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: r%f Q$q>
Axsezr/
CountBean.java jKmjZz8L]%
# &.syD#
/* T"{~mQ*
* CountData.java FTCIfW
* */h(4Hz
* Created on 2007年1月1日, 下午4:44 3XlQ 4
* nrKAK^
* To change this template, choose Tools | Options and locate the template under 1"Oe*@`pV
* the Source Creation and Management node. Right-click the template and choose &Tt7VYJfIV
* Open. You can then make changes to the template in the Source Editor. -+@N/d5
*/ n#x_da-m]
g7]S
package com.tot.count; pYQSn.`V~
x
t-s"A
/** @/kI;8
* +@?Q "B5u}
* @author >`UqS`YQK
*/ m8F$h-
public class CountBean { Ag9GYm
private String countType; aeUgr!
int countId; 6d]4
%Q T
/** Creates a new instance of CountData */ HSNj
public CountBean() {} ;SU<T^a
public void setCountType(String countTypes){ ?h4[yp=w
this.countType=countTypes; LSc^3=X
} 8_!qoW@B
public void setCountId(int countIds){ Y^Buz<OiG
this.countId=countIds; ?I^$35
} h@R n)D
public String getCountType(){ 0]7jb_n1
return countType; 6Sd:5eTEQ
} ^$P_B-C N
public int getCountId(){ :G 5p`;hGo
return countId; ivgX o'=
} f?.VVlD
} KX~
uE6rX
.t\J@?Z
CountCache.java L;opQ~g
J.XkdGQ
/* ks.p)F>]
* CountCache.java _m?i$5
* .\oW@2,RA9
* Created on 2007年1月1日, 下午5:01 V]--d33/a
* U>*@VOgB
* To change this template, choose Tools | Options and locate the template under I*TTD]e'X
* the Source Creation and Management node. Right-click the template and choose \m|5Aqs
* Open. You can then make changes to the template in the Source Editor. dYISjk@
*/ it H
@I4HpY7:
package com.tot.count; mh"PA p
import java.util.*; 1oO(;--u_
/** ;U4O` pZ
* D,.`mX
* @author #WG}"[ ,c
*/ R-zS7Jyox
public class CountCache { ,Dv*<La`\
public static LinkedList list=new LinkedList(); \uHC 9}0
/** Creates a new instance of CountCache */ |Jx:#OM
public CountCache() {} l tNI+G
public static void add(CountBean cb){ W]Xwt'ABz
if(cb!=null){ %R4 \[e
list.add(cb); DtBvfYO8)>
} @Pc7$ qD %
} OiAuL:D
} $MDmY4\
GCYXDovh
CountControl.java |e#W;q$v
^!^M Gzu
/* -sv%A7i
* CountThread.java mxCneX
* *^@b0f~vj
* Created on 2007年1月1日, 下午4:57 >uZc#Zt
* 2gK]w$H7!
* To change this template, choose Tools | Options and locate the template under Me z&@{
* the Source Creation and Management node. Right-click the template and choose s2,6aW C
* Open. You can then make changes to the template in the Source Editor. D6lzcf
*/ !)oQ9,N
K@n-#
package com.tot.count; m#W XZr
import tot.db.DBUtils; ep3VJ"^
import java.sql.*; Yz2N(g[
/** =A,T:!}'
* S}Wj.l+F
* @author tOVTHx3E]
*/ wclj9&k
public class CountControl{ k+[oYd
private static long lastExecuteTime=0;//上次更新时间 J1(SL~e],
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ~c v|,
/** Creates a new instance of CountThread */ +vJ}'uR3P
public CountControl() {} }8 ;,2E*z
public synchronized void executeUpdate(){ H5d@TB,`
Connection conn=null; pFd{Tdh
PreparedStatement ps=null; 91R7Rrne
try{ vxf09v{-
conn = DBUtils.getConnection(); uDG>m7(}/h
conn.setAutoCommit(false); Fp?M@
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 38-kl,Vw
for(int i=0;i<CountCache.list.size();i++){ @>VX]Qe^X
CountBean cb=(CountBean)CountCache.list.getFirst(); 5I[:.o0
CountCache.list.removeFirst(); !lg_zAV
ps.setInt(1, cb.getCountId()); e%:vLE
9
ps.executeUpdate();⑴ |^Yz*r?BJ
//ps.addBatch();⑵ PSAEW.L
} .I|b9$V
//int [] counts = ps.executeBatch();⑶ vO?sHh
conn.commit(); Zt41f PQ
}catch(Exception e){ /kr|}`#
Z
e.printStackTrace(); [H!do$[>
} finally{ @P0rNO%y
try{ V G7#C@>Z
if(ps!=null) { vt"bB
ps.clearParameters(); bO$KV"*!
ps.close(); b"o\-iUioe
ps=null; I3.JAoB>!
} _0
43,
}catch(SQLException e){} ]Rf$&7`g{
DBUtils.closeConnection(conn); F&p42!"
} U43U2/^
} t^Bs3;E^
public long getLast(){ {TJ"O
return lastExecuteTime; TPx0LDk%(
} dL'oIBp
public void run(){ SefF Ci%4
long now = System.currentTimeMillis(); B:i$
if ((now - lastExecuteTime) > executeSep) { J s33S)
//System.out.print("lastExecuteTime:"+lastExecuteTime); i0\]^F
//System.out.print(" now:"+now+"\n"); rvhMu}.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZX-A}
lastExecuteTime=now; x/]G"?Uix
executeUpdate(); 6E^m*la%
} (oCpQDab@
else{ "<egm^Yq
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RI'}C`%v
} Z8h;3Ek
} I^LU*A=
} V`/c#y||
//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 |R91|-H
!}mM"|<
类写好了,下面是在JSP中如下调用。 &<&eKq
V?T&>s
<% m_ wvi
CountBean cb=new CountBean(); DV?c%z`YO
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _W Hi<,-
CountCache.add(cb); +Y+fM
out.print(CountCache.list.size()+"<br>"); m/g[9Y
CountControl c=new CountControl(); &-IkM%_A9
c.run(); S_AN.8T
out.print(CountCache.list.size()+"<br>"); rx#GrV*y
%>