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: (J[Xryub
#~!"`B?#*
CountBean.java `J1HQ!Z
E7t;p)x
/* 7i*eKC`ZqK
* CountData.java ; h\T7pwwb
* ;xZjt4M1
* Created on 2007年1月1日, 下午4:44 HcgvlFb
* =}vT>b
* To change this template, choose Tools | Options and locate the template under "|h%Uy?XY
* the Source Creation and Management node. Right-click the template and choose -
8p!,+Dk
* Open. You can then make changes to the template in the Source Editor. <%HRs>4
*/ z@yTkH_
[ n7>g
package com.tot.count; 7p{Pmq[
< cvh1~>(
/** 0V4B Q:v
* n:,mo} ?X
* @author &^r>Q`u
*/ OvtE)ul@
public class CountBean { DMM<,1
private String countType; f<NR6],}
int countId; .qgUD
/** Creates a new instance of CountData */ Zz0e4C
public CountBean() {} G18w3BFx
public void setCountType(String countTypes){ yd).}@
this.countType=countTypes; N%
4"9K
} 8.i4QaU
public void setCountId(int countIds){ uMJ\
this.countId=countIds; /]_ t->
} Ot2o=^Ng
public String getCountType(){ q.c)>=!.
return countType; Y !?'[t
} (k?HT'3)
public int getCountId(){ Mf1(4F
return countId; Ks-$:~?5":
} j,.\QwpU
} u=
NLR\
.\n` 4A1z
CountCache.java +n)n6}S
"2l`XH
/* $KK~KEZ2
* CountCache.java ,~1"50 Hp@
* d9K8[Q5^3
* Created on 2007年1月1日, 下午5:01 `gX@b^
* 1^!SuAA@
* To change this template, choose Tools | Options and locate the template under w G %W{T$
* the Source Creation and Management node. Right-click the template and choose ;V
xRaj?
* Open. You can then make changes to the template in the Source Editor. TmsIyDcD~
*/ cJ;Nh>ey
k, HC"?K
package com.tot.count; j*jUcD*
import java.util.*; DN*5q9.
/** s/E|Z1pg3
* AcC &Q:g
* @author yD7BZI
xW
*/ ieFl4hh[G
public class CountCache { 8]ZzO(=@{
public static LinkedList list=new LinkedList(); .T|
}rB<c
/** Creates a new instance of CountCache */ UEU/505
public CountCache() {} vADiW~^Q^
public static void add(CountBean cb){ #c^V%
if(cb!=null){ `*C=R
_
list.add(cb); ^[M{s(b
} gc9R;B1
} E>!=~ 7.
} Y`;}w}EcgR
F5h/>
CountControl.java @^P^-B
-8Jw_
/* CM;b_E)9)f
* CountThread.java Zw.8B0W
* o~Se[p
* Created on 2007年1月1日, 下午4:57 tyu@aCK
* ,NSf
* To change this template, choose Tools | Options and locate the template under Mo,&h?VOM?
* the Source Creation and Management node. Right-click the template and choose U1[)e D`
* Open. You can then make changes to the template in the Source Editor. /wV|;D^ )
*/ Cn{Hk)6
l":W@R
package com.tot.count; c3$T3Lu1
import tot.db.DBUtils; mj~:MCC
import java.sql.*; VdLoi\-/L
/** %rzPh<>e
* Dac)`/
* @author b 7UJ
*/ {>]\<
public class CountControl{ p3I"LY
private static long lastExecuteTime=0;//上次更新时间 &Y]':gJ
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +yGQt3U
/** Creates a new instance of CountThread */ d*gAL<M7E
public CountControl() {} TNX9Z)=>g
public synchronized void executeUpdate(){ |#oS7oV(
Connection conn=null; /*K2i5&X
PreparedStatement ps=null; !+l'<*8V
try{ =Zd(<&B K
conn = DBUtils.getConnection();
is'V%q
conn.setAutoCommit(false); _BczR:D*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); al2t\Iq90
for(int i=0;i<CountCache.list.size();i++){ MdHm%Vx
CountBean cb=(CountBean)CountCache.list.getFirst(); 8-q^.<9
CountCache.list.removeFirst(); Harg<l
ps.setInt(1, cb.getCountId()); }E'0vf/
ps.executeUpdate();⑴ t]/eCsR
//ps.addBatch();⑵ Nk|cU;?+
} j(;^XO Y#
//int [] counts = ps.executeBatch();⑶ O$Rz/&
conn.commit(); d9N[f>
}catch(Exception e){ ,eXtY}E
e.printStackTrace(); h>N}M}8
} finally{ 7=!9kk 0
try{ wPA^nZ^}9c
if(ps!=null) { __=H"UhWv
ps.clearParameters(); 64s;EC
ps.close(); AK:cDKBO
ps=null; o[|[xuTm
} 8bIP"!=*W
}catch(SQLException e){} i5,iJe0cA
DBUtils.closeConnection(conn); 5xQ-f
} >=~\b
} $ghZ<Y2}9
public long getLast(){ }3pM,.
return lastExecuteTime; @<.@X*#I
} NYm"I`5w
public void run(){ !`DRJ)h
long now = System.currentTimeMillis(); I \:WD"
if ((now - lastExecuteTime) > executeSep) { <`H0i*|Ued
//System.out.print("lastExecuteTime:"+lastExecuteTime); ll:UIxx
//System.out.print(" now:"+now+"\n"); ZnG.::&:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h^M_yz-f
lastExecuteTime=now;
bGRt
executeUpdate(); m,l/=M
} A1WUK=P
else{ F3tps
jQ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); gP^2GnjHL8
} Dg&84,bv^
} jLVJ+mu
} P3M$&::D-
//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 Fn4v/)*H
04a
^jjc
类写好了,下面是在JSP中如下调用。 f5jl$H.
Up9{aX
<% s#2t\}/
CountBean cb=new CountBean(); 'ofj1%c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); dzVi ~wt_&
CountCache.add(cb); U|^xr~q!f-
out.print(CountCache.list.size()+"<br>"); +-9vrEB
CountControl c=new CountControl(); )uPJ?
2S9
c.run(); mU'<:gL+
out.print(CountCache.list.size()+"<br>"); RNg?o[S
%>