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: XX =A1#H
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CountBean.java E?V:dr
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/* ?Gb
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* CountData.java li'#< "R?'
* =8]'/b
* Created on 2007年1月1日, 下午4:44 +#O?sI#
* 8p5u1 ;2
* To change this template, choose Tools | Options and locate the template under <B)lV'!Bd
* the Source Creation and Management node. Right-click the template and choose QS[%`-dR2
* Open. You can then make changes to the template in the Source Editor. *N 't ;
*/ \(Iy>L.
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package com.tot.count; 3KGDS9I
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/** d(tq;2-
* W];4P=/
* @author VGSe<6Hh
*/ G 2mv6xK'
public class CountBean { D,2,4h!ka
private String countType; "|hmiMdGB
int countId; pJqayzV
/** Creates a new instance of CountData */ )|:|.`H
public CountBean() {} qYE -z(i
public void setCountType(String countTypes){ (+_Amw!W
this.countType=countTypes; ~
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} '+$2<Ys
public void setCountId(int countIds){ 7%X$6N-X
this.countId=countIds; #JVcl $0Y
} *w!H -*`
public String getCountType(){ 9 eP @} C6
return countType; r8mE
} [hs{{II
public int getCountId(){ rVkHo*Q
return countId; "UE'dWz
} UXd\Q''
} WHU&9N
.; :[sv)
CountCache.java bH&[O`vf
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/* doG&qXw
* CountCache.java )yjHABGJ
* @+\OoOK<L
* Created on 2007年1月1日, 下午5:01 $v+g3+7
* X/?3ifP6I
* To change this template, choose Tools | Options and locate the template under L./UgeZ
* the Source Creation and Management node. Right-click the template and choose Qq5)|m
* Open. You can then make changes to the template in the Source Editor. ]R0^
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*/ f F?=W
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package com.tot.count; 8Y:bvs.j
import java.util.*; C6GYhG]
/** !x>P]j7A}Y
* +&|WC2#
* @author 0%vXPlfnY
*/ $"sf%{~
public class CountCache { <jV_J+#
public static LinkedList list=new LinkedList(); 55Jk "V#8
/** Creates a new instance of CountCache */ Q|:\
public CountCache() {} mgS%YG
public static void add(CountBean cb){ GX\/2P7CZ
if(cb!=null){ " 4s,a
list.add(cb); (d_{+O"
} 07CGHAxJ`
} U:ZklDW
} ++xEMP)
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CountControl.java 9^`G `D
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/* P\SE_*&
* CountThread.java 1h|JKu0
* QGfU:
* Created on 2007年1月1日, 下午4:57 zL1H[}[z+
* fY\QI
=
* To change this template, choose Tools | Options and locate the template under #qHo+M$"
* the Source Creation and Management node. Right-click the template and choose *Bc=gl$
* Open. You can then make changes to the template in the Source Editor. RzXxnx)]q
*/ R:=i/P/
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package com.tot.count; nsYS0
import tot.db.DBUtils; &AC-?R|Dp
import java.sql.*; ;[&g`%-H<
/** a Z
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* 7|\[ipVX:3
* @author `XQM)A
*/ ,_p_p^Ar\4
public class CountControl{ aiea&aJ
private static long lastExecuteTime=0;//上次更新时间 zf#V89!]C"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !DD|dVA{
/** Creates a new instance of CountThread */ B\9ymhx;g%
public CountControl() {} 6:J @
public synchronized void executeUpdate(){ xj(&EGY:
Connection conn=null; .BZw7
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PreparedStatement ps=null; (1*?2u*j
try{ ~,.Agx
conn = DBUtils.getConnection(); TR|G4l?
conn.setAutoCommit(false); %
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); BT>8
for(int i=0;i<CountCache.list.size();i++){ Z3=t"
CountBean cb=(CountBean)CountCache.list.getFirst(); Es1Yx\/:
CountCache.list.removeFirst(); >AV?g8B;
ps.setInt(1, cb.getCountId()); -49OE*uF
ps.executeUpdate();⑴ anHP5gD
//ps.addBatch();⑵ bNj| GIf
} tvZpm@1
//int [] counts = ps.executeBatch();⑶ rJ K~kKG
conn.commit(); &!a[rvtZ+
}catch(Exception e){ .F&\xa{
e.printStackTrace(); H"6:!;9,
} finally{ P6dIU/w
try{ h$y1"!N(
if(ps!=null) { buq3t+0
ps.clearParameters(); $GPenQ~},
ps.close(); -fn["R]
ps=null; ++BVn[ 1
} ybcQ,e
}catch(SQLException e){} D:M0_4S
DBUtils.closeConnection(conn); %.[t(F
} *[k7KG2_U
} _"Y;E
public long getLast(){ Ay/ "2pDZ
return lastExecuteTime; lhKd<Y"
} 9["yL{IPe
public void run(){ 3@_je)s
long now = System.currentTimeMillis(); Jcy
if ((now - lastExecuteTime) > executeSep) { Jx(%t<2
//System.out.print("lastExecuteTime:"+lastExecuteTime); Q];+?Pu.
//System.out.print(" now:"+now+"\n"); JmtU>2z\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); w*OZ1|
lastExecuteTime=now; D\bW' k]!
executeUpdate(); i` n,{{x&4
} x4Y+?2
else{ C
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N_U Zu
}
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} 6uOR0L
} 0'% R@|
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 9co1+y=i{
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类写好了,下面是在JSP中如下调用。 Kw+?Lowp
X2/`EN\
<% s+$l.aIO!
CountBean cb=new CountBean(); %HpTQ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *4dA(N\k"
CountCache.add(cb); ~W_m<#K(
out.print(CountCache.list.size()+"<br>"); #92:h6
CountControl c=new CountControl(); [89#8|+
c.run(); : DCj2"
out.print(CountCache.list.size()+"<br>"); pTX{j=n!
%>