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: y]E)2:B[d
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CountBean.java 9AVK_
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/* X_0{*!v8
* CountData.java -tK;RQYax
* $ sA~p_]
* Created on 2007年1月1日, 下午4:44 Kd`l[56#
* +e\:C~2f28
* To change this template, choose Tools | Options and locate the template under Q?Bjq>
* the Source Creation and Management node. Right-click the template and choose _Ssv:xc,
* Open. You can then make changes to the template in the Source Editor. DMK"Q#Vw
*/ |04}zU%N
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package com.tot.count; Yn[EI7D
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/** i)`zKbK
* *mK);@pL
* @author *s<dgFA'
*/ Vne.HFXA
public class CountBean { \J3v>&m<7
private String countType; 8,H#t@+MT
int countId; ?4wehcZz
/** Creates a new instance of CountData */ ?Qo_
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public CountBean() {} =AnZ>6
public void setCountType(String countTypes){ c~0VNuN
this.countType=countTypes; eHnei F
} "u,~yxYWl
public void setCountId(int countIds){ 5EV8zf
this.countId=countIds; qs8K jG@
} Be14$7r
public String getCountType(){ L3G)?rPFC#
return countType; (7Ca\H3$
} /k3n{?$/
public int getCountId(){ )qe$rD;N
return countId; G5XnGl}Q
} _!CvtUU0Vv
} g*w-"%"O
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CountCache.java ZZFI\o
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/* cVP49r}}v
* CountCache.java |$|n V^y
*
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* Created on 2007年1月1日, 下午5:01 d~z<,_r5c
* 7z P
* To change this template, choose Tools | Options and locate the template under /xrq'|r?C
* the Source Creation and Management node. Right-click the template and choose g6a3MJV`
* Open. You can then make changes to the template in the Source Editor. c J"]yG)=
*/ d,Dg"Z
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package com.tot.count; ;ijfI
import java.util.*; \ \mO+N47i
/** \'^Z_6{w
* R=Ly49
* @author n
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*/ *V@MAt
public class CountCache { g9lg
public static LinkedList list=new LinkedList(); E*T84Jh6
/** Creates a new instance of CountCache */ T=f;n;/>
public CountCache() {} gx>mKSzy
public static void add(CountBean cb){ 7q{v9xKy
if(cb!=null){ @SQ*/sw (c
list.add(cb); ~cg+BAfu
} W*/s4 N
} n`I
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} KxTYc
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CountControl.java 3_1Io+uXk
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/* C;:1CK
* CountThread.java CyBM4qyH
* 23n8,} H,
* Created on 2007年1月1日, 下午4:57 *
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* Kp=3\) &
* To change this template, choose Tools | Options and locate the template under tL4]6u
* the Source Creation and Management node. Right-click the template and choose vM4`u5
* Open. You can then make changes to the template in the Source Editor. kq.R(z+
*/ v8fZ?dx
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package com.tot.count; ;Q,).@<C
import tot.db.DBUtils; 7rDRu]
import java.sql.*; PA-0FlV|
/** g7Q*KA+
* T[! q&kFB
* @author HOQ
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*/ :~A1Ud4c
public class CountControl{ Y"\T*lKa
private static long lastExecuteTime=0;//上次更新时间 3<'Q`H >
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3L!&~'.Ro
/** Creates a new instance of CountThread */ #]\G*>{
public CountControl() {} yI|?iBc7nC
public synchronized void executeUpdate(){ vheAh`u^&
Connection conn=null; )
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PreparedStatement ps=null; q2U"k
try{ R^O)fL 0_
conn = DBUtils.getConnection(); ?yM/j7Xn
conn.setAutoCommit(false); 2'^OtM,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); N4]6LA6x6
for(int i=0;i<CountCache.list.size();i++){ [t=+$pf(-
CountBean cb=(CountBean)CountCache.list.getFirst(); ;51!aC
CountCache.list.removeFirst(); #&8pp8wd,}
ps.setInt(1, cb.getCountId()); ,HO/Q6;N
ps.executeUpdate();⑴ ToXFMkwY
//ps.addBatch();⑵ {8p?we3l1
} PH4bM
//int [] counts = ps.executeBatch();⑶ Qs[EA_
conn.commit(); C%7)sLWjJS
}catch(Exception e){ X1z0'gvh
e.printStackTrace(); 4y}a,
} finally{ Y&Vbf>Hi+
try{ U
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if(ps!=null) { Pc
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ps.clearParameters(); F1[[fH
ps.close(); VKfHN_m*
ps=null; /ykxVCvAt
} <.B> LU
}catch(SQLException e){} J2k'Ke97o
DBUtils.closeConnection(conn); <W|{)U?p
} kX .1#%Ex
} b6$A@b
public long getLast(){ 9oN'.H^
return lastExecuteTime; m3!MHe~t
} TV>R(D3T/
public void run(){ 8;Bwz RtgT
long now = System.currentTimeMillis(); p~;z"Z
if ((now - lastExecuteTime) > executeSep) { (2\ekct ^
//System.out.print("lastExecuteTime:"+lastExecuteTime); nPX'E`ut-V
//System.out.print(" now:"+now+"\n"); ^p%+r B.j[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zyn =Xv@p
lastExecuteTime=now; B-p5;h>
executeUpdate(); K>JU/(
} kT=|tQ@
else{ ' g!_Flk
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); NP`ll0s
} ?B:wV?-`
} eOO*gM=
} NbMH@6%E
//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 %.gjBI=
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类写好了,下面是在JSP中如下调用。 \bmboNe
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<% 2Sd6b 2-
CountBean cb=new CountBean(); c@{^3V##T
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); aZ3 #g
CountCache.add(cb); 1ucUnNkcV
out.print(CountCache.list.size()+"<br>"); _IGa8=~
CountControl c=new CountControl(); TK?N^ly
c.run(); {$=%5
out.print(CountCache.list.size()+"<br>"); d#,V^
%>