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: c<imqDf
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CountBean.java jYnP)xX;
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/* ]vZ}4Xno
* CountData.java M
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* "rR$2`v"
* Created on 2007年1月1日, 下午4:44 BD&AtOj[,
* Fz^5cxmw
* To change this template, choose Tools | Options and locate the template under V5S6?V\
* the Source Creation and Management node. Right-click the template and choose !b'!7p
* Open. You can then make changes to the template in the Source Editor. (]sk3
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*/ R/kfbV-b
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package com.tot.count; Zr$D\(hX
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/** PvVn}i
* XseP[
* @author [A#>G4a<
*/ 7WEoyd
public class CountBean { t[X,m]SX
private String countType; Sbjc8V ut
int countId; PAs.T4Av^
/** Creates a new instance of CountData */ R6qC0@*
public CountBean() {} 2GJp`2(%dA
public void setCountType(String countTypes){ AqjEz+TVt
this.countType=countTypes; s
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} SaiYdJ
public void setCountId(int countIds){ s^ K:cz
this.countId=countIds; J9XV:)Yv#
} mZ4I}_\,
public String getCountType(){ yvV]|B@sO
return countType; 1L<X+,]@
} G33'Cgo:,
public int getCountId(){ !E_RD,_
return countId; gbN@EJ
} %e1`wMa
} SOQR(UT
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CountCache.java ki9vJ<
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/* J|N>}di
* CountCache.java n/Dk~Q)
* `g:bvIV5x>
* Created on 2007年1月1日, 下午5:01 8|-064i>
* 95oh}c
* To change this template, choose Tools | Options and locate the template under d6{0[T^L
* the Source Creation and Management node. Right-click the template and choose y\}<N6
* Open. You can then make changes to the template in the Source Editor. l#;o^H i
*/ @rxfOc0J#
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package com.tot.count; 1zc-$B`t
import java.util.*; m'5rzZP
/** <R8!fc{`
* x<h-F
* @author $iOkn|~<@W
*/ e7JZk6GP#9
public class CountCache { rI4N3d;C
public static LinkedList list=new LinkedList(); uqK[p^{
/** Creates a new instance of CountCache */ fg~9{1B
public CountCache() {} h"ko4b3^'@
public static void add(CountBean cb){ j8{,u6w)-
if(cb!=null){
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list.add(cb); F+::UWKA
} E/uKzzD9
} aXyg`CDv
} 5'"l0EuD
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CountControl.java ~VaO,8&+L
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/* C_
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* CountThread.java N1jJ(}{3
* ,)P6fa/
* Created on 2007年1月1日, 下午4:57 K 6HH_T
* =B tmi
* To change this template, choose Tools | Options and locate the template under c`4i#R
* the Source Creation and Management node. Right-click the template and choose 4@* `V
* Open. You can then make changes to the template in the Source Editor. MU5#ph
*/ 0O7VM)[
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package com.tot.count; rklK=W z
import tot.db.DBUtils; b2HHoIT
import java.sql.*; C4
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/** hYv;*]
* bB"q0{9G-
* @author qlIbnyP<
*/ GXx/pBdy[4
public class CountControl{ iJ 8I#
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private static long lastExecuteTime=0;//上次更新时间 \[;Qqn0
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 3M<T}>
/** Creates a new instance of CountThread */ b1frAA
public CountControl() {} i 79;;9M
public synchronized void executeUpdate(){ 8WL*Pr1I
Connection conn=null; o9L$B
PreparedStatement ps=null; ~4[4"Pi>|
try{ !:w&eFC6
conn = DBUtils.getConnection(); Wf!<Qot|R#
conn.setAutoCommit(false); Y)OTvKrOA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); LwS>jNJx
for(int i=0;i<CountCache.list.size();i++){ M>"J5yqR
CountBean cb=(CountBean)CountCache.list.getFirst(); 8n Oent0a
CountCache.list.removeFirst(); {\zB'SNq
ps.setInt(1, cb.getCountId()); Jb"0P`senY
ps.executeUpdate();⑴ yZDS>7H
//ps.addBatch();⑵ pG9qD2Cf
} 30nR2mB
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//int [] counts = ps.executeBatch();⑶ wf=M|
#}_
conn.commit(); 3rQ;}<*M
}catch(Exception e){ g7nqe~`{
e.printStackTrace(); 6qzy eli
} finally{ 6I,4 6 XZ-
try{ iH[ .u{h
if(ps!=null) { #ZvDf5A
ps.clearParameters(); T*8rR"
ps.close(); Uv"O'Z
ps=null; [^GXHE=
} TBp$S=_**
}catch(SQLException e){} rytaC(
DBUtils.closeConnection(conn); Af{K#R8!
} !$|h[ct
} o
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public long getLast(){ &[iunJv:eq
return lastExecuteTime; 8ECBi(
} @&LtIN#
public void run(){ %44Z7
long now = System.currentTimeMillis(); WjsE#9D!of
if ((now - lastExecuteTime) > executeSep) { A~7q=-
//System.out.print("lastExecuteTime:"+lastExecuteTime); 0-a[[hL?
//System.out.print(" now:"+now+"\n"); 3a\.s9A"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zQhc
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lastExecuteTime=now; h`:f
executeUpdate(); I&Y9
} li
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else{ p^ojhrr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); '}eA2Q>BV
} S((\KL,
} ( [m[<
} )/2J|LxS
//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 2or!v^^u
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类写好了,下面是在JSP中如下调用。 /6Vn WrN_
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<% n.\|NR'v
CountBean cb=new CountBean(); ?g\SF}2
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7o5~J)qIC
CountCache.add(cb); JK@"
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out.print(CountCache.list.size()+"<br>"); <.qhW^>X
CountControl c=new CountControl(); R"
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c.run(); s@c.nT%BYL
out.print(CountCache.list.size()+"<br>"); L-v-KO6
%>