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: ]ge^J3az$u
<`VJU2
CountBean.java ;V(}F!U\z
W$ d{
/* VL,?91qwe
* CountData.java `OpC-Z&
* ObHz+qRG
* Created on 2007年1月1日, 下午4:44 = ,E(!Sp
* o dQ&0d
* To change this template, choose Tools | Options and locate the template under :?of./Df|
* the Source Creation and Management node. Right-click the template and choose WaZ@
* Open. You can then make changes to the template in the Source Editor. w<^2h}5
*/ @'| 6lG
Fn0LE~O}-8
package com.tot.count; *ytd.^@r
z@S8H6jM)S
/** =R8.QBVdN
* sMpC4E
* @author )<&CnK
*/ !5
:1'$d]H
public class CountBean { \iTPJcb5
private String countType; /iJhCB[QZ
int countId; ?ia[KLt"
/** Creates a new instance of CountData */ HFCFEamBMP
public CountBean() {} =.2cZwxX$
public void setCountType(String countTypes){ {m*J95[
this.countType=countTypes; Jj _+YfIM
} p 7E{es|J
public void setCountId(int countIds){ n[p9$W`
this.countId=countIds; VDI S`E
} >IydXmTy
public String getCountType(){ Spw=+z<<Ub
return countType; P`Wf'C^h
} JdNPfkOF
public int getCountId(){ nhaoh!8A6
return countId; B
qiq
} Ta5iY
}
} -tdON
cLk+( dn
CountCache.java
Tee3U%Y
sf&K<C](
/* \\pyu]z
* CountCache.java (Y@|h%1W
* MM)/B>c Qt
* Created on 2007年1月1日, 下午5:01 ykl=KR
* n'(n4qH2#s
* To change this template, choose Tools | Options and locate the template under vWU4ZBT8G
* the Source Creation and Management node. Right-click the template and choose Tqh Rs
* Open. You can then make changes to the template in the Source Editor. uN^qfJ'@
>
*/ @^jLYu|W
4]Nr$FY
package com.tot.count; >Zp]vK~s
import java.util.*; xM"XNT6b
/** qk{UO
<
* -(,6w?
* @author {mr)n3
*/ OM C|.[
public class CountCache { Kpbber
public static LinkedList list=new LinkedList();
NGD2z.
/** Creates a new instance of CountCache */ 5oy MR_yl
public CountCache() {} xI),0db
public static void add(CountBean cb){ 03jBN2[!
if(cb!=null){ 5|={1Lp24g
list.add(cb); V\8
5
} %cif0Td
} 'cc4Y~0s
} +}Wo=R}
aV%rq9Tp
CountControl.java *LQY6=H
L6}x3
/* ?mUu(D:7D
* CountThread.java Uwil*Jh
* w)>z3Lm
* Created on 2007年1月1日, 下午4:57 ?)<XuMh
* xb_:9
* To change this template, choose Tools | Options and locate the template under 31\^9w__8
* the Source Creation and Management node. Right-click the template and choose
gMMd=
* Open. You can then make changes to the template in the Source Editor. @+vTGjHA
*/ VNot4 62L
1:Gd{z
package com.tot.count; %* ;
8m'
import tot.db.DBUtils; c|a|z}(/J
import java.sql.*; hWe}(Ks
/** L#N.pd
* 90v18k
* @author O
lIH0
*/ cf3c+.o
public class CountControl{ f__WnW5h
private static long lastExecuteTime=0;//上次更新时间 r1?FH2Ns
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,H1~_|)<
/** Creates a new instance of CountThread */ dNt|"9~&
public CountControl() {} _cs9R%
public synchronized void executeUpdate(){ [|Pe'?zkf
Connection conn=null; W,J,h6{F
PreparedStatement ps=null; b:&$x (|
try{ V1U[p3J-S
conn = DBUtils.getConnection(); p&27|1pZm
conn.setAutoCommit(false); ?b$zuJ]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); BC[d={_-
for(int i=0;i<CountCache.list.size();i++){ pU'sADC
CountBean cb=(CountBean)CountCache.list.getFirst(); ^( VB5p
CountCache.list.removeFirst(); T+"y8#:
ps.setInt(1, cb.getCountId()); EqluxD=
ps.executeUpdate();⑴ T#f@8 -XUE
//ps.addBatch();⑵ nU *fne?
} `3n*4Lz
//int [] counts = ps.executeBatch();⑶ G* 6<pp
conn.commit(); K9Fnb6J$u
}catch(Exception e){ LK5H~FK
e.printStackTrace(); a][Z;g
} finally{ QYGxr+D
try{ *s4!;2ZhsU
if(ps!=null) { mf'1.{
ps.clearParameters(); Jjq%cA
ps.close(); I]$d,N!.
ps=null; zPc;[uHT
} vw;
}catch(SQLException e){} >u2#<k]1&
DBUtils.closeConnection(conn); YTit=4|
} _x{x#d;L3
} +yI^<BH
public long getLast(){ kl9z;(6p
return lastExecuteTime; k| o,gcU
} ![tI(TPq
public void run(){ @>j \~<%
long now = System.currentTimeMillis(); c[7qnSH
if ((now - lastExecuteTime) > executeSep) { dVfDS-v!
//System.out.print("lastExecuteTime:"+lastExecuteTime); g_X7@Dt
//System.out.print(" now:"+now+"\n"); h)`vc#"65k
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); `:4cb$
lastExecuteTime=now; ijYLf.R<
executeUpdate(); }(''|z#UE
} \ChcJth@o<
else{ Y'h'8
\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0/]vmDr
} ?O?~|nI
} bm.H0rHR4
} QD~`UJe>
//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 'b,D;'v
c y$$}
类写好了,下面是在JSP中如下调用。 r&DK> H
|i8dI )b
<% \&90$>h
CountBean cb=new CountBean(); 'wt|buu-H
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); lhTbg M
CountCache.add(cb); _F EF+I
out.print(CountCache.list.size()+"<br>"); uSjMqfK
CountControl c=new CountControl(); X_F= ;XF/
c.run(); mY(
_-[W
out.print(CountCache.list.size()+"<br>"); ]H[\~J
%>