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: aF D="Zh
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CountBean.java S/a/1n$ U
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/* 929#Q#TT
* CountData.java xg(<oDn+\
* ;
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* Created on 2007年1月1日, 下午4:44 60~v
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* S|l&fb n
* To change this template, choose Tools | Options and locate the template under UP\8w#~
* the Source Creation and Management node. Right-click the template and choose {;U} :Dx
* Open. You can then make changes to the template in the Source Editor. w+Ad$4Pf"
*/ G"}qV%"6"
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package com.tot.count; i:g{{Uuv
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/** }'u3U"9)
* 6!*K/2:O
* @author H!p!sn
*/ %(fL?
public class CountBean { |d5ggf.w
private String countType; LOe4c0C6Ca
int countId; uRP
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/** Creates a new instance of CountData */ 2q12yY f
public CountBean() {} N0]z/}hd@
public void setCountType(String countTypes){ B<A:_'g
this.countType=countTypes; _wMc*kjJO
} mG
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public void setCountId(int countIds){ P<8LAc$T
this.countId=countIds; yxqTm%?y
} HS7R lU^
public String getCountType(){ MY&<)|v\
return countType; TV<Aj"xw
} pH^ z
public int getCountId(){ b7Yq_%+
return countId; %cS#+aK6M'
} aWdUuid
} nZe\5`
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CountCache.java =+`D
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/* r8sdzz%
* CountCache.java 0(\p<qq
* @sN^BX`z
* Created on 2007年1月1日, 下午5:01 8:~b
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* ZHz^S)o\[s
* To change this template, choose Tools | Options and locate the template under *JwFD^<j
* the Source Creation and Management node. Right-click the template and choose 9wzwY[{
* Open. You can then make changes to the template in the Source Editor. jn~!V!++
*/ f;R>Pr;rD
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package com.tot.count; )4PB<[u
import java.util.*; So?m?,!W
/** iW'_R{)T
* f]c<9Q>*
* @author 3=IG#6)~C
*/ -7&?@M,u
public class CountCache { A^8x1ydZ
public static LinkedList list=new LinkedList(); JXL'\De ;
/** Creates a new instance of CountCache */ f0OgK<.>T
public CountCache() {} pVY4q0@
public static void add(CountBean cb){ vpi l$Uq
if(cb!=null){ RTZ:U@
list.add(cb); uO"y`$C$_
} Gj)uyjct
} `6UtxJSx
} [Q|M/|mnR1
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CountControl.java l`* ( f9Q
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/* }Iip+URG
* CountThread.java .ByU
* w?*jdwh,'
* Created on 2007年1月1日, 下午4:57 i]dz}= j'
* vsc&Ju%k
* To change this template, choose Tools | Options and locate the template under Jb9F=s+
* the Source Creation and Management node. Right-click the template and choose L*9H#%3
* Open. You can then make changes to the template in the Source Editor. j6HR&vIM
*/ 8sH50jeP
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package com.tot.count; my4\mi6P
import tot.db.DBUtils; T30Zk*V
import java.sql.*; Z~_8P
/** an. `dBm
* 'Wtf>`
* @author vkuc8 li
*/ vcwK6G
public class CountControl{ ?3Pazc]+|
private static long lastExecuteTime=0;//上次更新时间 IKo;9|2U
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 p0Z:Wkz]
/** Creates a new instance of CountThread */ r,Ds[s)B
public CountControl() {} lJUy;yp_+
public synchronized void executeUpdate(){ #3.\j"b
Connection conn=null; 8ZW?|-i
PreparedStatement ps=null; "Tv:*L5
try{ GyuV
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conn = DBUtils.getConnection(); j3{HkcjJG
conn.setAutoCommit(false); &kiF/F 1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 0d";Hh:
for(int i=0;i<CountCache.list.size();i++){ 2uEhOi0I
CountBean cb=(CountBean)CountCache.list.getFirst(); O2% ` 2h
CountCache.list.removeFirst(); Co[n--@C
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ $
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//ps.addBatch();⑵ -~\f2'Q
} BJgDo
//int [] counts = ps.executeBatch();⑶ F3Dt7q
conn.commit(); S~> 5INud
}catch(Exception e){ yhwy>12,K
e.printStackTrace(); P:^=m*d
} finally{ 7
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try{ ~#q;bS
if(ps!=null) { *Q5x1!#z#
ps.clearParameters(); Z}+yI,
ps.close(); 6"+8M 3M l
ps=null; /BT1oWi1y
} =U
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}catch(SQLException e){} <wa(xDBw
DBUtils.closeConnection(conn); `36N
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} k2.G%]j
} <6R"h-u"
public long getLast(){ R1/q3x
return lastExecuteTime; JjQVzkE
} xDUaHE1co
public void run(){ P5Dk63z]
long now = System.currentTimeMillis(); AEqq1A
if ((now - lastExecuteTime) > executeSep) { y?Onb3%
//System.out.print("lastExecuteTime:"+lastExecuteTime); 4'm q_o#4W
//System.out.print(" now:"+now+"\n"); vd(dNu&,<
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); x W\,KSK
lastExecuteTime=now; vK:QX$b
executeUpdate(); tt{`\1q
} nj
else{ E(;i>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); x2m]Us@LIU
} LipxAE?O
} &[~[~m|
} `.8UKSH+
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 V^2-_V]8
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类写好了,下面是在JSP中如下调用。 8YKQItK
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<% [ f34a
CountBean cb=new CountBean(); ^K;hn,R=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); Pin/qp&Fa8
CountCache.add(cb); "{ FoA3g|
out.print(CountCache.list.size()+"<br>"); yd*3)6=
CountControl c=new CountControl(); JGgxAd{L
c.run(); B9^R8|V
out.print(CountCache.list.size()+"<br>"); jA<T p}$!
%>