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: Ni-@El99
wOs t).
CountBean.java #8qhl
U/9_:
/* \*5${[
* CountData.java 8t
>nL
* bE>"DPq
* Created on 2007年1月1日, 下午4:44 :pvJpu$]
* 9B?-&t
* To change this template, choose Tools | Options and locate the template under .I
nDyKt
* the Source Creation and Management node. Right-click the template and choose _%:$sAj
* Open. You can then make changes to the template in the Source Editor. M#;"7Qg
*/ `D={l29H
b,uudtlH
package com.tot.count; i-gN<8\v
=WM^i86
/** 6-J%Z%yT #
* 6g&Ev'
* @author u@pimRVo
*/ g}n-H4LI
public class CountBean { db`L0JB
private String countType; XsbYWJdds
int countId;
`A ^
/** Creates a new instance of CountData */ ME.a * v
public CountBean() {} 6,a:s:$>}R
public void setCountType(String countTypes){ +Fa!<txn
this.countType=countTypes; JK'FJ}Z4
} l~Rd\.O
public void setCountId(int countIds){ yr/G1?k%ML
this.countId=countIds; S^T
><C
} ]-"G:r
public String getCountType(){ f O ,5
u;
return countType; 7oV$TAAf
} P+bA>lJd
public int getCountId(){ !!?TkVyEyM
return countId; ~EtwX YkRZ
} x>$e*
} ]+A%37
B"?ivxM:U
CountCache.java +o-jMvK9
7]H<ou
/* cB=ExD.Q
* CountCache.java b|oT!s
* #gsJ
tT9
* Created on 2007年1月1日, 下午5:01 cPy/}A
* "."ow|
* To change this template, choose Tools | Options and locate the template under |wINb~trz
* the Source Creation and Management node. Right-click the template and choose qV79bK
* Open. You can then make changes to the template in the Source Editor. y~n1S~5cI
*/ xM)6'= x6
O+OUcMa,
package com.tot.count; R9\ )a2
import java.util.*; ^:~!@$*;6
/** 5y8VA4L/o
* c*.-mS~Z`
* @author @L$!hTaP
*/ dVe,;?+A
public class CountCache { Q>(a JF
public static LinkedList list=new LinkedList(); QtQbr*q@%
/** Creates a new instance of CountCache */ =}zSj64
public CountCache() {} OXJ'-EZH
public static void add(CountBean cb){ 0p]v#z}
if(cb!=null){ @2g
<d
list.add(cb); hjD%=Ri0Z
} gVNoC-n)
} F.),|t$\
} ;2 P
}`.d4mm
CountControl.java &EmG\vfE
{B-*w%}HU
/* IGNU_w4j
* CountThread.java )$ M2+_c
* LhRd0
* Created on 2007年1月1日, 下午4:57 LwYWgT\e
* :g ~_
* To change this template, choose Tools | Options and locate the template under 3 3zE5vr
* the Source Creation and Management node. Right-click the template and choose h:RP/0E
* Open. You can then make changes to the template in the Source Editor. }i{A4f`
*/ TJCE6QG
LUdXAi"f
package com.tot.count; LXqPNVp#
import tot.db.DBUtils; s'|t2`K("
import java.sql.*; H*e +
2
/** UmR4zGM}
* F3hG8YX
* @author #%EHcgF
*/ +PS
jBO4!
public class CountControl{ ``%yVVg}
private static long lastExecuteTime=0;//上次更新时间 XBoq/kbw!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 .,20_<j%=
/** Creates a new instance of CountThread */ m*jTvn
public CountControl() {} 4*&k~0#t
public synchronized void executeUpdate(){ pH3<QNq5
Connection conn=null; F$bV}>-1k
PreparedStatement ps=null; tzthc*-<
try{ stUUez>
conn = DBUtils.getConnection(); Ss%1{s~ok
conn.setAutoCommit(false); v&bG`\ !
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G[1\5dK*uR
for(int i=0;i<CountCache.list.size();i++){ /'VbV8%
CountBean cb=(CountBean)CountCache.list.getFirst(); 0( *L)s,5
CountCache.list.removeFirst(); f7y.##W G
ps.setInt(1, cb.getCountId()); j+@3.^vK
ps.executeUpdate();⑴ AJm$(3?/D
//ps.addBatch();⑵ tv26eK
38
} ,J8n}7aI
//int [] counts = ps.executeBatch();⑶ ^qnmKA>"F
conn.commit(); L$BV`JWPw
}catch(Exception e){ "Kdn`zN{
e.printStackTrace(); G;$;$gM
} finally{ 'qvj[lpGr
try{ K|YB)y
if(ps!=null) { _ OC@J*4.
ps.clearParameters(); BlQX$s]
ps.close(); ^Kg n:l
ps=null; fjOq@thD
} 2;u
i'B
}catch(SQLException e){} aydNSgu
DBUtils.closeConnection(conn); ^H&U_
} >
K?OsvX
} k%FA:ms|k
public long getLast(){ GX0zirz
return lastExecuteTime; n}j6gN! O
} 9!
/kyyU
public void run(){ a{.q/Tbt
long now = System.currentTimeMillis(); px"H
if ((now - lastExecuteTime) > executeSep) { X\/M(byn
//System.out.print("lastExecuteTime:"+lastExecuteTime); #-@uLc
//System.out.print(" now:"+now+"\n"); .p, VZ9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 6y~F'/ww
lastExecuteTime=now; 4e Y?#8
executeUpdate(); !nCq8~#
} N-]/MB8
else{ W"^ =RY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5|nc^
12
} <l$ d>,
} X.#)CB0c1Q
} P6R_W
//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 RFyMRE!?
y;uR@{
类写好了,下面是在JSP中如下调用。 31@Lr[!
t2s/zxt
<% 10i$ b<O
CountBean cb=new CountBean(); o$buoGSPc
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); q+y\pdhdO
CountCache.add(cb); &'x~<rx
out.print(CountCache.list.size()+"<br>"); [d8Q AO1;)
CountControl c=new CountControl(); -~|{q)!F
c.run(); c#sHnpP
out.print(CountCache.list.size()+"<br>"); YT
Zi[/
%>