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: 41XS/# M$*
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CountBean.java ui .riD[,O
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/* A1p87o>
* CountData.java ]Dd}^khv
* ur@"wcl"V
* Created on 2007年1月1日, 下午4:44 U'oFW@Y;h
* Ucqn3&
* To change this template, choose Tools | Options and locate the template under dVKctt'C
* the Source Creation and Management node. Right-click the template and choose tE(_Cg
* Open. You can then make changes to the template in the Source Editor. : pkOZ+t
*/
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package com.tot.count; *P;
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/** [~Vj(H=KwI
* [yn\O=%5
* @author \NF5)]:
*/ ?K!^[aO}=
public class CountBean { /t|Lu@&:Xo
private String countType; HOSt0IHzty
int countId; c_ Dg0
/** Creates a new instance of CountData */ bD:[r))#e
public CountBean() {} 4^3lG1^YY
public void setCountType(String countTypes){ \3XG8J
this.countType=countTypes; )C&'5z
} uN*Ynf(:-
public void setCountId(int countIds){ ;_iDiLC;
this.countId=countIds; ;k fl5
} j0uu*)Rk
public String getCountType(){ u5O`|I@R
return countType; );!IGcgF
} <.knM
public int getCountId(){ A V]7l}-
return countId; ; nc3O{rU
} LM2S%._cj;
} `P
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CountCache.java X6-;vnlKN
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/* bB+ 4
* CountCache.java 1a]QNl_x
* UNF@%O4_T
* Created on 2007年1月1日, 下午5:01 DcRvZH
* E5QQI9ea
* To change this template, choose Tools | Options and locate the template under ZGsI\3S
* the Source Creation and Management node. Right-click the template and choose y"T(Unvc
* Open. You can then make changes to the template in the Source Editor. &\m=|S
*/ ,p)Qu%'
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package com.tot.count; ?8-ho0f0
import java.util.*; ep)O|_=
/** H~<w*[uT
* Yow
* @author yB5JvD ?
*/ 4'#?"I
public class CountCache { OVUJiBp
public static LinkedList list=new LinkedList(); vJ9IDc|[
/** Creates a new instance of CountCache */ /I48jO^2
public CountCache() {} =Y
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public static void add(CountBean cb){ qtlcY8!
if(cb!=null){ sIzy/W0iV
list.add(cb); M{4U%lk
} b<27XZ@
} a&!K5(
} m"f3hd4D_q
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CountControl.java tRVz4fk[G
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/*
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* CountThread.java 1"S~#
* P^^WViVX
* Created on 2007年1月1日, 下午4:57 {wh, "Ok_
* |crm{]7X
* To change this template, choose Tools | Options and locate the template under L/xTW
* the Source Creation and Management node. Right-click the template and choose NiBly
* Open. You can then make changes to the template in the Source Editor. 0q o]nw
*/ ;iO5
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package com.tot.count; JXQh$hs
import tot.db.DBUtils; HlOn=>)<
import java.sql.*; +!cibTQTT
/** 1b,MJ~g$
* 2#Du5d
* @author NCivh&HR
*/ dZ|x `bIgs
public class CountControl{ V.}3d,Em%]
private static long lastExecuteTime=0;//上次更新时间 YB]{gm2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 S+bpWA
/** Creates a new instance of CountThread */ c&'5r OY~
public CountControl() {} [w{x+6uX'
public synchronized void executeUpdate(){ |ngv{g
Connection conn=null; {F ',e~}s
PreparedStatement ps=null; #CRd@k?
try{ ymb{rKkN3
conn = DBUtils.getConnection(); m[qW)N:w
conn.setAutoCommit(false); _)ZxD--Qg
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;T :]?5W!
for(int i=0;i<CountCache.list.size();i++){ VQ8Q=!]
CountBean cb=(CountBean)CountCache.list.getFirst(); 4 u=v
CountCache.list.removeFirst(); 2= zw!
ps.setInt(1, cb.getCountId()); R1~wzy
ps.executeUpdate();⑴ ,}/6Za
//ps.addBatch();⑵ Gz:ell$
} W!V-m
//int [] counts = ps.executeBatch();⑶ ]([^(&2
conn.commit(); IG90mpLX
}catch(Exception e){ 9`td_qh
e.printStackTrace(); )Wy:I_F351
} finally{ ~EM(*k._
try{ rUg|5EN^)d
if(ps!=null) { 'x<o{Hi"\B
ps.clearParameters(); (W
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ps.close(); .'bhRQY
ps=null; J1Run0
} @_0tq {
}catch(SQLException e){} H;MyT Vl
DBUtils.closeConnection(conn); +!mEP>
} -5Oy k,
} Ff1!+P,
public long getLast(){ 8'M:uI
return lastExecuteTime; {a0yHy$H
} IXpn(vX
public void run(){ Zp/$:ny
long now = System.currentTimeMillis(); r3dGXiu
if ((now - lastExecuteTime) > executeSep) { ) uTFId
//System.out.print("lastExecuteTime:"+lastExecuteTime); O=}d:yZb!
//System.out.print(" now:"+now+"\n"); hA1p#
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); L&0aS:
lastExecuteTime=now; YySo%\d
executeUpdate(); S]Ye`
} 6&o?#l;|
else{ *p0Kw>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); uyvjo)T
} o(yyj'=(
} Id=V\'$o
} %D3Asw/5a
//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 Nx"|10gC
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类写好了,下面是在JSP中如下调用。 Of>2 m<
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<% $f=6>Kn|^]
CountBean cb=new CountBean(); W'6sY@0m
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); F+!9T
CountCache.add(cb); aU*}.{<!
out.print(CountCache.list.size()+"<br>"); \_x~lRqJJ
CountControl c=new CountControl(); Vwb_$Yi+]
c.run();
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out.print(CountCache.list.size()+"<br>"); CU:HTz=
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