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: s3Ce]MH
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CountBean.java {kH^OZ^(e
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/* j/pQSlV
* CountData.java Le
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* f {c[_OR
* Created on 2007年1月1日, 下午4:44 kte.E%.PE
* Q3q.*(#
* To change this template, choose Tools | Options and locate the template under faOWhIG
* the Source Creation and Management node. Right-click the template and choose AJd.K'=8
* Open. You can then make changes to the template in the Source Editor. *9ub.:EUwV
*/ si_HN{
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package com.tot.count; gA1in
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/** ]q7 LoH'S
* G)Bq?=P
* @author o'C.,ic?C
*/ U hhmG+
public class CountBean { ^!F5Cz 48
private String countType; o=#
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int countId; G?d,$NMo|
/** Creates a new instance of CountData */ dd7nO
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public CountBean() {} F'$S!K58
public void setCountType(String countTypes){ 4`P2FnJ?
this.countType=countTypes; O)JUY*&I5
} &E
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public void setCountId(int countIds){ ,wi=!KzX
this.countId=countIds; <?{}Bo0xG
} .^IhH|U
public String getCountType(){ \u-e\w
return countType; +()t8,S,
} @H%=%ZwpO
public int getCountId(){ *Yu\YjLPG
return countId; +Z<Q^5w@
} j~*Z7iu
} e=z_+gVm
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CountCache.java uBq3.+,x*
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/* k)K-mD``U
* CountCache.java 5 t`ap
* ^+Vk#_2Q
* Created on 2007年1月1日, 下午5:01 YQ@6innT
* J-\?,4mcP
* To change this template, choose Tools | Options and locate the template under TWR$D
* the Source Creation and Management node. Right-click the template and choose jJ"EGFa8
* Open. You can then make changes to the template in the Source Editor. s
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*/ 71" JL",
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package com.tot.count; 53t-'K0l
import java.util.*; 8Cs$NUU
/** [&qbc#L
* a950M7
* @author :6j :9lYL2
*/ *Z]WaDw
public class CountCache { /3[9{r
public static LinkedList list=new LinkedList(); ]AA%J@
/** Creates a new instance of CountCache */ s9rtXBJP
public CountCache() {} 90qj6.SQ
public static void add(CountBean cb){ yLz,V}
if(cb!=null){ )Bn>/-
list.add(cb); \;*}zX
} ^~6] 0$yJ
} pP0Vg'V
} uB<F.!3
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CountControl.java p=~h|(M|
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/* TwuX-b
* CountThread.java Lubs{-5lk
* *Cnq2=A]A
* Created on 2007年1月1日, 下午4:57 <P^hYj-swh
* mheU#&|
* To change this template, choose Tools | Options and locate the template under 1n`1o-&l-
* the Source Creation and Management node. Right-click the template and choose \5[D7}
* Open. You can then make changes to the template in the Source Editor. D=~B7b:
*/ %7]XW 2u
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package com.tot.count; 2b#(X'ob
import tot.db.DBUtils; D!RE-w92X
import java.sql.*; (}C^_q:7d
/** fNqmTRu
* 7SK3
* @author 9fuJJ3L[
*/ .IH@_iX
public class CountControl{ {b,2;w}95
private static long lastExecuteTime=0;//上次更新时间 MxgLztY
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MKe^_uF
/** Creates a new instance of CountThread */ [{@zb-h
public CountControl() {} 3@yTzaq6
public synchronized void executeUpdate(){ W ~Jzqp9g
Connection conn=null; 2>$F0
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PreparedStatement ps=null; ]<q}WjXD'
try{ G*(K UG>
conn = DBUtils.getConnection(); `.>k)=F&
conn.setAutoCommit(false); L%WME8PB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 8jjFC9Cbn0
for(int i=0;i<CountCache.list.size();i++){ *"5N>F[L
CountBean cb=(CountBean)CountCache.list.getFirst(); e?!L}^f6X
CountCache.list.removeFirst(); w#xeua|*I#
ps.setInt(1, cb.getCountId()); x[vBK8
ps.executeUpdate();⑴ ~ThVap[*
//ps.addBatch();⑵ Zlk,])9 Q
} zkh hN"bX
//int [] counts = ps.executeBatch();⑶ v_z..-7Dq+
conn.commit(); oQ%\[s$
}catch(Exception e){ |"R_-U
e.printStackTrace(); 3^\?>C7
} finally{ Z cm<Fw
try{ \L ]
if(ps!=null) { pgLtD};S
ps.clearParameters(); Har~MO?A
ps.close(); m
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ps=null; KZF0rW
} =naR{pI
}catch(SQLException e){} NfTCpA
DBUtils.closeConnection(conn); gMs+?SNHAh
} '%SR. JL
} CGC-"A/W
public long getLast(){ pcy<2UV
return lastExecuteTime; 4mN].X[,
} X*!Dc,0.k
public void run(){ w;
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long now = System.currentTimeMillis(); i iX\it$s
if ((now - lastExecuteTime) > executeSep) { %kh#{*q$
//System.out.print("lastExecuteTime:"+lastExecuteTime); WR/o
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//System.out.print(" now:"+now+"\n"); T-|9o|~z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); gB>imr#e&
lastExecuteTime=now; }bf=Ntk
executeUpdate(); (#!]fF"!x
} dGW{l]N
else{ SyK 9Is{8
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); C$<"w,
} VEj$^bpp5s
} uf)W-Er6~
} J7BFk
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//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 BXg!zW%+
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类写好了,下面是在JSP中如下调用。 bauA}3
VL+N:wb>
<% 7qe7Fl3
CountBean cb=new CountBean(); EntF@ln!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e-X HN
CountCache.add(cb); 7]Al*)
out.print(CountCache.list.size()+"<br>"); e74zR6
CountControl c=new CountControl(); %K[daXw6E8
c.run(); :O $@shV
out.print(CountCache.list.size()+"<br>"); nbI=r+
%>