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: Jlzhn#5c-
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CountBean.java 6S<pWR~
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/* @M(vaJB8u
* CountData.java ,
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* shi#K<gVC
* Created on 2007年1月1日, 下午4:44 ?e BN_a,r6
* 55#H A?cR
* To change this template, choose Tools | Options and locate the template under uto4bs:
* the Source Creation and Management node. Right-click the template and choose Kp"o0fh<9
* Open. You can then make changes to the template in the Source Editor. \Wo,^qR
*/ hWUZn``U$|
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package com.tot.count; SDot0`s>
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/** rod{77
* ?(mlt"tPk
* @author -O ej6sILO
*/ ?&Lb6(}e
public class CountBean { /JvNJ
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private String countType; kY*D s;
int countId; C9~CP8
/** Creates a new instance of CountData */ LTi0,03l<
public CountBean() {} LOp<c<+aW
public void setCountType(String countTypes){ $FD0MrB_+
this.countType=countTypes; N[AX29
} !#>{..}}3
public void setCountId(int countIds){ _xbVAI4
this.countId=countIds; 3D\I#g
} lc*<UZR
public String getCountType(){ aK,G6y
return countType; P2lj#aQLS
} :imp~~L;
public int getCountId(){ wp} PQw:
return countId; rHP5;j<]
} -{ZRk[>Z
} <Q%\pAP}b
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CountCache.java lwa
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/* :V8 \^
* CountCache.java Ix}:!L
* Jz3u r)|
* Created on 2007年1月1日, 下午5:01 ab6KK$s
* r=u>TA$
* To change this template, choose Tools | Options and locate the template under OJ&~uV >2
* the Source Creation and Management node. Right-click the template and choose ]mYY1%H8M
* Open. You can then make changes to the template in the Source Editor. 'H97D-86/
*/ n&&X{Rl
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package com.tot.count; G!wFG-Y}
import java.util.*; X+iUT
/** kvKbl;<
* z`'{l{
* @author @'dtlY5;
*/ I>:M1Yc0
public class CountCache { *;Sj&O
public static LinkedList list=new LinkedList(); b1_HDC(
/** Creates a new instance of CountCache */ *_@8 v?
public CountCache() {} _},u[+
public static void add(CountBean cb){ .h{`e>d
if(cb!=null){ B!6?+<J"
list.add(cb); yy G:Kl
} G9d@vu
} .%.J Q
} >/GVlXA'
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CountControl.java iku) otUc
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/* {4\(HrGNk
* CountThread.java .t$~>e
.
* NZCPmst
* Created on 2007年1月1日, 下午4:57 bfhap(F~(e
* ~:v" TuuK
* To change this template, choose Tools | Options and locate the template under n YWS'i@
* the Source Creation and Management node. Right-click the template and choose ]|'Mf;
* Open. You can then make changes to the template in the Source Editor. r+ k5Bk'
*/ oF8#gn_
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package com.tot.count; %,1bh
import tot.db.DBUtils; =UT*1-yhR
import java.sql.*; d%8hWlffz
/** 0escp~\Z
* )BmK'H+l
* @author +<7`Gn(n3
*/ |]*]k`o<)
public class CountControl{ v?vm-e
private static long lastExecuteTime=0;//上次更新时间 DavpjwSn
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 :[A>O(
/** Creates a new instance of CountThread */ )w=ehjV^m
public CountControl() {} *\L\Bzm
public synchronized void executeUpdate(){ ncjtv"2R
Connection conn=null; z^'3f!:3
PreparedStatement ps=null; :*k
try{ V]&0"HX2r!
conn = DBUtils.getConnection(); ]Vuq)#
conn.setAutoCommit(false); K`Vi5hR~c
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); x(ue
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for(int i=0;i<CountCache.list.size();i++){ /J9|.];%r
CountBean cb=(CountBean)CountCache.list.getFirst(); unY+/p $
CountCache.list.removeFirst(); /-4rcC
ps.setInt(1, cb.getCountId()); W!MO}0s
ps.executeUpdate();⑴ %L, mj
//ps.addBatch();⑵ L/t'|<m
} iK%%
//int [] counts = ps.executeBatch();⑶ lpi^<LQ@l
conn.commit(); jv_z%`
}catch(Exception e){ Rf9;jwU
e.printStackTrace(); m:_'r"o
} finally{ K*NCIIDh
try{ _[SW8 9zk
if(ps!=null) { W"MwpV
ps.clearParameters(); {$5?[KD
ps.close(); AR8zCKBc^
ps=null; cdY|z]B
} >PHin%#
}catch(SQLException e){} z3>ldT
DBUtils.closeConnection(conn); 7|bzopLJk
} "&lQ5]N.%
} H!PMb{e
public long getLast(){ ]jQj/`v1
return lastExecuteTime; wA$ JDf)Vg
} jJc:%h$|2
public void run(){ |soDt<y+L
long now = System.currentTimeMillis(); V'alzw7#
if ((now - lastExecuteTime) > executeSep) { S+9}W/
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6N+ ]g/_a
//System.out.print(" now:"+now+"\n"); s_:7dD
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); yUd>EnQna
lastExecuteTime=now; 9
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executeUpdate(); &![3{G"+>l
} ^V,?n@c!
else{ JiH^N!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p^J=*jm)x
} {B|)!_M#
} #s%_ L
} &pCa{p
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ;@/^hk{A
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类写好了,下面是在JSP中如下调用。 KUD&vqx3
d%?$UnQ
<% v%^"N_]
CountBean cb=new CountBean(); dA03,s
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); lW6$v*
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CountCache.add(cb); xfegi$
out.print(CountCache.list.size()+"<br>"); EnW}>XN
CountControl c=new CountControl(); ,r_%p<lOFu
c.run(); '/O >#1
out.print(CountCache.list.size()+"<br>"); ^W#161&
%>