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: ye?4^@u u
&ed&2t`Y
CountBean.java q+<<Ku(20
n/]w!
/* $FR1^|P/G
* CountData.java Jzu U
k
* TEB<ia3+
* Created on 2007年1月1日, 下午4:44 bzj9U>eY
* cl2+,!:
* To change this template, choose Tools | Options and locate the template under n`v;S>aT
* the Source Creation and Management node. Right-click the template and choose a*
2*aH7
* Open. You can then make changes to the template in the Source Editor. j`H5S
*/ tFj[>_d7
(p6$Vgdt
package com.tot.count; [k<"@[8)
;&iZ{
/** .0ov>4,R
* ayGYVYi
* @author GTYCNi66
*/ Lvco9
Ak
public class CountBean { o4Ny9s
private String countType; HgVPyo
int countId; 4DLp+6zP
/** Creates a new instance of CountData */ skSs|slp
public CountBean() {} 3jeB\
public void setCountType(String countTypes){ Gz09#nFZk
this.countType=countTypes; C6<*'5T
} hKx*V"7/#\
public void setCountId(int countIds){ _.}1 Y,Q
this.countId=countIds; mE>v (JY
} 6I8A[
public String getCountType(){ ,q_'l?Pn
return countType; _U
Q|I|V#
} 1UHlA8w7Q
public int getCountId(){ S{uKm1a
return countId; &Y`V A
} 40?xu#"
} <q}w, XU
PJ$C$G
CountCache.java Uj/m
#saK8; tp
/* 27"M]17)
* CountCache.java @Yzdq\FI
* GF^)](xY+
* Created on 2007年1月1日, 下午5:01 E`A6GX
* sLHUQ(S!
* To change this template, choose Tools | Options and locate the template under *- S/{
.&
* the Source Creation and Management node. Right-click the template and choose !<EQVqj6
* Open. You can then make changes to the template in the Source Editor. pwIu;:O!?
*/ LvM;ZfAEv
0aWy!d
package com.tot.count; 3)ZdT{MY
import java.util.*; 1K&_t
/** N'5AU (
* O>vbAIu
* @author 7RpAsLH=
*/ 'B"A*!"b
public class CountCache { tJ qd
public static LinkedList list=new LinkedList(); AiDV4lHr
/** Creates a new instance of CountCache */ J$+K't5BZ
public CountCache() {} U??T>
public static void add(CountBean cb){ )NjxKSiU@
if(cb!=null){ FS+v YqwK
list.add(cb); ",O}{z
} p?Rq
} n1E^8[~'
} r.~^h^c]
L/+KY_b:*
CountControl.java s7
K](T4
B*
hW
/* q@@C|oqEX
* CountThread.java RJ63"F $
* [(81-j1v
* Created on 2007年1月1日, 下午4:57 .[Hv/?L
* H)@f_pfj(
* To change this template, choose Tools | Options and locate the template under g~/@`Z2Y
* the Source Creation and Management node. Right-click the template and choose $D%[}[2
* Open. You can then make changes to the template in the Source Editor. ,suC`)R
*/ s*3p*zf
rn8#nQ>QZ%
package com.tot.count; Nn:>c<[
import tot.db.DBUtils; :~PzTUz
import java.sql.*; x$gVEh*k
/** lFZ}.
* ~N!-4-~p
* @author WGC'k
s ^
*/ %~{G*%:
public class CountControl{ 3W#f
Fy
private static long lastExecuteTime=0;//上次更新时间 ",Ge:\TR=
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 uG:xd0X+W
/** Creates a new instance of CountThread */ l,w$!FnmR
public CountControl() {} 9$iDK$%
public synchronized void executeUpdate(){ $%GW~|S\C
Connection conn=null; p$+.]
PreparedStatement ps=null; naaww
try{ IPTEOA<M[
conn = DBUtils.getConnection(); q\I2lZ
conn.setAutoCommit(false); 9FKowF_8
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); PKK18E}{%^
for(int i=0;i<CountCache.list.size();i++){ jn:9Cr,o;g
CountBean cb=(CountBean)CountCache.list.getFirst(); qiyX{J7Z
CountCache.list.removeFirst(); J|gRG0O9Ya
ps.setInt(1, cb.getCountId()); }$wWX}@
ps.executeUpdate();⑴ >P_/a,O8
//ps.addBatch();⑵ [m+):q^
} $TK<~3`
//int [] counts = ps.executeBatch();⑶ ? 3'O
conn.commit(); "I
n[= 2w
}catch(Exception e){ ;5.S"
e.printStackTrace(); HuRq0/"
} finally{ wVMR&R<t
try{ /t$J<bU
if(ps!=null) { ch-.+p3
ps.clearParameters(); qVe&nXo
ps.close(); 0DQ\akh
ps=null; o
00(\ -eb
} K:_5#!*^98
}catch(SQLException e){} ~L55l2u7
DBUtils.closeConnection(conn); g/_j"Nn
} ^:Hx .
} g q`S`
public long getLast(){ ka UEv\T
return lastExecuteTime; &40# _>W7
} %@Ow.7zh
public void run(){ +T,Yf/^Fn
long now = System.currentTimeMillis(); aZBS!X
if ((now - lastExecuteTime) > executeSep) { n72+X
//System.out.print("lastExecuteTime:"+lastExecuteTime); x./l27}6
//System.out.print(" now:"+now+"\n"); J =j6rD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); !$1'q~sO
lastExecuteTime=now; 6!Z>^'6
executeUpdate(); p@Va`:RDW
} #J_+
SL[
else{ L2$`S'U W
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NAnccB D!{
} o)}M$}4
} -,Y[`(q
} f?P>P23
//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 \]7i-[
3Gyw^_{J
类写好了,下面是在JSP中如下调用。 KbicP<
,%!E-gr
<% L';b908r2
CountBean cb=new CountBean(); {<J(*K*\Jo
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); UU;U,q
CountCache.add(cb); AJWV#J%nB
out.print(CountCache.list.size()+"<br>"); QY}1i .f
CountControl c=new CountControl(); :u4q.^&!e
c.run(); a"Q> K7K
out.print(CountCache.list.size()+"<br>"); Kx<T;iJ}
%>