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: ^*$!9~
w;AbJCv2
CountBean.java G^K;+& T
4K`b?{){+a
/* $qg2@X.
* CountData.java pMViq0
* Q7v1xBM
* Created on 2007年1月1日, 下午4:44 iRG6Cw2
* $kmY[FWu?
* To change this template, choose Tools | Options and locate the template under l"X,[
* the Source Creation and Management node. Right-click the template and choose &c&TQkx
* Open. You can then make changes to the template in the Source Editor. 1?8M31
*/ T9r6,yY
Y|hd!C-x
package com.tot.count; ks%;_~b
-p7
HQ/
/** L5KcI
* AFYdBK]
* @author ]S9Z5l0
*/ Ow5VBw(
public class CountBean { UMD\n<+cG,
private String countType; x00'wY|
int countId; wnXU=
/** Creates a new instance of CountData */ E1Q#@*rX>
public CountBean() {} awQGu,<N
public void setCountType(String countTypes){ })(robBkA
this.countType=countTypes; !-%%94 Q
} u:W/6QS
public void setCountId(int countIds){ 152s<lu1Z
this.countId=countIds; lm&^`Bn)
}
gy|o#&e]%
public String getCountType(){ s)-bOZi
return countType; ".( G,TW
} &><b/,]
public int getCountId(){ tr/.pw6
return countId; ?GLCd7TP
} $X\2h+ Os
} zO$r
'T7 3V
CountCache.java vAeVQ~
r_tt~|s,>
/* aAn p7\7
* CountCache.java MMD=4;X
* \xC#Zs[<
* Created on 2007年1月1日, 下午5:01 K g.O2F77
* `0q=Z],
* To change this template, choose Tools | Options and locate the template under 7z/O#Fbs
* the Source Creation and Management node. Right-click the template and choose u:l<NWF^
* Open. You can then make changes to the template in the Source Editor. RwrRN+&s\
*/ z?|bs?HKS
8+Gwv
SDU
package com.tot.count; >T0`( #Lm
import java.util.*; r5(efTgAd+
/** s+&0Z3+
* N$:-q'hX
* @author swJQwY
*/ Y;g\ @j
public class CountCache { =kK%,Mr
public static LinkedList list=new LinkedList(); _E6N*ORV
/** Creates a new instance of CountCache */ zq ?xY`E
public CountCache() {} 8$X3 J[_j
public static void add(CountBean cb){ /?TR_>
if(cb!=null){ ;AL:VU
list.add(cb); @g" vuaG}
} {/aHZ<I&^h
} Vr%ef:uVV
} 1B~Z1w
cb{"1z
CountControl.java \,v+ejhw
2<w vO 9
/* %AWc`D
* CountThread.java mZM7 4!4X
* ]TcQGW@'
* Created on 2007年1月1日, 下午4:57 [io|qLr}\
* V(io!8,
* To change this template, choose Tools | Options and locate the template under Z^_zcH'
* the Source Creation and Management node. Right-click the template and choose vO/ 3bu}
* Open. You can then make changes to the template in the Source Editor. Vu E$-)&)
*/ ]P>XXE;[
Y)(yw \&v
package com.tot.count; WoNY8
8hT
import tot.db.DBUtils; ]-SJ";aU
import java.sql.*; /?z3*x
/** 9 v8^uPA
* #<u;.'R
* @author ~0?B
*/ 6mIK[Qnp
public class CountControl{ PqF&[M<)
private static long lastExecuteTime=0;//上次更新时间
cJTwgm?
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tL<.B
/** Creates a new instance of CountThread */ w
$`w
public CountControl() {} ^7=7V0>,:
public synchronized void executeUpdate(){ E2>+V{TF
Connection conn=null; \.Op6ECV9
PreparedStatement ps=null; :IfwhI)
try{ x5/&,&m`%
conn = DBUtils.getConnection(); /s=veiH
conn.setAutoCommit(false); p7r/`_'|
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); tp&|*M3
for(int i=0;i<CountCache.list.size();i++){ cKoW5e|u
CountBean cb=(CountBean)CountCache.list.getFirst(); @tD (<*f+
CountCache.list.removeFirst(); WNQ<XBqAw
ps.setInt(1, cb.getCountId()); A&WC})H5
ps.executeUpdate();⑴ `c-omNu
//ps.addBatch();⑵ 'ShK7j$
} 6Q_A-X3hk
//int [] counts = ps.executeBatch();⑶ ev_' .t'
conn.commit(); Q[|*P ] w
}catch(Exception e){
R*S:/s
e.printStackTrace(); ;G3?Sa7+
} finally{ T5.^
w
try{ m&'!^{av
if(ps!=null) { ,j.bdlI#
ps.clearParameters(); jcBZ#|B7;
ps.close(); 3hUP>F8
ps=null; /m 7~-~$V
} Z{yH:{Vk
}catch(SQLException e){} 2\gIjXX"
DBUtils.closeConnection(conn); ?N!kYTR%}
} ~#}T|
} 8VO];+N
public long getLast(){ K(d+t\ca
return lastExecuteTime; zZ<*
}
~vM99hW
public void run(){ }@tgc?CD
long now = System.currentTimeMillis(); jh`[Y7RJO
if ((now - lastExecuteTime) > executeSep) { rzLW@k
//System.out.print("lastExecuteTime:"+lastExecuteTime); zEukEA^9`
//System.out.print(" now:"+now+"\n"); 8]R{5RGy
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); n5^57[(
lastExecuteTime=now; wEJzLFCn
executeUpdate(); v=cQ`nou
} 3T4HX|rC
else{ WY!4^<|w"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); f#w
u~*c
} 1KBGML-K3
} WjM7s]ZRv
} (+/d*4
//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 NuD|%Ebs
{>~9?Xwh
类写好了,下面是在JSP中如下调用。 `<M>"~W
RgQs`aI
<% `+>K)5hrR
CountBean cb=new CountBean(); 2+~gZxHq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); :Q@/F;Z?
CountCache.add(cb); :XG~AR/
out.print(CountCache.list.size()+"<br>"); %2g<zdab
CountControl c=new CountControl(); 1<_/Qu>V
c.run(); AYNdV(
out.print(CountCache.list.size()+"<br>"); ,u)jZ7
%>