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: JjnWv7W3$
R)'[Tt`# R
CountBean.java N`NW*~
v6O5n(5,,
/* 'rSJ9Mw"x
* CountData.java [k
* h:{^&d
a
* Created on 2007年1月1日, 下午4:44 _TjRvILC
* G!g];7PG(
* To change this template, choose Tools | Options and locate the template under `_ )5K u}
* the Source Creation and Management node. Right-click the template and choose I4MZJAYk
* Open. You can then make changes to the template in the Source Editor. !'8jy_<9
*/ Z>J3DH
SfUbjs@a
package com.tot.count; @~`:sa+H
0 1:(QJ
/** e+Sq&H!@
* p%- m"u
* @author )*Rr5l /l
*/ ivJTE
public class CountBean { VMJK9|JC[
private String countType; yI. hN
int countId; Nuc2CB)J
/** Creates a new instance of CountData */ UOkVU*{
public CountBean() {} o3a%u(
public void setCountType(String countTypes){ a_k~z3wG
this.countType=countTypes; ?HP{>l0r
} Zxn>]Z_
public void setCountId(int countIds){ 7nk3^$|
this.countId=countIds; j:xm>X'
} t9[%o=N~lD
public String getCountType(){ \_AoG8B
return countType; DUyUA'*4n|
} n[
public int getCountId(){ X{;5jnpG
return countId; CzG/=#IU
} (]sk3
A
} R/kfbV-b
AJ)N?s-=
CountCache.java 'Jl3%axR
C &&33L
/* D<(VP{,G
* CountCache.java JJu}Ed_
* (zIF2qY
* Created on 2007年1月1日, 下午5:01 ]QmY`pTB`
* Jb]22]
* To change this template, choose Tools | Options and locate the template under *KDwl<^A
* the Source Creation and Management node. Right-click the template and choose ]vq=~x
* Open. You can then make changes to the template in the Source Editor. '2v$xOh!y
*/ (V#*}eGy
tq2TiXo%
package com.tot.count; -59;Zn/
import java.util.*; !-s 6B
/** uEDvdd#V.
* >(eR0.x
* @author [_zoJ
*/ o`7B@]
public class CountCache {
W>m#Mz
public static LinkedList list=new LinkedList(); HQ`A.E2
/** Creates a new instance of CountCache */ `lN
Z|U
public CountCache() {} f^ 6da6Z
public static void add(CountBean cb){ );L +)UV
if(cb!=null){ ^LAdN8Cbb
list.add(cb); 4/E>k <MA
} !E9A=u{
} jQY^[A
} 4L)Ox;6>
!k=~a]
CountControl.java -ZBSkyMGy
W Z^u%Z
/* <(B: "wI
* CountThread.java f%c-
* "Sd2VSLg
* Created on 2007年1月1日, 下午4:57 @rxfOc0J#
* r9$7P?zm
* To change this template, choose Tools | Options and locate the template under 1zc-$B`t
* the Source Creation and Management node. Right-click the template and choose m'5rzZP
* Open. You can then make changes to the template in the Source Editor. JbW!V Y
*/ .$s=E8fW
x<h-F
package com.tot.count; O%rt7qV"g2
import tot.db.DBUtils; Tg/rV5@ka
import java.sql.*; J_>nn
/** 5MS5 Q]/
* {y==8fCJ
* @author z|sR
`]K
*/ Fn*)!,)
public class CountControl{ &-4SA j
private static long lastExecuteTime=0;//上次更新时间 h"ko4b3^'@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ?8R
/** Creates a new instance of CountThread */ G,A;`:/
public CountControl() {} LJmRa
public synchronized void executeUpdate(){ IC@-`S#F
Connection conn=null; >y^zagC*
PreparedStatement ps=null; ,v>|Ub,
try{ 1}b1RKKj<
conn = DBUtils.getConnection(); ]|)M /U *
conn.setAutoCommit(false); BZ>,Qh!J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); VU(#5X%Pn
for(int i=0;i<CountCache.list.size();i++){ hwdZP=X
CountBean cb=(CountBean)CountCache.list.getFirst(); KfMaVU=4P
CountCache.list.removeFirst(); >;OwBzB
ps.setInt(1, cb.getCountId()); pQOT\- bD
ps.executeUpdate();⑴ hPgDK.R'
//ps.addBatch();⑵ _-bEnF+/0
} jGKas I`
//int [] counts = ps.executeBatch();⑶ 6'QlC+E
conn.commit(); j[\aGS7u
}catch(Exception e){ !UW{xHu
e.printStackTrace(); Y<9Lqc.i
} finally{ 4z^5|$?_ta
try{ xgv&M:%D-
if(ps!=null) { h6C:`0o
ps.clearParameters();
Kgu#Mi~
ps.close(); -
]Mp<Y
ps=null; iXFN|ml
} 7P7d[KP<
}catch(SQLException e){} AcxC$uh
DBUtils.closeConnection(conn); ro*$OLc/
} O7GJg;>?
} L4H5#?'
public long getLast(){ 8cv [|`<
return lastExecuteTime; ?ZlN$h^
} CAV
Q[r5y
public void run(){
*"K7<S[
long now = System.currentTimeMillis(); 'Z ,T,zW
if ((now - lastExecuteTime) > executeSep) { g;PZ$|%&s>
//System.out.print("lastExecuteTime:"+lastExecuteTime); BSbi.@@tp
//System.out.print(" now:"+now+"\n"); T1c.ER}17
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C4/p5J
lastExecuteTime=now; 34Z$a{
w
executeUpdate(); 5W~-|8m
} \' ;zD-MX
else{ GJIM^
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 0I
\l_St@
} TNK~ETE4
} o? {rPFR
} 0xe*\CAo
//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 kmfxk/F}
5Bog\m S
类写好了,下面是在JSP中如下调用。 r-k,4Yz
b_xGCBC
<% /|z_z%=
CountBean cb=new CountBean(); nPo YjQi
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E<
Ini'od[
CountCache.add(cb); MuCnBx
out.print(CountCache.list.size()+"<br>"); 9q|36CAO_
CountControl c=new CountControl(); @E@5/N6M
c.run(); j,i>
1|J
out.print(CountCache.list.size()+"<br>");
{]=oOy1
%>