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: :}#)ipr
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CountBean.java >tMI%r
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/* oz]3
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* CountData.java 0cfGI%
* :6(@P1vA 6
* Created on 2007年1月1日, 下午4:44 <f.Eog
* >e-0A
* To change this template, choose Tools | Options and locate the template under E^{!B]/oP
* the Source Creation and Management node. Right-click the template and choose GZx*A S]+
* Open. You can then make changes to the template in the Source Editor. "8?Fl&=Q
*/ PC255
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package com.tot.count; Gi@c`lRd1
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/** up8d3
* 6'uCwAQU
* @author Tu}EAr
*/ bJ6C7-w:wa
public class CountBean { ,|zzq@fk
private String countType; d2U?rw_
int countId; ^ )!eiM
/** Creates a new instance of CountData */ c8Q2H
public CountBean() {} 5{DwD{Q
public void setCountType(String countTypes){ @6R6.i5d
this.countType=countTypes; DYIp2-K
} sy4Nm0m
public void setCountId(int countIds){ `0_
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this.countId=countIds; t"J{qfNs
} h|Qb:zEP,
public String getCountType(){ ~d\V>
return countType; 3'A0{(b
} =;I+:K
public int getCountId(){ &AeNrtGu
return countId; ~FXq%-J
} MwQt/Qv=
} D Vg$rm`
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CountCache.java P&:[pPG
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/* .EjR<UU
* CountCache.java "j8=%J{
* H=Cj/jE
* Created on 2007年1月1日, 下午5:01 SG0PQ
* ln,9v
* To change this template, choose Tools | Options and locate the template under v*As:;D_
* the Source Creation and Management node. Right-click the template and choose W| 0))5a
* Open. You can then make changes to the template in the Source Editor. }ksp(.}G
*/ x7i<dg&
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package com.tot.count; iG~&uEAJ
import java.util.*; ,PJC FQMR
/** : vgn0IQ
* kG}F/GN?
* @author nf&5oE^
*/ q.@% H}
public class CountCache { 3qH1\
public static LinkedList list=new LinkedList(); cyabqx
/** Creates a new instance of CountCache */ ke<5]&x
public CountCache() {} [>3dhj[;
public static void add(CountBean cb){ cF9oo%3
if(cb!=null){ (mI590`f
list.add(cb); \"Z\Af<
} kr
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} `cN8AcRHP
} vv^y
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CountControl.java 5gC>j(
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/* &0%B3
* CountThread.java ORWi+H|
* ryA+Lli.
* Created on 2007年1月1日, 下午4:57 =d:3]M^
* >NV1#\5_R@
* To change this template, choose Tools | Options and locate the template under g4 +Hq *
* the Source Creation and Management node. Right-click the template and choose .ns=jp
* Open. You can then make changes to the template in the Source Editor. Bm%|WQK
*/ y>gw@+
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package com.tot.count; + DE/DR:
import tot.db.DBUtils; ^~@3X[No
import java.sql.*; EdSUBoWF}
/** p1HbD`ST
* ,\#s_N7
* @author y"U)&1 c%
*/ NZ6:ZzM
public class CountControl{ {{gt>"D,
private static long lastExecuteTime=0;//上次更新时间 `P*BW,P'T
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g)|vS>^~
/** Creates a new instance of CountThread */ Vx>Q
public CountControl() {} C-h?#/#?y
public synchronized void executeUpdate(){ . n)R@&9
Connection conn=null; CQrP%}`r
PreparedStatement ps=null; DxpJP,wY3
try{ ,\aLv
conn = DBUtils.getConnection(); d\JBjT1g
conn.setAutoCommit(false); uZ>q$
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Ck"db30.
for(int i=0;i<CountCache.list.size();i++){ ux|
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CountBean cb=(CountBean)CountCache.list.getFirst(); "Ehh9 m1&
CountCache.list.removeFirst(); <8Nr;96IA
ps.setInt(1, cb.getCountId()); f\.y z[
ps.executeUpdate();⑴ DQc\[Gq&
//ps.addBatch();⑵ yx:+Xy*N
} 6iF&!Fd>J
//int [] counts = ps.executeBatch();⑶
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conn.commit(); B
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}catch(Exception e){ |_-w{2K
e.printStackTrace(); dG]B-(WTC
} finally{ lQvgq
try{ gFu,q`Vf*
if(ps!=null) { g;nLR<]
ps.clearParameters(); o76!7
ps.close(); M* Ej*#
ps=null; 3
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} HIvSpO
}catch(SQLException e){} XuHR
DBUtils.closeConnection(conn); kS9;Tj cx
} !IO\g"y~|%
} KRcB_(
public long getLast(){ M6^
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return lastExecuteTime; ?_A[E]/H
} CYwV]lq:s
public void run(){ )cZHBG.0H
long now = System.currentTimeMillis(); P3Lsfi.
if ((now - lastExecuteTime) > executeSep) { 'g'RXC}D>
//System.out.print("lastExecuteTime:"+lastExecuteTime); /~f[>#
//System.out.print(" now:"+now+"\n"); |O oczYf
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); RjPkH$u'Pj
lastExecuteTime=now; bDJ!Fc/
executeUpdate(); _;Xlw{FN^
}
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else{ <*dcl2xS
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); :9%e:-
} xU0iz{9
} _5~|z$GW
} 5dN>Xjpu
//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 ge6S_"
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类写好了,下面是在JSP中如下调用。 lX"m|W
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<% ]Sa#g&}T>
CountBean cb=new CountBean(); ^L)3O|6c
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); bPP@
CountCache.add(cb); 0Ui_Trlc
out.print(CountCache.list.size()+"<br>"); ,Ww}xmq1H
CountControl c=new CountControl(); 7 vFmB
c.run(); I]+
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out.print(CountCache.list.size()+"<br>"); hZL!%sL7
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