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: yrvSbqR
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CountBean.java X:} 5L>'
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/* 5IF~]5s
* CountData.java >=q!!'$:
* 6[Pr<4J
* Created on 2007年1月1日, 下午4:44 %_X[{(
* =w>>7u$4
* To change this template, choose Tools | Options and locate the template under 4@V <Suw
* the Source Creation and Management node. Right-click the template and choose B#V4
* Open. You can then make changes to the template in the Source Editor. m#}{"d&J
*/
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package com.tot.count; q'8@0FT0
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/** ^{]sD}Q"
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* @author d-S'y-V?d
*/ sB1tce
public class CountBean { PFn[[~5V
private String countType; 8@C|exAD`
int countId; gt~2Br4
/** Creates a new instance of CountData */ `LHfAXKN
public CountBean() {} 4sD:J-c
public void setCountType(String countTypes){ +M%2m3.Jo
this.countType=countTypes; !v;_@iW3e
} +H^V},dBp!
public void setCountId(int countIds){ qFsg&<
this.countId=countIds; o4
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} Y
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public String getCountType(){ j!8+|eAkk
return countType; {,mRMDEy
} ~X(xa
public int getCountId(){ w!9W Cl]9M
return countId; "l;8
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} xTawG?"D
} >yHnz?bf@
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CountCache.java r#Oz0=0u
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/* e ~,'|~
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* CountCache.java eJ\j{-
* `j"G=%e3.
* Created on 2007年1月1日, 下午5:01 5 9J$SE
* umn~hb5O
* To change this template, choose Tools | Options and locate the template under )PATz
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* the Source Creation and Management node. Right-click the template and choose Z1lF[d,f;
* Open. You can then make changes to the template in the Source Editor. U\GZ
*/ WsDe0F
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package com.tot.count; ]SR`96vG
import java.util.*; < 3+&DV-<N
/** h}<ZZ
* 5Cyjq0+
* @author t4c#' y
*/ imq(3?
public class CountCache { J#Ehx|
public static LinkedList list=new LinkedList(); bvRGTOxO
/** Creates a new instance of CountCache */ >"{zrwNq
public CountCache() {} YqCK#zT/
public static void add(CountBean cb){ w=>mG-
if(cb!=null){ +rO<'H:umJ
list.add(cb); 4'[ V'c\
} g-gBg\y{v
} cZT.vA#
} l5nDt$Ex
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CountControl.java yQ&%* ?J
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/* :%oj'm44!
* CountThread.java VIdoT2
* c^gIK1f-
* Created on 2007年1月1日, 下午4:57 _%%"Y}
* (>`SS#(T!
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose {YTF]J$
* Open. You can then make changes to the template in the Source Editor. kU>|E<c*
*/ trt\PP:H%
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package com.tot.count; ryLNMh
import tot.db.DBUtils; g'7hc~=
import java.sql.*; l#.,wOO{
/** RteTz_z{
*
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* @author M.^A`
*/ 80>!qG
public class CountControl{ 2![W
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private static long lastExecuteTime=0;//上次更新时间 $s!meg@s
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7V``f:#d
/** Creates a new instance of CountThread */ ,]qX_`qF
public CountControl() {} ]}y'3aW
public synchronized void executeUpdate(){ nQ3goVRFP
Connection conn=null; WN1-J(x6
PreparedStatement ps=null; C
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try{ o@;_(knb
conn = DBUtils.getConnection(); Y &+/[[
conn.setAutoCommit(false); *lO+^\HXD
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); TBT*j&!L
for(int i=0;i<CountCache.list.size();i++){ ^C|9K>M
CountBean cb=(CountBean)CountCache.list.getFirst(); _oVA0@#n
CountCache.list.removeFirst(); umn^QZ,
ps.setInt(1, cb.getCountId()); (.+n1)L?
ps.executeUpdate();⑴ B`EgL/Wg[
//ps.addBatch();⑵ uNBhVsM6<
} dF]8>jBOL
//int [] counts = ps.executeBatch();⑶ N)Kr4GC
conn.commit(); @ xr
}catch(Exception e){ 4 Z)]Cq*3
e.printStackTrace(); XnOl*#P
} finally{ U#
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try{ R/|{?:r?:x
if(ps!=null) { AE
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ps.clearParameters(); dig76D_[e
ps.close(); y@JYkp>I
ps=null; XjU; oh4:.
} @'4D9A
}catch(SQLException e){} r!iuwE@
DBUtils.closeConnection(conn); h!GixN?
} ~C
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} Tyl"N{ _
public long getLast(){ KVy5/A/8c
return lastExecuteTime; 6<nO2 GW
} X\RTHlw']
public void run(){ !YHu
long now = System.currentTimeMillis(); KL`>mJo$
if ((now - lastExecuteTime) > executeSep) { v}D!
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0MPDD%TP
//System.out.print(" now:"+now+"\n"); 0yNlf-O
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 0n=E.qZ9c
lastExecuteTime=now; Gzt5efygKt
executeUpdate(); yG4MqR)J
} r%n[PK^(
else{ TD7ONa-,
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `I$A;OPK7
} k#[s)Ja?s
} !o!04_
} gs>cx]>
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 )_?$B6hf,&
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类写好了,下面是在JSP中如下调用。 N/VIP0Kb
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<% tEs$+b
CountBean cb=new CountBean(); V.1sZYA9
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); FU3B;Fn^Z(
CountCache.add(cb); xd@DN;e
out.print(CountCache.list.size()+"<br>"); )' #(1
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CountControl c=new CountControl(); A?zW!'
c.run(); CG;D (AWR;
out.print(CountCache.list.size()+"<br>"); A>puk2 s
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