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: %!G]H
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CountBean.java y%21`y&Os
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/* $Xf gY1S
* CountData.java &ESE?{of)
* SG{> t*E
* Created on 2007年1月1日, 下午4:44 ;L5'3+U
* n'yC- ;
* To change this template, choose Tools | Options and locate the template under #l6L7u0~wC
* the Source Creation and Management node. Right-click the template and choose s^]F4'
* Open. You can then make changes to the template in the Source Editor. WvN!8*XFM
*/ ,&;#$ b5
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package com.tot.count; pFLR!/J
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/** 8Q&hhmOnz
* wr/Z)e =^3
* @author G H
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*/ meHAa`
public class CountBean { ]E1aIt
private String countType; 0B^0,d(s
int countId; CF`tNA3fxm
/** Creates a new instance of CountData */ Lzzf`jN]
public CountBean() {} ;hz"`{(JY
public void setCountType(String countTypes){ pv.0!a/M
this.countType=countTypes; =gCv`SFW
} bY4~\cP.
public void setCountId(int countIds){ 3d^zLL
this.countId=countIds; sD,[,6(
} $z!o&3c'x
public String getCountType(){ )p&FDK#ob=
return countType; ;O*y$|+PA
} NJG-~w
public int getCountId(){ A#gmKS<J/7
return countId; 7u"t4Or
} e~C^*w L
} 9Z,vpTE
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CountCache.java OXy>Tlv
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/* 4#$~gTc@
* CountCache.java qm-G=EX
* hKq#i8py
* Created on 2007年1月1日, 下午5:01 NGD?.^ (G
* B{ wx"mK
* To change this template, choose Tools | Options and locate the template under Vd2bG4*=
* the Source Creation and Management node. Right-click the template and choose fZ2>%IxG}
* Open. You can then make changes to the template in the Source Editor. VjbRjn5LI
*/ }ZMbTsm
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package com.tot.count; %t&n%dhJ
import java.util.*; !7MC[z(|N
/** `)`J
* d`D<PT(\
* @author )GDP?Nc<Ik
*/ =,q,W$-
public class CountCache { :yN;_bC!b%
public static LinkedList list=new LinkedList(); qEC-'sl<
/** Creates a new instance of CountCache */ ^u zJu(
public CountCache() {} 4^T@n$2N
public static void add(CountBean cb){ Xqt3p6
if(cb!=null){ uXiAN#1
list.add(cb); <StyO[
} acgtXfHR
} Y27x;U
} -/:N&6eRb
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CountControl.java C%LRb{|d
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/* D[2I_3[wp
* CountThread.java 3fJGJW!zu
* f>k<I[C<
* Created on 2007年1月1日, 下午4:57 ]iewukB4
* 0z@KkU{Z
* To change this template, choose Tools | Options and locate the template under a%"mgCB
* the Source Creation and Management node. Right-click the template and choose '!*,JG5_
* Open. You can then make changes to the template in the Source Editor. +H5=zf2
*/ gWm
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package com.tot.count; V @A+d[
import tot.db.DBUtils; \2(Uqf#_
import java.sql.*; (9r\YNK
/** "oZ-W?IK E
* l+BJh1^
* @author R}MdBE
*/ 7e\g
public class CountControl{ z1t
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private static long lastExecuteTime=0;//上次更新时间 Tbl~6P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 GAONgz|ZI
/** Creates a new instance of CountThread */ FA-""]
public CountControl() {} "'us.t.
public synchronized void executeUpdate(){ CV% AqJN
Connection conn=null; 1|)l6#hOL
PreparedStatement ps=null; ig(a28%
try{ B#RwW,
conn = DBUtils.getConnection(); j(4BMk
conn.setAutoCommit(false); <aJdm!6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); T4,dhS|
for(int i=0;i<CountCache.list.size();i++){ n?vw|'(}
CountBean cb=(CountBean)CountCache.list.getFirst(); }eUeADbC
CountCache.list.removeFirst(); \}SA{)
ps.setInt(1, cb.getCountId()); /t=R~BJu
ps.executeUpdate();⑴ BdcTKC
//ps.addBatch();⑵ ]-d:wEj
} UR|UGldt_T
//int [] counts = ps.executeBatch();⑶ HvSKR1wL\
conn.commit(); M{gtu'.
}catch(Exception e){ 8Fy$'Zx'
e.printStackTrace(); 8&g|iG
} finally{ 9%e&Z'l
try{ >S4klW=*I
if(ps!=null) { %Q:i6 ~
ps.clearParameters(); LaL.C^K
ps.close(); o7"2"(
=>
ps=null; [MfKBlA
} ?bwF$Ku
}catch(SQLException e){} ?4%'6R
DBUtils.closeConnection(conn); t_HS0rxG
} ea-NqdGs;m
} .v<c_~y
public long getLast(){ asT:/z0
return lastExecuteTime; _"
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} VT1Nd
public void run(){ J(+I`
long now = System.currentTimeMillis(); <fq?{z
if ((now - lastExecuteTime) > executeSep) { MW|Qop[
//System.out.print("lastExecuteTime:"+lastExecuteTime); E)liuu!qI
//System.out.print(" now:"+now+"\n"); OYKeu(=L
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); OZ\ ]6]L
lastExecuteTime=now; |_V i8Ly
executeUpdate(); zlC|Sp af
} AfmGA9
else{ pC 5J
'@
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }HB)%C50.
} C%8nr8po
} >5C|i-HX
} EsR_J/:Qe
//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 U 2k^X=yl
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类写好了,下面是在JSP中如下调用。 ?3bUE\p
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<% sM)qzO2wh
CountBean cb=new CountBean(); >SO !{
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); C' x?riJ/
CountCache.add(cb); q{/>hvl
out.print(CountCache.list.size()+"<br>"); v'Y)~Kv@!
CountControl c=new CountControl(); pE{ZWW[@+
c.run(); n_5m+
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out.print(CountCache.list.size()+"<br>"); L'k)
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