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: gJOswN;([
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CountBean.java ";0-9*I
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/* wAb_fU&*
* CountData.java GEb)nHQq
* |("5 :m
* Created on 2007年1月1日, 下午4:44 hW cM.
* XnvaT(k7Y
* To change this template, choose Tools | Options and locate the template under 8{Svax(
* the Source Creation and Management node. Right-click the template and choose I#p-P)Q%S
* Open. You can then make changes to the template in the Source Editor. )./'RE+(k
*/ 6B?1d
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package com.tot.count; /_bM~g
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/** GWShv\c}
* B T{({3
* @author uqy~hY
*/ p@znmn-
public class CountBean { ^h|'\-d\
private String countType; n_] OYG>U
int countId; 483vFLnF
/** Creates a new instance of CountData */ QaEXk5>e
public CountBean() {} KQqQ@D&n
public void setCountType(String countTypes){ naB[0I&
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this.countType=countTypes; =WP}RZ{S
} m7mC
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public void setCountId(int countIds){ 2,%ne (
this.countId=countIds; ]gj@r[
} 0$49X
public String getCountType(){ b}G +7B
return countType; ]7"mt2Q=3
} 0P53dF
public int getCountId(){ &jPsdv h
return countId; gzdgnF2
} r>q`# ~
} 8i"{GGVC
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CountCache.java *XzUqK
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/* kp;MNRc
* CountCache.java e S
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* [K9q+
* Created on 2007年1月1日, 下午5:01 CnA*o 8w
* zKWi9
* To change this template, choose Tools | Options and locate the template under S"Zs'7dy`
* the Source Creation and Management node. Right-click the template and choose !8s:3]
* Open. You can then make changes to the template in the Source Editor. g-(xuR^*
*/ !p9F'7;Y<
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package com.tot.count; ;j_#,Da9<
import java.util.*; %F/tbXy{
/** 'Ph;:EMj
* ;[zx'e?!
* @author h/w- &7t
*/ 42Ffx?Qmv
public class CountCache { {5z?5i ?D
public static LinkedList list=new LinkedList(); 9hp0wi@W}
/** Creates a new instance of CountCache */ pcl_$2_
public CountCache() {} YGn:_9
public static void add(CountBean cb){ 6ensNr~ea
if(cb!=null){ `") I[h
list.add(cb); 6<~y!\4;F
} ,zyrBO0 Eq
} _bz,G"w+:
} Zd%\x[f9ck
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CountControl.java nMbV{h ,
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/* r#~6FpFVK^
* CountThread.java `4p9K
* BzUx@,
* Created on 2007年1月1日, 下午4:57 hP#&]W3:
* Mo<p+*8u:
* To change this template, choose Tools | Options and locate the template under %`\{Nxk
* the Source Creation and Management node. Right-click the template and choose gR>#LM&dG
* Open. You can then make changes to the template in the Source Editor. 6%xl}z]o
*/ e
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package com.tot.count; t-Fl"@s
import tot.db.DBUtils; wIiT
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import java.sql.*; V)Xcn'h
/** pV+;/y_
* Kj>_XaFCg!
* @author 8ksDXf`.
*/ d16PY_
public class CountControl{ \ d;Ow8%d/
private static long lastExecuteTime=0;//上次更新时间 }R'oAE}$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 yI;Qb7|^
/** Creates a new instance of CountThread */ )G|UB8]
public CountControl() {} MLb\:Ihy
public synchronized void executeUpdate(){ G j:|
Connection conn=null; \dMsv1\
PreparedStatement ps=null; [)=FZF6kG
try{ x"d*[m
conn = DBUtils.getConnection(); 3WVHI$A9
conn.setAutoCommit(false); $_UF9l0
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Q&LkST-i
for(int i=0;i<CountCache.list.size();i++){ EkBM>*W
CountBean cb=(CountBean)CountCache.list.getFirst(); GgYomR:
CountCache.list.removeFirst(); }?^G=IP4(
ps.setInt(1, cb.getCountId()); Z~g qTB]H
ps.executeUpdate();⑴ DQ}]'*@?
//ps.addBatch();⑵ iB`m!g6$
} oAx0$]+%V)
//int [] counts = ps.executeBatch();⑶ YD%Kd&es
conn.commit(); +Lr0i_al
}catch(Exception e){ N!3f1d7RQ
e.printStackTrace(); ;vx9xs?6
} finally{ HTG;'$H^
try{ /P%:u0fX,
if(ps!=null) { dd+).*
ps.clearParameters(); xVPGlU
ps.close(); b6(yyYdF
ps=null; BkF[nL*|
} G~Sfpf
}catch(SQLException e){} re*/JkDq3K
DBUtils.closeConnection(conn); V]2z5u_q
} kShniN
} ^pP
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public long getLast(){ gs3}rW
return lastExecuteTime; A.FI] K@
} 73.b9mF
public void run(){ m~K]|]iqQ
long now = System.currentTimeMillis(); zl[JnVF\6
if ((now - lastExecuteTime) > executeSep) { CAA~VEUL
//System.out.print("lastExecuteTime:"+lastExecuteTime); #@fypCc
//System.out.print(" now:"+now+"\n"); gr=`_k4~1
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); XTJ>y@
lastExecuteTime=now; vX\e*
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executeUpdate(); m @%|Q;
} wMoAvA_oS
else{ @!da1jN
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); +*q@= P,
} /~[R
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} >>r:L3 <!
} *Y ZLQT
//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 v#FUD-Z
AngwBZ@
类写好了,下面是在JSP中如下调用。 ._Xtb,p{
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<% c"ztrKQQ
CountBean cb=new CountBean(); 'Ap5Aq
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \YS?}! 0
CountCache.add(cb); nz\fN?q
out.print(CountCache.list.size()+"<br>"); rWXW}Yg
CountControl c=new CountControl(); |9I;`{@
c.run(); Tjqn::~D
out.print(CountCache.list.size()+"<br>"); bph*X{lFK
%>