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: I%b:Z
<7-,`
CountBean.java =28H^rK{
TKBK3N
/* 2yO)}g FJ
* CountData.java HNUR6H&Fta
* \ui~n:aWJ
* Created on 2007年1月1日, 下午4:44 :a!a
* @DC2ci
>
* To change this template, choose Tools | Options and locate the template under h|uP=0
* the Source Creation and Management node. Right-click the template and choose e^Wv*OD'
* Open. You can then make changes to the template in the Source Editor. .O-DVW Cm
*/ xjk|O;ak
S^`9[$KH0
package com.tot.count; Ty|c@X
U)=Z&($T
/** h)RM9813<
* H_f2:Za
* @author }fMFQA)
*/ dv}R]f'
public class CountBean { O|TwG:!
private String countType; ; Kb[UZ1
int countId; tsC|R~wW
/** Creates a new instance of CountData */ Tq; "_s
public CountBean() {} v%~ViOgL\
public void setCountType(String countTypes){ |nZB/YZt
this.countType=countTypes; 5*za]
} MC)W?
public void setCountId(int countIds){ J0mCWtx&
this.countId=countIds; n.UM+2G
} >#n-4NZ;p9
public String getCountType(){ ZO6bG$y64
return countType; G:ngio]G0
} b%t9a\ 0V
public int getCountId(){ E_uH'E
return countId; @!NHeH=pR
} e[&3K<
} MW@b;=(
>b](v)
CountCache.java =0fx6V
OL"5A18;M
/* <l/Qf[V
* CountCache.java s/0FSv
x
* oOSyOD
* Created on 2007年1月1日, 下午5:01 }'v?Qq
* X1qj
l_A
* To change this template, choose Tools | Options and locate the template under N ^`Efpvg
* the Source Creation and Management node. Right-click the template and choose ,lYU#Hx*
* Open. You can then make changes to the template in the Source Editor. &L`p4AZ
*/ y'wW2U/1-
KCT"a:\
package com.tot.count; "A`'~]/hE
import java.util.*; :%]R x&08
/** Xn'>k[}<k
* 19`0)pzZ*P
* @author JN-8\L
*/ U*h)nc
public class CountCache { \eN/fTPm
public static LinkedList list=new LinkedList(); 0DT2qM[,
/** Creates a new instance of CountCache */ 1vudT&
public CountCache() {} <$6E r
public static void add(CountBean cb){ FdHWF|D
if(cb!=null){ _u5U> w
list.add(cb); .JKaC>oX
} +N&(lj
} /`@>v$oo
} Fpwh.R:yV
TL:RB)- <
CountControl.java h;[Ncj]
T=Q{K|JE
/* ,IATJs$E
* CountThread.java hd%F7D5
* )`7h,w
J[1
* Created on 2007年1月1日, 下午4:57 5R
G5uH/-<
* dj**,*s
* To change this template, choose Tools | Options and locate the template under ]>T/Gl1
* the Source Creation and Management node. Right-click the template and choose (2)9TpE;
* Open. You can then make changes to the template in the Source Editor. )
hB*Hjh
*/ <L#r6y~H
t4f\0`jN
package com.tot.count; VO?NrKyeW
import tot.db.DBUtils; :?W:'% (`[
import java.sql.*; "evV/Fg(
/** 5LH ]B
* >9|+F[Fc
* @author )Q?[_<1Y+
*/ D$
z!wV
public class CountControl{ C}E
ea~
private static long lastExecuteTime=0;//上次更新时间 \
.s".aA
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 X/7 49"23
/** Creates a new instance of CountThread */ 7s3<}
public CountControl() {} Nuq/_x
public synchronized void executeUpdate(){ W)O'( D
Connection conn=null; 6E4 L4Vb
PreparedStatement ps=null; L]")TQ
try{ 4`]1W,t
conn = DBUtils.getConnection(); `"4EE}eQc
conn.setAutoCommit(false); AOUO',v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); "ET"dMxU
for(int i=0;i<CountCache.list.size();i++){ #JM*QVzv
CountBean cb=(CountBean)CountCache.list.getFirst(); >@iV!!
CountCache.list.removeFirst(); biK.HL\V
ps.setInt(1, cb.getCountId());
&|*|
ps.executeUpdate();⑴ (Cd`~*5
//ps.addBatch();⑵ ,r4af<
} a@1gMZc*
//int [] counts = ps.executeBatch();⑶ `rQl{$9IC
conn.commit(); \C|06Bs$
}catch(Exception e){ e0 EJ[bG
e.printStackTrace(); r6G)R+ #
} finally{ ~=*_I4,+r
try{ IQ8AsV&'C
if(ps!=null) { /9Xf[<
ps.clearParameters(); (#k#0T kE
ps.close(); (^\i(cfu6Q
ps=null; 0l*/_;wo
} MLX.MUS
}catch(SQLException e){} +M:Q!'
DBUtils.closeConnection(conn); |05LHwb>
} K)OlCpHc
} %Kp}Wo6
public long getLast(){ (FHh,y~v
return lastExecuteTime; k/O&,T77}J
}
!^\/
1^
public void run(){ krU2S-
long now = System.currentTimeMillis(); eyV904<F
if ((now - lastExecuteTime) > executeSep) { .jw)e!<\N
//System.out.print("lastExecuteTime:"+lastExecuteTime); =Y0m;-1M
//System.out.print(" now:"+now+"\n"); MvFXVCT#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RR|Eqm3)
lastExecuteTime=now; i|Wn*~yFOO
executeUpdate(); RJM(+5xQ|
} /2 N%Z
else{ 5Tq 3L[T5;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); &h-1Z}
} kEh# 0
} H++rwVwj#h
} !5-[kG&
//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 V>Cf
8>m
LX'US-B.!
类写好了,下面是在JSP中如下调用。 $'Z!Y;Ue
tB.9Ov*
<% Ygb#U'|
CountBean cb=new CountBean(); Z(P#]jI]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nFSa~M
CountCache.add(cb); G$b4`wt
out.print(CountCache.list.size()+"<br>"); G <q@K-
CountControl c=new CountControl(); hyp`6?f
c.run(); N8TO"`wdbs
out.print(CountCache.list.size()+"<br>"); K(^x)w r-:
%>