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: UnjUA!v
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CountBean.java n1Ag o3NM
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/* 8YI.f
* CountData.java qwka77nNT
* a^+b(&;k
* Created on 2007年1月1日, 下午4:44 .MO"8}]8Z
*
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* To change this template, choose Tools | Options and locate the template under n*\AB=|X
* the Source Creation and Management node. Right-click the template and choose wzAp`Zs2Dm
* Open. You can then make changes to the template in the Source Editor. r>lC(x\B
*/ H
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package com.tot.count; A{hwT,zV:
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/** 9.5hQZ
* 6ju+#]T
* @author l'N>9~f
*/ ?9q{b\=l
public class CountBean { IXp P.d
private String countType; |N[SCk>Kj
int countId; r ]1|I6:&)
/** Creates a new instance of CountData */ [.P~-6~
public CountBean() {} d>F=|dakL
public void setCountType(String countTypes){ >u5}5OP7
this.countType=countTypes; .ao'o,|vE
} %j=E}J<H5*
public void setCountId(int countIds){ ih1s`CjG
this.countId=countIds; k}-%NkQ
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} 9;;1 "^4/
public String getCountType(){ M3 8,SH<
return countType; %V;k/w~[
} w&;\}IS
public int getCountId(){ }/G~"&N[
return countId; r2QC$V:0
} zqYfgV
} e*vSGT$KgL
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CountCache.java 'dj}- Rs
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/* ;BoeE3*
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* CountCache.java /S9Mu
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* `(.ue8T
* Created on 2007年1月1日, 下午5:01 @N.W#<IG
* c[ff|-<g
* To change this template, choose Tools | Options and locate the template under =]7|*-
* the Source Creation and Management node. Right-click the template and choose )+w0NhJw
* Open. You can then make changes to the template in the Source Editor. cJ:BEe
*/ 4$.UVW\
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package com.tot.count; [.z1
import java.util.*; 0e8)*2S
/** ZH:#~Zyj
* IG +nrTY0
* @author OAw/
*/
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public class CountCache { GLc+`,.
public static LinkedList list=new LinkedList(); C& Nd|c
/** Creates a new instance of CountCache */ 1t!Mg{&e[x
public CountCache() {} 2T?t[;-
public static void add(CountBean cb){ u[ 2R>=
if(cb!=null){ k1-?2kf"{
list.add(cb); RWA|%/L
} X+iA"B
} M~N'z/
} =]W{u`
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CountControl.java 0e vxRcrzz
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/* 7SAu">lIl
* CountThread.java (a7IxW
* ^r;}6
* Created on 2007年1月1日, 下午4:57 [+GQ3Z\
* S2jo@bp!
* To change this template, choose Tools | Options and locate the template under by6E
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* the Source Creation and Management node. Right-click the template and choose <;9vwSH>
* Open. You can then make changes to the template in the Source Editor. @gX@mT"
*/ F>*w)6 4~
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package com.tot.count; ]]%C\Ryy}
import tot.db.DBUtils; W97Ka}Y
import java.sql.*; nsgNIE{>gO
/** Vp5qul%
* I8^z\ef&
* @author YVW!u6W'[6
*/ T/S-}|fhQ
public class CountControl{ ,u]kZ ]
private static long lastExecuteTime=0;//上次更新时间 fvNGGn!
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 m@HU;J\I
/** Creates a new instance of CountThread */ yMz@-B
public CountControl() {} }3[ [ONA
public synchronized void executeUpdate(){ G2L7_?/m
Connection conn=null; a.8 nWs^
PreparedStatement ps=null; $ HUCp9
try{ yxA0#6so
conn = DBUtils.getConnection(); l^0
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conn.setAutoCommit(false); 4dfe5\
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ?# G_&
for(int i=0;i<CountCache.list.size();i++){ dwx1EdJ{
CountBean cb=(CountBean)CountCache.list.getFirst(); R!$j_H
CountCache.list.removeFirst(); NpRC3^
ps.setInt(1, cb.getCountId()); L7Skn-*tnA
ps.executeUpdate();⑴ mbS
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//ps.addBatch();⑵ UhEJznfi
} &x=<>~Ag3
//int [] counts = ps.executeBatch();⑶ ,hOJe=u46
conn.commit(); 7?hCt
}catch(Exception e){ ?on3z
e.printStackTrace(); b$gDFNa
} finally{
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try{ j@9nX4Z
if(ps!=null) { oN _%oc
ps.clearParameters(); NWNgh/9?
ps.close(); 6 'wP?=
ps=null; $V\xN(Ed
} , H[o.r=
}catch(SQLException e){} z1]RwbA?1
DBUtils.closeConnection(conn); DDkOg]
} hUlFP
} TS1k'<c?
public long getLast(){ _wHqfj)
return lastExecuteTime; 9CL&tpqv
f
} E|^a7-}|
public void run(){ e94csTh=
long now = System.currentTimeMillis(); D@j `'&G
if ((now - lastExecuteTime) > executeSep) { {=R=\Y?r&
//System.out.print("lastExecuteTime:"+lastExecuteTime); s}HTxY;
//System.out.print(" now:"+now+"\n"); +5T0]!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); myJsRb5
lastExecuteTime=now; ="I]D
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executeUpdate(); 8\ :T*u3
} I.(
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else{ x&?35B
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); khEHMvVH
} H ($=k-+5
} Z&}94
} cPtP?)38.
//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 P|64wq{B8
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类写好了,下面是在JSP中如下调用。 2#py>rF(
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<% _e?(Gs0BM
CountBean cb=new CountBean(); ;>YJ}:r"\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 2j_L
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CountCache.add(cb); 5qFqH
out.print(CountCache.list.size()+"<br>"); 9RAN$\AKy
CountControl c=new CountControl(); Z/2#h<zj
c.run(); wRWN]Vo
out.print(CountCache.list.size()+"<br>"); W}T$ Z
%>