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: F3|pS:
`}Zbfe~
CountBean.java 6f9<&dCK
K[yJu 4
/* _eeX]xSSl
* CountData.java v2=!*
* [?6D1b[
* Created on 2007年1月1日, 下午4:44 yacGJz^f=
* W]MJ!4
* To change this template, choose Tools | Options and locate the template under .wOLi Ms
* the Source Creation and Management node. Right-click the template and choose &>B>+}'
* Open. You can then make changes to the template in the Source Editor. V~"d`j
*/ f]65iE?x
/;m!>{({)
package com.tot.count; >w# 3fTJ
.vF<3p|
/** ]=VI"v<X
* 9s6lt#?b
* @author [|O6n"'
*/ {+mkXp])R
public class CountBean { \@"
.
GM%
private String countType; XFAt\g
int countId; -"fq34v
/** Creates a new instance of CountData */ YHtI%
public CountBean() {} 2l4 i-;
public void setCountType(String countTypes){ BFu9KS+@)
this.countType=countTypes; yk6UuI^/
} p<['FRf"
public void setCountId(int countIds){ 8=AKOOU7>
this.countId=countIds; Z"KuS
} MpvA--
public String getCountType(){ U4pvQE.m<
return countType; <
l ^ Z;.
} l q9h Dn[p
public int getCountId(){ }H^^v[4
return countId; ^K[tO54
} q)i(wEdUZ
} y9 '3vZ
+~]g&Mf6o
CountCache.java /k Vc7LC
R6.#gb8^oS
/* 5E(P,!-.
* CountCache.java L%Hm#eFx
* j2n@8sCSO
* Created on 2007年1月1日, 下午5:01 IKpx~
* X*):N]
* To change this template, choose Tools | Options and locate the template under _(
Cp
* the Source Creation and Management node. Right-click the template and choose ->{WO+6(
* Open. You can then make changes to the template in the Source Editor. CU&,Kq@
*/ "7/YhLq7
+:Zi(SuS]
package com.tot.count; _9
O'
import java.util.*; %/C[\wp81
/** Ro$XbU)
* Lj,%pz J
* @author #<3\}*/
*/ 4 l(o{{
public class CountCache { LvdMx]*SSr
public static LinkedList list=new LinkedList(); j(2T,WM
/** Creates a new instance of CountCache */ e:R[
public CountCache() {} c:T P7"vG
public static void add(CountBean cb){ aoX$,~oI5
if(cb!=null){ x{5*%}lX8
list.add(cb); SQx):L)P6
} gC- 0je
} s:H1v&t,<
} G8'3.;"W5
Lo4t:H&
CountControl.java w:v:znQrW
%9M49s
/* ,Fiiw
* CountThread.java ;wZ.p"T9^
* IgJC>;]u
* Created on 2007年1月1日, 下午4:57 GK+w1%6)
* O:)@J b2
* To change this template, choose Tools | Options and locate the template under 9b6h!(
* the Source Creation and Management node. Right-click the template and choose RPwSo.c4
* Open. You can then make changes to the template in the Source Editor. !}?]&[N=
*/ ]ghPbS@
s5e}X:
package com.tot.count; 0jH2.d=
import tot.db.DBUtils; f5Oh#
import java.sql.*; jT',+
/** P])O\<)J
* j*}xe'#
* @author $-73}[UA 4
*/ {rQ`#?J}^?
public class CountControl{ 9"TPDU7"
private static long lastExecuteTime=0;//上次更新时间 |.5d ^z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Dlp::U*N'
/** Creates a new instance of CountThread */ M*%Z5,Tc
public CountControl() {} *d 4D9(
public synchronized void executeUpdate(){ mDUS9>
Connection conn=null; yFjSvm6
PreparedStatement ps=null; r>\.b{wI
try{ A[MEtI=Q J
conn = DBUtils.getConnection(); |EunDb[Y
conn.setAutoCommit(false); }dCnFZ{K3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); '1<QK
for(int i=0;i<CountCache.list.size();i++){ }J1#UH_E
CountBean cb=(CountBean)CountCache.list.getFirst(); ]h6<o*
CountCache.list.removeFirst(); tEl_A"^e
ps.setInt(1, cb.getCountId()); }<p%PyM
ps.executeUpdate();⑴ I]58;|J
//ps.addBatch();⑵ L 'y+^L|X
} %o>1$f]
//int [] counts = ps.executeBatch();⑶ q_bB/
conn.commit(); E),T,
}catch(Exception e){ `fXcW)
e.printStackTrace(); rE
8-MB
} finally{ Rd/!CJ@g
try{ lf 3W:0K
if(ps!=null) {
Ox RzKT
ps.clearParameters(); 2\n6XAQ*
ps.close(); qW*)]s)z
ps=null; f|!zjX`
} 7-)KTBFL
}catch(SQLException e){} ~<-i7uM
DBUtils.closeConnection(conn); Gwe9<
y
} zK v}J
} }/|1"D
public long getLast(){ rnUe/HjH
return lastExecuteTime; :B
im`mHl
} \TjsXy=:)
public void run(){ P$Nwf,d2u
long now = System.currentTimeMillis(); 8I%1
`V
if ((now - lastExecuteTime) > executeSep) { hz!.|U@,{<
//System.out.print("lastExecuteTime:"+lastExecuteTime); _F3 :j9^
//System.out.print(" now:"+now+"\n"); G9;WO*
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); kN)P-![
lastExecuteTime=now; 8Pq|jK "
executeUpdate(); c;VW>&,B
} Onao'sjY
else{ +m_quQ/ys
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); $|AxQQ%f
} h8Gp>b
} "\30YO>\
} p4=^
UP
//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 ;TYkJH"
o}BaZ|iZ2
类写好了,下面是在JSP中如下调用。 OvkY zI`
yfj<P/aA+
<% u7K0m!
jW
CountBean cb=new CountBean(); rRxqV?>n!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ebf0;1!
CountCache.add(cb); qbjRw!2?w
out.print(CountCache.list.size()+"<br>"); C
7v
8
CountControl c=new CountControl(); }0:=)e
c.run(); !^w+<p
out.print(CountCache.list.size()+"<br>"); `3~w#?+=*
%>