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: "K/[[wX\b
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CountBean.java 3}v0{c
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/* A&xab
* CountData.java tj`tLYOZ@-
* ]:[)KZ~
* Created on 2007年1月1日, 下午4:44 ))8Emk^Q{
* )zo#1$C-
* To change this template, choose Tools | Options and locate the template under = E##},N"
* the Source Creation and Management node. Right-click the template and choose L.R"~3
* Open. You can then make changes to the template in the Source Editor. IS3e|o*]MP
*/ "TEBByO'
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package com.tot.count; $K5ni {M;
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/** i7Y
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* BXagSenc
* @author gK&5HTo
*/ %g2/o^c*
public class CountBean { GGYX!=]~
private String countType; oHv{Y
int countId; @2-Hj~
/** Creates a new instance of CountData */ s|fCR
public CountBean() {} 1jR=h7^=
public void setCountType(String countTypes){ S.zg&
this.countType=countTypes; ,<R>Hiwg/s
} WRN8#b
public void setCountId(int countIds){ hpd(d$j
this.countId=countIds; Fr938q6^-
} Uqb]e?@
public String getCountType(){ g6x/f<2x
return countType; S,ouj;B
} F(?Fz8
public int getCountId(){ (CKhY~,/u
return countId; Vu_7uSp,)
} (,d4"C
} v9X7-GJ~
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CountCache.java u K+9gTv
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/* }z9I`6[
* CountCache.java a>;3
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* +xoyKP!
* Created on 2007年1月1日, 下午5:01 9b"}CEw
* 60Xl.
* To change this template, choose Tools | Options and locate the template under [qO5~E`;
* the Source Creation and Management node. Right-click the template and choose 2ID*U d*
* Open. You can then make changes to the template in the Source Editor. y@2vY[)3s
*/ #U\&i`
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package com.tot.count; YD0vfwh
import java.util.*; yBXkN&1=%;
/** =|j*VF 2y"
* (6b?ir ~
* @author !3b|*].B
*/ I{*.htt{
public class CountCache { tkm~KLWV&7
public static LinkedList list=new LinkedList(); |IyM"UH
/** Creates a new instance of CountCache */ rw40<SS"Z
public CountCache() {} v%69]a-T
public static void add(CountBean cb){ e{qp!N1!
if(cb!=null){ , u8ZS|9
list.add(cb); {Oc?C:aI=
} t(uB66(_F
} ~#IWM+I
} "G i+zkVm
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CountControl.java X-*KQ+?
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/* .&*
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* CountThread.java =DmPPl{
* vkNZ -`+I
* Created on 2007年1月1日, 下午4:57 IxK 3,@d
* n;S0fg
* To change this template, choose Tools | Options and locate the template under eY6gb!5u
* the Source Creation and Management node. Right-click the template and choose 7>W+Uq
* Open. You can then make changes to the template in the Source Editor. 9}'l=b:Jms
*/ O|^6UH
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package com.tot.count; >h/)r6
import tot.db.DBUtils; _^ CQ*+F
import java.sql.*; <.?^LT
/** z Et6
* :3E8`q~c1
* @author ;ZE<6;#3IP
*/ ^G7n#
public class CountControl{ RpaA)R,
private static long lastExecuteTime=0;//上次更新时间 $@ T6g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qw
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/** Creates a new instance of CountThread */ gOES2
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public CountControl() {} ATXx?
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public synchronized void executeUpdate(){ ?=|)n%
Connection conn=null; 2S7H_qo$
PreparedStatement ps=null; m\}\RnZu
try{ =oKPMmpCZ
conn = DBUtils.getConnection(); Bcd0
conn.setAutoCommit(false); Hm8EYPrJ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;k63RNT,M&
for(int i=0;i<CountCache.list.size();i++){ ]
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CountBean cb=(CountBean)CountCache.list.getFirst(); pO 7{3%
CountCache.list.removeFirst(); 4/mj"PBKL
ps.setInt(1, cb.getCountId()); vt(}ga
ps.executeUpdate();⑴ F_M~!]<na
//ps.addBatch();⑵ Xx9~
} ~YT>:Np
//int [] counts = ps.executeBatch();⑶ (`uC"M Lk
conn.commit(); u}@%70A
}catch(Exception e){ c-3Y SrY
e.printStackTrace(); )n3biQL_
} finally{ 4%c7#AX[T
try{ 2!~>)N
if(ps!=null) { Y+PvL|`O
ps.clearParameters(); _+R_ms
ps.close(); ek0;8Ds9
ps=null; x/jN&;"/
} Do[ F+Y
}catch(SQLException e){} zvQ^f@lq2
DBUtils.closeConnection(conn); Sj]T{3mi
} D .oS8'
} MR l*rK
public long getLast(){ /S=;DxZ,r
return lastExecuteTime; 2}xFv2X
} |Z^c#R
public void run(){ )lngef
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long now = System.currentTimeMillis(); E#HU?<q8
if ((now - lastExecuteTime) > executeSep) { _>:=<xyOq
//System.out.print("lastExecuteTime:"+lastExecuteTime); T$8$9D_u
//System.out.print(" now:"+now+"\n"); :BZx)HxQ
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); oRJP5Y5na
lastExecuteTime=now; #9W5
executeUpdate(); W<Vzd4hR
} w]+BBGYQKb
else{ oE|{|27X
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); hz~CW-47
} 5+Zx-oWq_
} EuimZW\V
} 1o"oa<*_
//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 *IO;`k q,;
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类写好了,下面是在JSP中如下调用。 Wp9
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<% 3vGaT4TDx
CountBean cb=new CountBean(); U*+!w@
.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |@bNd7=2d
CountCache.add(cb); Z@aL"@2]a
out.print(CountCache.list.size()+"<br>"); wGQ hr="
CountControl c=new CountControl(); %H 6ZfEO
c.run(); !+26a*P
out.print(CountCache.list.size()+"<br>"); hK9oe%kU~
%>