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: ;`j/D@H
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CountBean.java h0 |}TV^UJ
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/* 2W<n5o
* CountData.java <z)m%*lvU
* g.DLfwI|
* Created on 2007年1月1日, 下午4:44 qRB7Ec_
* DtxE@,
* To change this template, choose Tools | Options and locate the template under )P
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* the Source Creation and Management node. Right-click the template and choose |\9TvN^$`
* Open. You can then make changes to the template in the Source Editor. t;q7t!sC]
*/ nvq3*
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package com.tot.count; :}}%#/nd
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/** |(R5e
* Zj9c9
* @author C*kK)6v`
*/ x~DLW1I
public class CountBean { C"V%# K
private String countType; qYB~VE03
int countId;
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/** Creates a new instance of CountData */ =t0tK}Y+4
public CountBean() {} 7(k^a)~PL
public void setCountType(String countTypes){ 4`v!Z#e/aX
this.countType=countTypes; LDj<?'
} oOU1{[
public void setCountId(int countIds){ Pcd *">v
this.countId=countIds; WrGK \Vw[
} jA(vTR.`
public String getCountType(){ Ty4S~ClO#'
return countType; WCq
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} b~Y%gC)FR
public int getCountId(){ 4vZ4/#(x
return countId; N3A<:%s
} LEW hb!U
} #;VA5<M8
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CountCache.java |i%2%V#
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/* &Z("D7.G
* CountCache.java EMvHFu
* ,XKCz ]8V
* Created on 2007年1月1日, 下午5:01 HTjkR*E
* B|Wk?w.{r\
* To change this template, choose Tools | Options and locate the template under : 3ZYJW1
* the Source Creation and Management node. Right-click the template and choose $K}DB N; 4
* Open. You can then make changes to the template in the Source Editor. DT(d@upH
*/ " {dek
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package com.tot.count; o+ O}Te
import java.util.*; S]/b\B.h+
/** n%%7KTqu
* ?;ukvD
* @author Zk-~ar
*/ hlJpElYf
public class CountCache { fC-P.:F#I
public static LinkedList list=new LinkedList(); $hrIO+
/** Creates a new instance of CountCache */ cWAtju?L;
public CountCache() {} P87#
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public static void add(CountBean cb){ )q~DTR^z-
if(cb!=null){ C}}/)BYi
list.add(cb); 0DPxW8Y -`
} sp9W?IJ 6c
}
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CountControl.java U7$WiPTNL9
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/* a|j%n
* CountThread.java 0S/'
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* fRZ KEIyk
* Created on 2007年1月1日, 下午4:57 ^-)txC5{T
* ?}p:J{
* To change this template, choose Tools | Options and locate the template under nA7M8HB
* the Source Creation and Management node. Right-click the template and choose pf" <!O[
* Open. You can then make changes to the template in the Source Editor. AG6K
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*/ 5r,r%{@K
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package com.tot.count; 8AFczeg[[
import tot.db.DBUtils; 3)Ac"nuyqH
import java.sql.*; IND ]j72
/** i&Fiq&V)[
* m}j:nk
* @author dR^"X3$
*/ I~*
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public class CountControl{ (<*e
private static long lastExecuteTime=0;//上次更新时间 El2e~l9
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BHFY%6J!
/** Creates a new instance of CountThread */ }CGSEr4'w~
public CountControl() {} Cr ?4Ngw
public synchronized void executeUpdate(){ v}JD2.O+
Connection conn=null; yzsab ^]
PreparedStatement ps=null; +/{L#e>
try{ H1:be.^YP
conn = DBUtils.getConnection(); 6i@\5}m=
conn.setAutoCommit(false); Vy<HA*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); -Sv"gLB
for(int i=0;i<CountCache.list.size();i++){ o:q1beU
CountBean cb=(CountBean)CountCache.list.getFirst(); t~7V{ xk
CountCache.list.removeFirst(); z;\d L
ps.setInt(1, cb.getCountId()); bO5k6i
ps.executeUpdate();⑴ w(d>HHg
//ps.addBatch();⑵ L5YnG_M&
} Ucw yxXI
//int [] counts = ps.executeBatch();⑶ _Xcn
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conn.commit(); `\u;K9S6
}catch(Exception e){
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e.printStackTrace(); [V8fu
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} finally{ E-5_{sc
try{ E ]9\R
if(ps!=null) { F/c$v
ps.clearParameters(); d@C&+#QDF
ps.close(); ./6<r OW
ps=null; 0C%W&;r0
} AV8T
}catch(SQLException e){} |Hr:S":9
DBUtils.closeConnection(conn); po9
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} Z)9g~g94
} FCj{AD
public long getLast(){ &;TJ~r#K
return lastExecuteTime; u6u=2
} w~R`D
public void run(){ MxQ?Sb%Gka
long now = System.currentTimeMillis(); [4&#*@
if ((now - lastExecuteTime) > executeSep) { eW'2AT?2H%
//System.out.print("lastExecuteTime:"+lastExecuteTime); Os%n{_#8
//System.out.print(" now:"+now+"\n"); qml2XJ>
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); BQ</g* $;
lastExecuteTime=now; D('2p8;2"7
executeUpdate(); Z;Rp+X
} G2{O9
else{ [%A4]QzWh
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?(6m VyIe
} C#V ~Y
} /Dtd#OAdr
} \VMD$zZx
//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 Ty(@+M~-
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类写好了,下面是在JSP中如下调用。 [Qt?W gPj
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<% -5l6&Y
CountBean cb=new CountBean(); lfsqC};#\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); HL3XyP7
CountCache.add(cb); qm*}U3K
out.print(CountCache.list.size()+"<br>"); .9[45][FK
CountControl c=new CountControl(); wd@aw /
c.run(); 8e~|.wOL
out.print(CountCache.list.size()+"<br>"); g?v\!/~(u
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