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: Un@B D}@\
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CountBean.java z=<x.F
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/* Izm8
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* CountData.java y?GRxoCD"e
* {LYA?w^GT
* Created on 2007年1月1日, 下午4:44 pj;cL]L
* p)vyZY[
* To change this template, choose Tools | Options and locate the template under EQ1wyKZS2g
* the Source Creation and Management node. Right-click the template and choose GQhzQM1HS
* Open. You can then make changes to the template in the Source Editor. :A
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*/ =;!C7VS
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package com.tot.count; I&Q.MItW
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/** 4N&
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* |(N4ZmTm
* @author *X8<hYKZq
*/ vT"T*FKh:
public class CountBean { J@C8;]
private String countType; tX$%*Uy
int countId; #X'!wr|-
/** Creates a new instance of CountData */ P0uUVU=B|
public CountBean() {} @;2,TY>Di
public void setCountType(String countTypes){ 8`XpcK-0
this.countType=countTypes; zRN_`U
} 0^nnR7
public void setCountId(int countIds){ Z7%
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this.countId=countIds; W=41jw
} \_}Y4
public String getCountType(){ Qc#<RbLL
return countType; ba& \~_4
} c7X5sMM,
public int getCountId(){ b/cc\d <
return countId; b7Jk{x #u
} Q+'mBi}
} |_/q0#"
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CountCache.java sYM3&ikyHI
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/* fiqeXE?E
* CountCache.java S{gB~W
* ax0RtqtR&
* Created on 2007年1月1日, 下午5:01 :pj#t$:!
* ^_
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* To change this template, choose Tools | Options and locate the template under ^M6xRkI
* the Source Creation and Management node. Right-click the template and choose NBZFIFO<
* Open. You can then make changes to the template in the Source Editor. -:b0fKn
*/ Jj4!O3\I
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package com.tot.count; pE<dK.v6
import java.util.*; pe$"
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/** \)'s6>58|
* ts/rV#s~
* @author FB-?{78~
*/ jPU:&1(_ n
public class CountCache { $,Y\
public static LinkedList list=new LinkedList(); !4TM gM
/** Creates a new instance of CountCache */ mu`h6?v
public CountCache() {} bzD <6Z
public static void add(CountBean cb){ hi4#8W
if(cb!=null){ DjUif "v
list.add(cb); oe`t ? (U
} .E}fk,hLB
} k44sV.G4L
} L;$Gn"7~
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CountControl.java $}RBK'cr}
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/* 3*C9;Q}
* CountThread.java |pxM8g1w
* L]I ;{Y
* Created on 2007年1月1日, 下午4:57 r(-`b8ZE
* 0mk-o
* To change this template, choose Tools | Options and locate the template under %K[_;8
* the Source Creation and Management node. Right-click the template and choose I:M]#aFD
* Open. You can then make changes to the template in the Source Editor. :E'uV"j%
*/ N
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package com.tot.count; DU(QQ53
import tot.db.DBUtils; w:%3]2c
import java.sql.*; `%_ yRJd|;
/** e<o{3*%p)
* OhMnG@@
* @author '&?cW#J?
*/ e]F4w(*=
public class CountControl{ A (z
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private static long lastExecuteTime=0;//上次更新时间 t@(S=i7}-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3>;zk#b2
/** Creates a new instance of CountThread */ MQ7d IUs
public CountControl() {} bso l>M[<
public synchronized void executeUpdate(){
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Connection conn=null; M
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PreparedStatement ps=null; <Vucr
try{ JwEQR
conn = DBUtils.getConnection(); @%Y$@Qb{
conn.setAutoCommit(false); yg34b}m{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B>sSl1opI
for(int i=0;i<CountCache.list.size();i++){ 0\XG;KA
CountBean cb=(CountBean)CountCache.list.getFirst(); T=Q"|S]V
CountCache.list.removeFirst(); Mg3>/!
ps.setInt(1, cb.getCountId()); 2;X{ZLo
ps.executeUpdate();⑴ eT8(O36%
//ps.addBatch();⑵ &("HH"!
} D >ax<t1K
//int [] counts = ps.executeBatch();⑶ Hw[(v[v
conn.commit(); 1N8gH&oF
}catch(Exception e){ TY,5]*86I&
e.printStackTrace(); /4x3dwXW@
} finally{ >
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try{ $M%<i~VXe&
if(ps!=null) { W~(4t:hp
ps.clearParameters(); (
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ps.close(); x[XN;W&
ps=null; cb|cY Co5
} w0W9N%f#=
}catch(SQLException e){} pxC:VJ;
DBUtils.closeConnection(conn); R%l6+Okr
} EG=~0j ~
} <_XyHb-
public long getLast(){ JG6"5::
return lastExecuteTime; cTlitf9
} @~WSWlQW
public void run(){ ~Q<h,P
long now = System.currentTimeMillis();
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if ((now - lastExecuteTime) > executeSep) { }EFMJ,NQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); ^|Bpo(
//System.out.print(" now:"+now+"\n"); *\W
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2|a@,TW}-
lastExecuteTime=now; x@^Kd*fo
executeUpdate(); $'m&RzZ
} r(qAe{
else{ kQm\f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7,vvL8\NHu
} yx v]G6
} kC :pal
} oEfy{54
//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 H# P)n
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类写好了,下面是在JSP中如下调用。 ?[Gj?D.Wc
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<% r7dvj#^
CountBean cb=new CountBean(); -TL `nGF
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); sT&O %(
CountCache.add(cb); x[%z \
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); mC-'z
c.run(); LojEJ
out.print(CountCache.list.size()+"<br>"); ^uG^XY&ItC
%>