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: $Xt""mlQ
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CountBean.java ;5X~"#%U_
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/* \jk*Nm8;
* CountData.java l2n`fZL
* NbU4|Oi
* Created on 2007年1月1日, 下午4:44 t^MTR6y+8
* AcnY6:3Y|
* To change this template, choose Tools | Options and locate the template under }G{"Mp4
* the Source Creation and Management node. Right-click the template and choose Rq+7&%dy
* Open. You can then make changes to the template in the Source Editor. _GxC|d
*/ w=_^n]`R
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package com.tot.count; `+< ^Svou
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/** HN`qMGW^
* Co nik`
* @author ?m~1b_@A{
*/ RICm$,
public class CountBean { jRiMWolLv
private String countType; Q]=/e7
int countId; \='LR!_
/** Creates a new instance of CountData */ N,XjZ26
public CountBean() {} t{},Th
public void setCountType(String countTypes){ M}X `
this.countType=countTypes; OHAU@*[lM
} ,rN$ah$CL
public void setCountId(int countIds){ _Cz98VqRk
this.countId=countIds; hfIP
} D`G; C
public String getCountType(){ `~d7l@6F
return countType; RYvdfj.ij
} A/a=)su
public int getCountId(){ CB>W# P%
return countId; BJ3<"D{.*4
} |$IL:W6
} f@!9~s
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CountCache.java Z}0{FwW"4
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/* yI|x
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* CountCache.java F;`c0ja]
* ]XlBV-@b
* Created on 2007年1月1日, 下午5:01 "9[2vdSX
* ;&|I/MVm
* To change this template, choose Tools | Options and locate the template under ]SAY\;,_
* the Source Creation and Management node. Right-click the template and choose 1mtYap4
* Open. You can then make changes to the template in the Source Editor. ^bPpcm=
*/ 2jhJXM=~
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package com.tot.count; +UOVD:G
import java.util.*; 5!'1;GLs
/** :D3:`P>,c
* k*2khh-
* @author /8]K}yvR
*/ <L8FI78[*
public class CountCache { i75\<X
public static LinkedList list=new LinkedList(); e%ro7~
/** Creates a new instance of CountCache */ 7wW x 8
public CountCache() {} PhuHfw4$y,
public static void add(CountBean cb){ LFi{Q{E)
if(cb!=null){ j|[$P4w}U
list.add(cb); F|+B8&-v
} a.UYBRP/l
} Pm^FSw"
} o8:9Yjs
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CountControl.java <tZtt9j_
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/* 56kqG}mg&
* CountThread.java 'W9[Vm
* _\IA[-C+O
* Created on 2007年1月1日, 下午4:57 sd+_NtH
* %e25Z.Se$
* To change this template, choose Tools | Options and locate the template under Or$"f3gq
* the Source Creation and Management node. Right-click the template and choose ?1r;6
* Open. You can then make changes to the template in the Source Editor. T}?b,hNl$
*/ T[e+iv<8j
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package com.tot.count; v~AshmP
import tot.db.DBUtils; ;,]4A{|
import java.sql.*; /#{~aCOi)
/** O251. hXK
* Sru0j/|H\
* @author *^{j!U37s
*/ d,i4WKp
public class CountControl{ C%<Dq0j
private static long lastExecuteTime=0;//上次更新时间 OB=bRLd.IR
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 pheu48/f
/** Creates a new instance of CountThread */ @mu{*. &
public CountControl() {} %/\sn<6C}
public synchronized void executeUpdate(){ G2n.NW#d4
Connection conn=null; dzbbFvG
PreparedStatement ps=null; ;m|N9'
try{ kc$W"J@
conn = DBUtils.getConnection(); lBG=jOS
conn.setAutoCommit(false); E*T6kp^b
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 9-{.W Z
for(int i=0;i<CountCache.list.size();i++){ |*ZM{$
CountBean cb=(CountBean)CountCache.list.getFirst(); .#tA .%
CountCache.list.removeFirst(); `%Kj+^|DS
ps.setInt(1, cb.getCountId()); 5G2ueRVb
ps.executeUpdate();⑴ qh}+b^Wi
//ps.addBatch();⑵ Z;+;_Cw
} "UY34a^I
//int [] counts = ps.executeBatch();⑶ 3zfpFgD!
conn.commit(); Lfa&JKd
}catch(Exception e){ )D+eWo
e.printStackTrace(); )xg8#M=K
} finally{ Sa)L=5Nr
try{ Z{%W!>0
if(ps!=null) { Y@UW\d*'%I
ps.clearParameters(); &09~ D8f'
ps.close(); O:,Gmft+
ps=null; 46l*ui_
} *b{Hj'H aH
}catch(SQLException e){} 01
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DBUtils.closeConnection(conn); 8(NS;?
} =kq<J-:#R
} beYGP
public long getLast(){ ,=@WE>ip
return lastExecuteTime; d8
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} V$$9Rh
public void run(){ 1=>b\"P#E
long now = System.currentTimeMillis(); k'F*uS
if ((now - lastExecuteTime) > executeSep) { DN*M-o9
//System.out.print("lastExecuteTime:"+lastExecuteTime); iV@\v0k
//System.out.print(" now:"+now+"\n"); 9.~_swkv
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]CU)#X<J
lastExecuteTime=now; [zP}G?(
executeUpdate(); Pu!C,7vUQ
} "tmu23xQ
else{ 1p/_U?H:|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `\ nKPj
} &432/=QSm0
} J7EWaXGbz
} .VmRk9Z
//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 J1M9),
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类写好了,下面是在JSP中如下调用。 9w0v?%%_
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<% ]-heG'y]{
CountBean cb=new CountBean(); (yT&&_zY4
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9zBt
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CountCache.add(cb); g[ @Q iy
out.print(CountCache.list.size()+"<br>"); }HbUB$5
CountControl c=new CountControl(); `5x0p a
c.run(); Xk/:a}-l
out.print(CountCache.list.size()+"<br>"); +-V4:@
%>