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: YaY8 `M{
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CountBean.java @"|i"Hk^
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/* IA*KaX2S<
* CountData.java x?r1s#88>
* K7`YJp`i
* Created on 2007年1月1日, 下午4:44 P $>`
* ?tYpc_p#
* To change this template, choose Tools | Options and locate the template under UAYd?r
* the Source Creation and Management node. Right-click the template and choose rwqv V^
* Open. You can then make changes to the template in the Source Editor. / 8gL.i$
*/ &35|16z%@
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package com.tot.count; UG[e//m
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/** #DI$Oc
* v[S-Pi1
* @author 'Ud|Ex@A9
*/ 3/goCg
public class CountBean { >3D7tK(
private String countType;
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int countId; LSd*|3E}n
/** Creates a new instance of CountData */ 8cVzFFQP
public CountBean() {} 5EeDHsvV9
public void setCountType(String countTypes){ yA7)Y})>
this.countType=countTypes; 5lmO:G1
} H\G{3.T.9
public void setCountId(int countIds){ jqcz\n d
this.countId=countIds; /"#4T^7&
} (ku5WWJ
public String getCountType(){ ;vp\YIeX1
return countType; SUdm 0y
} >Da~Q WW|
public int getCountId(){ M##';x0
return countId; w|Aqqe
} uJow7-FD
} m],Ud\
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CountCache.java )]Ti>R O7
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/* HW_& !ye
* CountCache.java R>)MiHcCg
* 3 <SqoJSp
* Created on 2007年1月1日, 下午5:01 y]
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* 'K@0Wp
* To change this template, choose Tools | Options and locate the template under _sMs}?^
* the Source Creation and Management node. Right-click the template and choose "Pc$\zJm;
* Open. You can then make changes to the template in the Source Editor. [ygF0-3ND
*/ +m$5a
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package com.tot.count; mJ
import java.util.*; 2WCLS{@'
/** 79Bg]~}Z
* ?y7w} W
* @author 3<(q }
*/ >Hwc,j
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public class CountCache { LtKB v4
public static LinkedList list=new LinkedList(); tIZ~^*'
/** Creates a new instance of CountCache */ :@. ;
public CountCache() {} WS0JS'
public static void add(CountBean cb){ TT}]wZ
if(cb!=null){ T] | d5E
list.add(cb); +]!lS7nsW
} \2!!L=&4G
} ;#anZC;
} :BZ0 7`9
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CountControl.java S`q%ypy
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/* _
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* CountThread.java <n0{7#PDqw
* hKe30#:v
* Created on 2007年1月1日, 下午4:57 yfe'>]7
* %%}A|,
* To change this template, choose Tools | Options and locate the template under ^gR+S
* the Source Creation and Management node. Right-click the template and choose ]qktj=p
* Open. You can then make changes to the template in the Source Editor. l\Ftr_Dk
*/ Wd 2sh
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package com.tot.count; gR gog*z
import tot.db.DBUtils; Px;Cg
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import java.sql.*; ;u-4KK
/** v.g"{us
* k*$3i
* @author Z[L5 ;
*/ M7dU@ Ag
public class CountControl{ i@$*Csj\9*
private static long lastExecuteTime=0;//上次更新时间 _"N\b%CkO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !`wW_W
/** Creates a new instance of CountThread */ Faac]5u:*
public CountControl() {} "QY1.:o<(
public synchronized void executeUpdate(){ 9]yW_]P
Connection conn=null; [_!O<z_sB
PreparedStatement ps=null; E`D%PEps+
try{ b`~wGe
conn = DBUtils.getConnection(); +!O-kd
conn.setAutoCommit(false); p^QZ q>v
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W|UtY`1
for(int i=0;i<CountCache.list.size();i++){ D<):ZfUbI
CountBean cb=(CountBean)CountCache.list.getFirst(); shFc[A,r}
CountCache.list.removeFirst(); <d7xt*4
ps.setInt(1, cb.getCountId()); =!0I_L/
ps.executeUpdate();⑴ ;#QhQx
//ps.addBatch();⑵ &O1v,$}'
} (FVX57
//int [] counts = ps.executeBatch();⑶ * gqSWQ
conn.commit(); Pv){sYUh
}catch(Exception e){ j}WByaZ&
e.printStackTrace(); h4`9Cfrq ,
} finally{ tYe:z:7l?<
try{ v 81rfB5
if(ps!=null) { 'gTmH [be
ps.clearParameters(); NPJ.+ph
ps.close(); (6qsKX
ps=null; ;e{5)@h$
} @.$MzPQQI
}catch(SQLException e){} );JJ2Jlkd
DBUtils.closeConnection(conn); -
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} 8;zDg$(
} SG'JE}jzO
public long getLast(){ a G27%(@
return lastExecuteTime; ImkrV{,e
} ]0~qi@
public void run(){ bBE+jqi2
long now = System.currentTimeMillis(); Y1\K;;X
if ((now - lastExecuteTime) > executeSep) { r6Nm!Bq7
//System.out.print("lastExecuteTime:"+lastExecuteTime); 2$0)?ZC?=
//System.out.print(" now:"+now+"\n"); }Ik1bkK
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Q,e*#oK3$
lastExecuteTime=now; WZ~> BM
executeUpdate(); fI:H8
} ($d4:Ww
else{ Ps>&"k$T
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); kC$I2[ t!
} O|z%DkH[
} |C-y}iQ:6~
} :5#
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//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 >BoSw&T$Q
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类写好了,下面是在JSP中如下调用。 ~@9zil41
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<% %$9bce-fcG
CountBean cb=new CountBean(); <DmTj$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^.HWkS`e
CountCache.add(cb); c> ~:dcy
out.print(CountCache.list.size()+"<br>"); P. V\ov7m2
CountControl c=new CountControl(); .6 T4 z7I
c.run(); 8pe0$r`b
out.print(CountCache.list.size()+"<br>"); !Q)3-u
%>