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: \7yJ\I
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CountBean.java Wm(:P
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/* n'yl)HA~>`
* CountData.java 8)pB_en3sO
* L?HF'5o
* Created on 2007年1月1日, 下午4:44 ~
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* ilv _D~|
* To change this template, choose Tools | Options and locate the template under >Fyu@u
* the Source Creation and Management node. Right-click the template and choose
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* Open. You can then make changes to the template in the Source Editor. '*4iqPR;
*/ ,ijW(95{k
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package com.tot.count; JA<~xo[Q9
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/**
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* AFGwT%ZD
* @author KSc~GP_
*/ =5ug\S
public class CountBean { @ u+|=x];
private String countType; ZOu R"9]
int countId; )!eEO [\d
/** Creates a new instance of CountData */ &Pq\cNYzW
public CountBean() {} Lyr2(^#:
public void setCountType(String countTypes){ G?<pBMy
this.countType=countTypes; LJWTSf"f?
} B7!;]'&d
public void setCountId(int countIds){ frc{>u~t
this.countId=countIds; uf]Y^,2
} E5gl ^Q?Z
public String getCountType(){ ,E?4f
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return countType; "Hht
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} 4[1k\
public int getCountId(){ y@3kU*-1
return countId; c;wA
} )Oiev u_"|
} b+Vi3V
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CountCache.java A*F9\mjI5
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/* Sph*1c(R
* CountCache.java hM>*a!)U
* = /Wu'gG)
* Created on 2007年1月1日, 下午5:01 @+&'%1
* kwlC[G$j7
* To change this template, choose Tools | Options and locate the template under #V[SQ=>x[
* the Source Creation and Management node. Right-click the template and choose 4fty~0i=z
* Open. You can then make changes to the template in the Source Editor. g/#~N~&
*/ YBvd
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package com.tot.count; E0YU[([G
import java.util.*; eu9w|g
/** @6b[GekZ<
* Q>=-ext}q
* @author *H"aOT^{
*/ fK_~lGY(
public class CountCache { ;Iq5|rzDn
public static LinkedList list=new LinkedList(); 6m+W#]^
/** Creates a new instance of CountCache */ [))JX"a
public CountCache() {} hk}
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public static void add(CountBean cb){ Pq?*C;D
if(cb!=null){ v9rVpYc"
list.add(cb); Q#pnj thM
} h<% U["
} ~<,Sh~Ana.
} H&bh<KPMh
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CountControl.java 6m[9b*s7
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/* a#y{pT2 b
* CountThread.java dB3N%pB^
* %S`ik!K"I
* Created on 2007年1月1日, 下午4:57 7Z0/(V.-
* }g{_AiP
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* To change this template, choose Tools | Options and locate the template under 2ykCtRe
* the Source Creation and Management node. Right-click the template and choose b_vTGl1_6
* Open. You can then make changes to the template in the Source Editor. 3dG4pl~
*/ %[Zz0|A
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package com.tot.count; ]"sRS`0+
import tot.db.DBUtils; x=Mm6}/
import java.sql.*; Wc|z7P~',%
/** ^|?1_r
* ?3jdg ]&
* @author rzu
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*/ G),db%,X2
public class CountControl{ Yy
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private static long lastExecuteTime=0;//上次更新时间 [Oy >R
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4RQ5(YTTuR
/** Creates a new instance of CountThread */ Y<Q\d[3^F
public CountControl() {} qq;b~ 3kW
public synchronized void executeUpdate(){ zvr\36
Connection conn=null; yX!#a>d"H
PreparedStatement ps=null; (Es{l a G
try{ Rla4L`X;
conn = DBUtils.getConnection(); kcS6 _l
conn.setAutoCommit(false); 3LW[H+k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *jF#^=
for(int i=0;i<CountCache.list.size();i++){ U$'y_}V
CountBean cb=(CountBean)CountCache.list.getFirst(); C[YnrI!
CountCache.list.removeFirst(); +'XhC#:
ps.setInt(1, cb.getCountId()); l^r' $;<m
ps.executeUpdate();⑴ Mr*|9h
//ps.addBatch();⑵ S$O,] @)
} 2EfflZL3
//int [] counts = ps.executeBatch();⑶ "HC)/)Mv@
conn.commit(); c7qwNs*f
}catch(Exception e){ [H,u)8)
e.printStackTrace(); !8$RBD %
} finally{ }q'WC4.
try{ GuO`jz F
if(ps!=null) { doD>m?rig3
ps.clearParameters(); ><Uk*mwL
ps.close(); T"!EK&
ps=null; /s[DI;M$o
} ``9 GY
}catch(SQLException e){} o.^y1mH'
DBUtils.closeConnection(conn); ` X}85
} / Z!i;@Wf
} D$nK`r
public long getLast(){ K"l0w**Og#
return lastExecuteTime; @\}YAa>>"I
} 3hS6jS
public void run(){ l h/&__
long now = System.currentTimeMillis(); M<[?g5=#
if ((now - lastExecuteTime) > executeSep) { irMd
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//System.out.print("lastExecuteTime:"+lastExecuteTime); %MJ;Q?KB
//System.out.print(" now:"+now+"\n"); 8#59iQl
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); mP-2s;q
lastExecuteTime=now; Y {c5
executeUpdate(); !Iq{ 5:
} &1GUi{I
else{ bGv4.:)
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p4>,Fwy2
} CLN+I'uX0
} %S#WPD'Y
} `|<+ ?
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 (~()RkT
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类写好了,下面是在JSP中如下调用。 m mw-a0
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<% Q6^x8
CountBean cb=new CountBean(); 6fwY$K\X
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >n!ni(
CountCache.add(cb); ~HDdO3
out.print(CountCache.list.size()+"<br>"); Np)aS[9W
CountControl c=new CountControl(); dWR1cvB(wY
c.run(); _/ Os^ >R
out.print(CountCache.list.size()+"<br>"); >.LKct*5K
%>