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: vP~F+z
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CountBean.java (x$k\H
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/* aQ~x$T|
* CountData.java Mm[%v
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* MA-$aN_(
* Created on 2007年1月1日, 下午4:44 ga~vQ7I_
* Zz3#Kt5t3
* To change this template, choose Tools | Options and locate the template under sy@k3wQ
* the Source Creation and Management node. Right-click the template and choose bo -Gh`
* Open. You can then make changes to the template in the Source Editor.
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*/ 7T2W%JT-,
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package com.tot.count; MK[spV
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/** y=j[v},4
* bL[PNUG
* @author m9B3]H
*/ g*tLqV
public class CountBean { _fyw
private String countType; <?J7Z|
int countId; 9H)uTyuNi
/** Creates a new instance of CountData */
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public CountBean() {} OVh/t#On
public void setCountType(String countTypes){ Uq+
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this.countType=countTypes; m5x>._7le
} $c y:G
public void setCountId(int countIds){ /pge 7P
this.countId=countIds; yED^/=\)}
} AeJM[fCMa
public String getCountType(){ f%}+.eD
return countType; 4
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} slmxit
public int getCountId(){ k?8W2fC
return countId; IGqmH=-
} JZnWzqFw
} 0Its;|
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CountCache.java 'OihA^e
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/* Y}#^n7*w~
* CountCache.java |zT0g]WH
* ^+wzm2i
* Created on 2007年1月1日, 下午5:01 y;>I'e
* !fV6KkV
* To change this template, choose Tools | Options and locate the template under :hr@>Y~r
* the Source Creation and Management node. Right-click the template and choose xXYens}
* Open. You can then make changes to the template in the Source Editor. <Ztda !
*/ G7202(w
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package com.tot.count; ii2Z}qe
import java.util.*; $^XPk#$m
/** $P@cS1sB
* '_<`dzz
* @author 3"hR:'ts
*/ .#eXNyCe
public class CountCache { >V$#Um?AXj
public static LinkedList list=new LinkedList(); 2r0!h98
/** Creates a new instance of CountCache */ )/AvWDKvO
public CountCache() {} Iq=B]oE
public static void add(CountBean cb){ 8WGM%n#q
if(cb!=null){ /t^lI%&
list.add(cb); }:8>>lQ
} S- \lN|
} 8JrGZ8Q4RM
} !491
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CountControl.java 9C 05
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/* <`*P/V
* CountThread.java C4uR5U
* U:|v(U$"?
* Created on 2007年1月1日, 下午4:57 [Z+,)-ke
* #dt2'V- ,
* To change this template, choose Tools | Options and locate the template under S}f<@-16P
* the Source Creation and Management node. Right-click the template and choose )89jP088V
* Open. You can then make changes to the template in the Source Editor. 11T\2&Q
*/ 8'[wa
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package com.tot.count; =4
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import tot.db.DBUtils; bx^EaXj(r
import java.sql.*; D5b_m|7%
/** c]r|I%D
* NKKOA
* @author g DG m32
*/ NGs9Jke2
public class CountControl{ TjK5UML
private static long lastExecuteTime=0;//上次更新时间 90ag!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 yy1r,dw
/** Creates a new instance of CountThread */ <3x#(ms!!
public CountControl() {} Lx{N%;t*E
public synchronized void executeUpdate(){ z\Y^x9
Connection conn=null; F.5b|&@
PreparedStatement ps=null; \KXEw2S
try{ z}tp0~C
conn = DBUtils.getConnection(); l,L=VDEz,
conn.setAutoCommit(false); \>`$x:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Av>j+O ;
for(int i=0;i<CountCache.list.size();i++){ (NC>[
CountBean cb=(CountBean)CountCache.list.getFirst(); ,b(S=r
CountCache.list.removeFirst(); vxT"BvN
ps.setInt(1, cb.getCountId()); ZcRm5Du~:
ps.executeUpdate();⑴ 3/=QZ8HA&-
//ps.addBatch();⑵ 1@S6[&_
} RT"2Us]*
//int [] counts = ps.executeBatch();⑶ vaOL6=[#:g
conn.commit(); d)ZSzq
}catch(Exception e){ %pkq ?9
e.printStackTrace(); %d J>8.jW@
} finally{ @qy*R'+
try{ =hOa
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if(ps!=null) { ZC*d^n]x.
ps.clearParameters(); 3a}`xCO5
ps.close(); mZVOf~9E
ps=null; KAcri<^G
} 2rtP.*dd
}catch(SQLException e){} PjW+V`
DBUtils.closeConnection(conn); c\{}FGC
} $#FlnM<=
} 97wy;'J[u
public long getLast(){ WbWW=(N'd
return lastExecuteTime; xBfe8lor
} LC\:xia{X
public void run(){ ,HkhK bQ
long now = System.currentTimeMillis(); z8 ;#H
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if ((now - lastExecuteTime) > executeSep) { aZ>\*1
//System.out.print("lastExecuteTime:"+lastExecuteTime); i!oj&&
//System.out.print(" now:"+now+"\n"); dKQV4dc>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ?67I|@^
lastExecuteTime=now; DjzBG*f/
executeUpdate(); o[[r_v_d
} r{R7"
else{ 3ZlGbP#3w
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); @dCPa7:>&
} _xgVuJ
} 7XWBI\SW
} $,,>R[; w
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 hYXZ21(K#
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类写好了,下面是在JSP中如下调用。 LA`VqJ
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<% "5JNXo,H
CountBean cb=new CountBean(); [H%?jTQ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); n=o'ocdS)
CountCache.add(cb); tm1UH 4
out.print(CountCache.list.size()+"<br>"); 6Hbf9,vI
CountControl c=new CountControl(); q VdC ?A|
c.run(); Qb't*2c%
out.print(CountCache.list.size()+"<br>"); r82o[+$u0K
%>