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: z-BXd
~Uj=^leYO
CountBean.java |<HPn4
,X
wYdb*"R
/* QFE:tBHe
* CountData.java kh!FR u h
* vhe>)h*B
* Created on 2007年1月1日, 下午4:44 7z/|\D_{
* w+C7BPV&
* To change this template, choose Tools | Options and locate the template under O $LfuL
* the Source Creation and Management node. Right-click the template and choose rr+|Zt
Y
* Open. You can then make changes to the template in the Source Editor. V n7*JS
*/ vV6<^W:9F
5rwu!Y;7*
package com.tot.count; -]L6=
v;BV@E0}x
/** 0[A[U_b
* t=rEt>n~L
* @author mkMq
*/ yu;+o3WlK
public class CountBean { t!* ?dr
private String countType; `
w=>I
int countId; cT<1V!L4
/** Creates a new instance of CountData */ %huRsQ%}
public CountBean() {} ?iPC*
public void setCountType(String countTypes){ I*%-cA%l
this.countType=countTypes; WgR).Yx
} ,f<?;z
public void setCountId(int countIds){ vmi+_]
this.countId=countIds; bT\1>
} 4<9=5 q]
public String getCountType(){ BYpG
return countType; p
s/Ayjk
} 7OC#8,
public int getCountId(){ jDKO}
bQ
return countId; W_||6LbZy
} a!ud{Dx
} 4Z1ST;
vY4\59]P
CountCache.java %WSo b@f8
s&A}
h
/* BD68$y
* CountCache.java @"hb) 8ng
* nePfuG]Q
* Created on 2007年1月1日, 下午5:01 N<|@ymi
* kEJj=wx
* To change this template, choose Tools | Options and locate the template under Mxe}B'
* the Source Creation and Management node. Right-click the template and choose 5G::wuxk
* Open. You can then make changes to the template in the Source Editor. S-P/+K6
*/ YT8vP~
5}:-h>
package com.tot.count; ?u-|>N>
import java.util.*; fo5iJz"Z
/** hq%?=2'9?
* %+f>2U4I
* @author >,TUZ
*/ V:qSy#e
public class CountCache { vBRQp&YwX
public static LinkedList list=new LinkedList(); J3,fk)
/** Creates a new instance of CountCache */ n\QgOSr<
public CountCache() {} |h- QP#]/
public static void add(CountBean cb){ 0Z~p%C<LW
if(cb!=null){ Z?}dq-Vh&
list.add(cb); 0vFD3}~>
} Hx#;Z
} Hcl(3>Jn2
} K$>%e36Cc
5Ec6),+&
CountControl.java {F3xJ[
prYs
$j
/* &{ay=Mj
* CountThread.java 5XO;N s
* T29Dt
* Created on 2007年1月1日, 下午4:57 YX=a#%vrl
* @GkILFN
* To change this template, choose Tools | Options and locate the template under ?
K;dp
* the Source Creation and Management node. Right-click the template and choose sA/pVU
* Open. You can then make changes to the template in the Source Editor. <<@bl@9'
*/ 5Eg1Q
YVt
1|RANy
package com.tot.count; =5Q]m6-SgV
import tot.db.DBUtils; EwuO&q
import java.sql.*; >XK
PTC5H
/** d^RxQuA
* IHe/xQ@
* @author /~}}"zx&
*/ `Zf^E
>)
public class CountControl{ 1HXjN~XF
private static long lastExecuteTime=0;//上次更新时间 DAS/43\
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 J]v%q,"
/** Creates a new instance of CountThread */ aIJt0;
public CountControl() {} ~5_Ad\n9
public synchronized void executeUpdate(){ u6T+Cg
Connection conn=null; 18~>ZR
PreparedStatement ps=null; (}a8"]Z
try{ qLw{?sH}J/
conn = DBUtils.getConnection(); #i@;J]x(
conn.setAutoCommit(false); _]yn"p
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HIQ_%L4]
for(int i=0;i<CountCache.list.size();i++){ 0KYEb%44
CountBean cb=(CountBean)CountCache.list.getFirst(); 8C[C{qOJ
CountCache.list.removeFirst(); nTuJEFn{
ps.setInt(1, cb.getCountId()); }'""(,2
ps.executeUpdate();⑴ ,-izEr
//ps.addBatch();⑵ D&/kCi= R
} k,'L}SK
//int [] counts = ps.executeBatch();⑶ ' qWALu
conn.commit(); m5L-67[sB
}catch(Exception e){ W{%TlN
e.printStackTrace(); )\_:{ c
} finally{ f%Ns[S~ r
try{ n1JRDw"e$$
if(ps!=null) { hn^<;av=
ps.clearParameters(); ZYI{i?Te#
ps.close(); >xF/Pl
ps=null; #N#'5w-G
} 0*rQ3Z
}catch(SQLException e){} .$Ik`[+Z
DBUtils.closeConnection(conn); (&}i`}v_
} \]%6|V
} qDv93
public long getLast(){ 9F4Dm*_<
return lastExecuteTime; sArhZ[H
} Y<mej][
public void run(){ E}Y!O"CAV
long now = System.currentTimeMillis(); )f}YW/'
if ((now - lastExecuteTime) > executeSep) { "B=
//System.out.print("lastExecuteTime:"+lastExecuteTime); }!;s.[y
//System.out.print(" now:"+now+"\n"); ?3%`bY+3;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :z4)5=
6M
lastExecuteTime=now; q<\,
executeUpdate(); 3AQZRul
} [onGNq?#
else{ lp<g\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); vV[eWd.o6M
} Av"R[)
} "$N#p5
} ;u;# g
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 L{hnU7sY
VTG9$rQZ
类写好了,下面是在JSP中如下调用。 n;(\5{a
K%"5ImM
<% k *Q<3@S
CountBean cb=new CountBean(); YQ39A_e
g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); l%?T2Fm3>
CountCache.add(cb); @\0Eu212
out.print(CountCache.list.size()+"<br>"); 99}(~B
CountControl c=new CountControl(); ?0)&U
c.run(); ?**+e%$$
out.print(CountCache.list.size()+"<br>"); ? i( %
%>