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: %w}gzxN^
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CountBean.java v/QUjXBr
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/* LJTo\^*
* CountData.java 2YBIWR8z
* X_ TiqV
* Created on 2007年1月1日, 下午4:44 NC"yDWnO'
* rpV1y$n<F
* To change this template, choose Tools | Options and locate the template under ?u$u?j|N
* the Source Creation and Management node. Right-click the template and choose L^J-("e_
* Open. You can then make changes to the template in the Source Editor. 4,P bg|
*/ URTzX
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package com.tot.count; /@oLe[Mz$
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/** b{Zpux+
* pmc=NTr&<
* @author 3=.Y,ENM;
*/ On_@HQ/FI
public class CountBean {
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private String countType; D ]03eu
int countId; 1= VJ&D;
/** Creates a new instance of CountData */ VD7i52xS
public CountBean() {} kdrod [S
public void setCountType(String countTypes){ 1%~ZRmd e
this.countType=countTypes; '+y_\
} wa09$4>_w
public void setCountId(int countIds){ 4B[D/kIg
this.countId=countIds; zc+@lJy
} J%rP$O$
public String getCountType(){ XEH}4;C'{
return countType; +Ic ~ f1zh
} k5BXirB
public int getCountId(){ Snw3`|Y~<
return countId; PGn);Baq
} lU4}B`#"v
} PX
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CountCache.java S;\R!%t_
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/* hsNWqk qys
* CountCache.java J ++v@4Z
* )0 Z! n
* Created on 2007年1月1日, 下午5:01 oF:v
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* X ]j)+DX>
* To change this template, choose Tools | Options and locate the template under A#@_V'a8
* the Source Creation and Management node. Right-click the template and choose Ub$n |xn
* Open. You can then make changes to the template in the Source Editor. ,J=P,](
*/ YV'pVO'_+
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package com.tot.count; p3951-D
import java.util.*; FiAY\4
/** n> w`26MMp
* Sb&lhgW]c
* @author )]6hy9<
*/ ).412I
public class CountCache { !7p}C-RZp
public static LinkedList list=new LinkedList(); 2b@tj
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/** Creates a new instance of CountCache */ z}4L=KR\v
public CountCache() {} ,_v|#g@{
public static void add(CountBean cb){ n.6T
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if(cb!=null){ `FF8ie 8L
list.add(cb); D)b}f`
} ,^s0</ve
} _r Y,}\
} ;@mRo`D`
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CountControl.java k#>hg#G
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/* wFS2P+e;X
* CountThread.java - xm{&0e)
* cD}Sf>
* Created on 2007年1月1日, 下午4:57 W#F Q,+0)
* w`HI]{hE~N
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose [j,txe?n
* Open. You can then make changes to the template in the Source Editor. #&.]"
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*/ -#:zsu
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package com.tot.count; @\P4/+"9
import tot.db.DBUtils; y*b3&%.ml
import java.sql.*; q?j|K|%
/** `{K_/Cit
* oDB`iiBXQ
* @author .i"W8~<e
*/ Qt>>$3]!!
public class CountControl{
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private static long lastExecuteTime=0;//上次更新时间 Bn?V9TEoO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zU5Hb2a
/** Creates a new instance of CountThread */ d=O3YNM:v
public CountControl() {} ;^){|9@
public synchronized void executeUpdate(){ _wDS#t;!M
Connection conn=null; "j<bA8$Vw
PreparedStatement ps=null; ,yMU@Vg
try{ +JyUe
conn = DBUtils.getConnection(); TbVn6V'
conn.setAutoCommit(false); < B g8,;
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); R*pC.QiB~
for(int i=0;i<CountCache.list.size();i++){ QfjN"25_
CountBean cb=(CountBean)CountCache.list.getFirst(); H U+ I
CountCache.list.removeFirst(); E; Y;r"
ps.setInt(1, cb.getCountId()); 62'1X"
ps.executeUpdate();⑴ "UVFU-Z
//ps.addBatch();⑵ zDOKShG
} \6I+K"
//int [] counts = ps.executeBatch();⑶ %b2oiKSBx?
conn.commit(); r{?TaiK
}catch(Exception e){ LaMLv<)k
e.printStackTrace(); _~'+Qe_o$5
} finally{ <PN"oa#
try{ v;1F[?@3Y
if(ps!=null) { n'FwM\
ps.clearParameters(); U/{6%
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ps.close(); Zi\['2CG
ps=null; W;6vpPhg#!
} U977#MXf
}catch(SQLException e){} cu!W4Ub<
DBUtils.closeConnection(conn); )~)*=u/
} G[Lpe
} XMN:]!1J
public long getLast(){ 7 Cqcb>\X
return lastExecuteTime; bru/AZ# de
} (oz$B0HO:
public void run(){ 2.e
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long now = System.currentTimeMillis(); * *H&+T/B
if ((now - lastExecuteTime) > executeSep) { SGc8^%-`
//System.out.print("lastExecuteTime:"+lastExecuteTime); o|pT;1a"
//System.out.print(" now:"+now+"\n"); >JwLk[=j
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;lX(}2tXW
lastExecuteTime=now; E.bi05l
executeUpdate(); bvBHYf:^
} wN-i?Ek0;
else{ 1j-te-}"c
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^D^JzEy'?C
} revF;l6->C
} %^.%OCX:
} YcX/{L[9o
//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 -Y 9SngxM
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类写好了,下面是在JSP中如下调用。 zSvgKmNY
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<% (h-*_a}F4
CountBean cb=new CountBean(); a&{X!:X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); i+3fhV
CountCache.add(cb); vl Ez9/H
out.print(CountCache.list.size()+"<br>"); 2S3lsp5!
CountControl c=new CountControl(); \!50UVzm)
c.run(); EpJ4`{4
out.print(CountCache.list.size()+"<br>"); Z#l%r0(o
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