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: )@c3##Zp)
fNEz
CountBean.java |E|T%i^}./
qP`?M\!O
/* XaGz].Sv
* CountData.java 3*\8p6G
* t~~r-V":
* Created on 2007年1月1日, 下午4:44 .jum "va%
* -4`sqv ]
* To change this template, choose Tools | Options and locate the template under QX/]gX
* the Source Creation and Management node. Right-click the template and choose r!M#7FDs(
* Open. You can then make changes to the template in the Source Editor. vz,LF=s2
*/ u~)%tL
ok=40B99T
package com.tot.count; ={xqNRVd
DJJZJ}7
/** YlB["@\[B
* 5@.zz"o.`
* @author 0hZxN2r
*/ >%i9 oI<)
public class CountBean { Dtt\~m;AR
private String countType; j@V$Mbv
int countId; $Q,n+ /
/** Creates a new instance of CountData */ n%U9iwJ.
public CountBean() {} UNY@w=]<
public void setCountType(String countTypes){ I~'gK8<e7
this.countType=countTypes; *p"O*zj
} _6J<YQK
public void setCountId(int countIds){ 9H8=eJd
this.countId=countIds; [Z% l.
} <mn-=#)
public String getCountType(){ &X7ttB"#h
return countType; vF+YgQ1H
} t*rp3BIG
public int getCountId(){ aKD;1|)
return countId; ^s.oZj
q
} @6[x%j/!bt
} l^BEFk;
?PYNE
CountCache.java V!}L<cN
u-1@~Z
/* ,iohfZz
* CountCache.java >T(M0Tkt
* !~tnti6
* Created on 2007年1月1日, 下午5:01 wz)m{:b<
* =yo=q)W
* To change this template, choose Tools | Options and locate the template under 4&H+hN{3
* the Source Creation and Management node. Right-click the template and choose kEx8+2s=M
* Open. You can then make changes to the template in the Source Editor. 0vcET(
*/ i~ROQMN1
% M+s{ l
package com.tot.count; pV_}Or_
import java.util.*; \4C)~T:*
/** lW&[mnR
* 6WCmp,*
* @author wbl${@4
*/ 8\P
JSr
public class CountCache { i:R!T,
public static LinkedList list=new LinkedList(); \S'cWB
/** Creates a new instance of CountCache */ oNrEIgaA(+
public CountCache() {} Ep,1}Dx
public static void add(CountBean cb){ %pd5w~VP
if(cb!=null){ ?#U0eb5u
list.add(cb); 0\QYf0o
} %d ZM9I0
} JPHUmv6
} E#8J+7
.!!79 6hS
CountControl.java iczs8gj*
z{@=_5;
/* A"`L~|&
* CountThread.java %~ ;nlDw
* kA1f[AL
* Created on 2007年1月1日, 下午4:57 '/n\Tg+
* Xk
5oybDI
* To change this template, choose Tools | Options and locate the template under Q1K"%
* the Source Creation and Management node. Right-click the template and choose B<rPvM7a
* Open. You can then make changes to the template in the Source Editor. rrW! X q
*/ `9]P/J^
'et(:}i
package com.tot.count; (tgEa{rPAP
import tot.db.DBUtils; WvIK=fdZ$
import java.sql.*; u_h=nk
/** #^"hqNwA
* a"MTQFm'
* @author
Cl%V^xTb
*/ yIM.j;5:~5
public class CountControl{ yl[2et
private static long lastExecuteTime=0;//上次更新时间 b;SFI^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >9<_s
^_
/** Creates a new instance of CountThread */ 6R0D3kW
public CountControl() {} }3bQ>whF
public synchronized void executeUpdate(){ YNuewD
Connection conn=null; 1VRqz5
PreparedStatement ps=null; ;D6x=v=2
try{ Vj#%B.#Zbf
conn = DBUtils.getConnection(); &8R-C[A
conn.setAutoCommit(false); ?S+/QyjcfJ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %?U"[F1
for(int i=0;i<CountCache.list.size();i++){ i.B$?cr~
CountBean cb=(CountBean)CountCache.list.getFirst(); :zRB)hd
CountCache.list.removeFirst(); c-?
Ygr
ps.setInt(1, cb.getCountId()); K'>P!R:El
ps.executeUpdate();⑴ l!xgtP K
//ps.addBatch();⑵ ,^UcRZ8.H
} bEBZ!ghU
//int [] counts = ps.executeBatch();⑶ h[vAU 9f)
conn.commit(); /<(R
}catch(Exception e){ k9.u[y.
e.printStackTrace(); 6nM
rO$i0k
} finally{ l6r%nHP@
try{ [N'r3
if(ps!=null) { d#x8O4S%i2
ps.clearParameters(); .N?|t$J
ps.close(); E&}H\zt#
ps=null; L5hQdT/b$
} {jq^hM!TEy
}catch(SQLException e){} 9aW8wYL~b
DBUtils.closeConnection(conn); R4hav
} BA`kxL/x
} * fOS"-CL
public long getLast(){ }W^V^i )
return lastExecuteTime; g)2m$#T&s
} Fj[ dO&
public void run(){ Lh8#I&x
long now = System.currentTimeMillis(); THegPD67J
if ((now - lastExecuteTime) > executeSep) { p\4h$."
//System.out.print("lastExecuteTime:"+lastExecuteTime); NZC<m$')
//System.out.print(" now:"+now+"\n"); U"jUMOMZ;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); <m|FccvQ
lastExecuteTime=now; roK4RYJ7)
executeUpdate(); MVu[gB
} /3xFd)|Ds
else{ 2gK p\!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); BV_a-\Sa=
} CNpCe-%&
} A5(kOtgiT
} 7`j|tb-
//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 O&gy(
P,s)2 s'nZ
类写好了,下面是在JSP中如下调用。 #t5JUi%in*
>d1aE)?
<% {|t?
CountBean cb=new CountBean(); |\yDgs%EGy
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7z0;FW3>9
CountCache.add(cb); \`p |,j
out.print(CountCache.list.size()+"<br>"); S1 R #]
CountControl c=new CountControl(); ?w|\7T.?
c.run(); URj%
J/jD
out.print(CountCache.list.size()+"<br>"); ?CL z@u~
%>