lastExecuteTime=now; m.%`4L^`T
executeUpdate(); A q#/2t
} #y"=Cz=1u7
else{ ,*,sw:=2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $*~Iu%Az
} g?/XZ5$a5
} ){Mu~P
} SKXBrD=-
//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 x.DzViP/
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类写好了,下面是在JSP中如下调用。 I#A2)V0P)
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<% NVIWWX9?
CountBean cb=new CountBean(); c^I0y!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #]KgUc5B
CountCache.add(cb); 8IY19>4'5J
out.print(CountCache.list.size()+"<br>"); yOHXY&
CountControl c=new CountControl(); K <`>O,
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c.run(); A{,n;;
out.print(CountCache.list.size()+"<br>"); Lue|Plm[y
%>