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: q%;cu1^"M
qco'neR"z
CountBean.java [l5jPL}6
~q566k!Ll!
/* 9/0H,qZc
* CountData.java *>=tmW;%
* }}TPu8Rl
* Created on 2007年1月1日, 下午4:44 /8qR7Z^HZ
* Wu$ryX
* To change this template, choose Tools | Options and locate the template under a[~[lk=7
* the Source Creation and Management node. Right-click the template and choose GCN-T1HvA2
* Open. You can then make changes to the template in the Source Editor. Vp]7n!g4l
*/ +-'F]?DN'
R|qrK
package com.tot.count; [m:cO6DM,
_1gNU]"
/** _$>);qIP4
* aF?_V!#cT
* @author vf3) T;X>
*/ geyCS3
:p
public class CountBean { Lbz/M_G
private String countType; @QmN= X5
int countId; Gxe)5,G
/** Creates a new instance of CountData */ i`F5
public CountBean() {} ZiuD0#"!
public void setCountType(String countTypes){ C%yH}T\s
this.countType=countTypes; As)?~dV
} F!#)l*OX;
public void setCountId(int countIds){ im&N&A
this.countId=countIds; A Qjv?
4)T
} R5=J :o
public String getCountType(){ yP$esDP
return countType; (9%?ik
} =_k
public int getCountId(){ 8wkhbD|;
return countId; r[Pp[g-J
} 30^q_|l:]
} O.Pp*sQ^
++,I`x+p
CountCache.java A` _dj}UF
6t; ;Fz
/* q("XS
* CountCache.java h<&GdK2U+
* 4Px|:7~wT8
* Created on 2007年1月1日, 下午5:01 Wd;t(5Xl
* 1<m`38'
* To change this template, choose Tools | Options and locate the template under L-?ty@-i
* the Source Creation and Management node. Right-click the template and choose x*z[(0g!
* Open. You can then make changes to the template in the Source Editor. Jt]RU+TB
*/ Q|o$^D,
[&99#7B
package com.tot.count; x@43ZH_
import java.util.*; y$7Ys:R~
/** aWTurnee^
*
ZJs~,Q
* @author D1y`J&A>Q
*/ -hnNaA
public class CountCache { G)s.~ T
public static LinkedList list=new LinkedList(); <1I4JPh>x
/** Creates a new instance of CountCache */ f{VV U/$
public CountCache() {} |Yw k
public static void add(CountBean cb){ 6inAnC@I
if(cb!=null){ >C_G~R
list.add(cb); 3mU~G}ig
} O1o>eDE5A
} Zm*d)</>
} CJN~p]\
bh5D}w
CountControl.java =|AYT6z,
}d}sC\>U
/* %N&.B
* CountThread.java %7mGMa/
* n32"cFPpT
* Created on 2007年1月1日, 下午4:57 _s@PL59,
* '-A;B.GV%
* To change this template, choose Tools | Options and locate the template under 5XX)8gAo
* the Source Creation and Management node. Right-click the template and choose ')q4d0B`"
* Open. You can then make changes to the template in the Source Editor. Ci-Ze j
*/ FLG"c690
tcoG;ir
package com.tot.count; A^).i_
import tot.db.DBUtils; '8)kFR^9
import java.sql.*; 8'@5X-nD
/** 15J"iN2"W
* F&!vtlV)
* @author ]CLM'$
*/ toGd;2rl
public class CountControl{ ?0:]%t18
private static long lastExecuteTime=0;//上次更新时间 t!3s@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 O#;sY`fy_M
/** Creates a new instance of CountThread */ Y)/|C7~W
public CountControl() {} %bTuE' `b
public synchronized void executeUpdate(){ 4Lg
,J9
Connection conn=null; h%F.h![*
PreparedStatement ps=null; 9l~D}5e7
try{ 6HBDs:
conn = DBUtils.getConnection(); 1A'eH:$
conn.setAutoCommit(false); RgV3, z
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); bj@sci(1?
for(int i=0;i<CountCache.list.size();i++){ GFLat
CountBean cb=(CountBean)CountCache.list.getFirst(); =$4I}2
CountCache.list.removeFirst(); f@YdL6&d-
ps.setInt(1, cb.getCountId()); iw MxTty
ps.executeUpdate();⑴ A'`F Rx(
//ps.addBatch();⑵ F<{,W-my `
} Az y`4
//int [] counts = ps.executeBatch();⑶ .g}N@
conn.commit(); 0fX` >-X
}catch(Exception e){ 8GW+:
e.printStackTrace(); ORrZu$n`p
} finally{ yq|yGf(4&
try{ Mrgj*|
if(ps!=null) { D|(\5]:R
ps.clearParameters(); hO[_ _j8
ps.close(); |oU I2<"
ps=null; KE"6I
} AJ6l#j-
}catch(SQLException e){} Kw"e4 a
DBUtils.closeConnection(conn); rzHBop-8
} rK'Lvt@w
} b||usv[or
public long getLast(){ J:W+'x`@
return lastExecuteTime; #pPOQv:~
} .*YF{!R`h
public void run(){ )B
$Q
long now = System.currentTimeMillis(); QWa@?BO2p
if ((now - lastExecuteTime) > executeSep) { W8bp3JX"
//System.out.print("lastExecuteTime:"+lastExecuteTime); F8<G9#%s\
//System.out.print(" now:"+now+"\n"); ByP<-Deh
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !0hyp |F:>
lastExecuteTime=now; \E,2VM@6
executeUpdate(); ?=4oxPe
} ox`Zs2-a
else{ ppn 8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <QvVPE}z
} RuYIG?J=/
} 67&IaDts
} I)1ih
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 Mj1f;$
:(ql=+vDb4
类写好了,下面是在JSP中如下调用。 D$4GNeB+#
'z,kxra|n
<% \5&Mg81
CountBean cb=new CountBean(); R98YGW_
dT
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^@8XJ[C,_
CountCache.add(cb); `},:dDHI
out.print(CountCache.list.size()+"<br>"); :k?`gm$
CountControl c=new CountControl(); ;/kd.Q
c.run(); B|a <=~
out.print(CountCache.list.size()+"<br>"); Dks n
%>