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: TZ2=O<Kj
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CountBean.java z.Y$7bf)
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/* Hd,p!_
* CountData.java !zPa_`P
* Db6om7N
* Created on 2007年1月1日, 下午4:44 xo&]RYG[<
* W2z*91$
* To change this template, choose Tools | Options and locate the template under ox%9Ph
* the Source Creation and Management node. Right-click the template and choose N_pJk2E
* Open. You can then make changes to the template in the Source Editor. 1qf!DMcdZ
*/ oiX+l5`pz
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package com.tot.count; Clh!gpB c
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/** (y M^
* >2< 8kBF_
* @author '3<fsK=
*/ ~M\I;8ne
public class CountBean { 7DIIx}A
private String countType; 4"xPr[=iG
int countId; cCa|YW^j
/** Creates a new instance of CountData */ NcP.;u;`
public CountBean() {} gS:A'@&
public void setCountType(String countTypes){ Oi:<~E[kz.
this.countType=countTypes; ?c7*_<W5
} "m ^'
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public void setCountId(int countIds){ ^`G`phd$
this.countId=countIds; TEMw8@b
} TOoQZTI
public String getCountType(){ r\blyWi
return countType; i:Zm*+Gi
} $2u 'N:o
public int getCountId(){ +e-G,%>9
return countId; JqMDqPIQ
} ZKXo-~=>
} !>>f(t4
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CountCache.java cKn`/\.H
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/* :OW;?{ ~j
* CountCache.java >5j<4ShW
*
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* Created on 2007年1月1日, 下午5:01 !YP@m~
* n_B"-n
* To change this template, choose Tools | Options and locate the template under *FmTy|
* the Source Creation and Management node. Right-click the template and choose 8X I?
* Open. You can then make changes to the template in the Source Editor. IN,(yaC
*/ v$=QA:!U
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package com.tot.count; Dc+'<"
import java.util.*; |gsE2vV
/** ]>+PnP35G
* MNg^]tpf
* @author tOOchu?=
*/ iC*F
public class CountCache { [xT:]Pw}
public static LinkedList list=new LinkedList(); EZYBeqv
/** Creates a new instance of CountCache */ 9
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public CountCache() {} 8o/}}=m$
public static void add(CountBean cb){ 5r?m&28X
if(cb!=null){ NuYkz"O]
list.add(cb); 1]}#)-
} Z(9u<
} 8HZs>l
} lhi_6&&[8
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CountControl.java tw(JZDc
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/* Raw)9tUt
* CountThread.java z.6$W^
* (?H0+zws^
* Created on 2007年1月1日, 下午4:57 &
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* YOrrkbJ(
* To change this template, choose Tools | Options and locate the template under NBF MN%
* the Source Creation and Management node. Right-click the template and choose de]z T^&C
* Open. You can then make changes to the template in the Source Editor. g/&T[FOr
*/ t!2(7=P30(
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package com.tot.count; Iu{kPyx
import tot.db.DBUtils; XTd3|Pm
import java.sql.*; f"(X(1F
/** u-1;'a
* ^{\<N()R
* @author 9<vWcq*4
*/ 1&/FG(*/
public class CountControl{ 5o/&T"]@
private static long lastExecuteTime=0;//上次更新时间 1pCieTz!PN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 6O@J7P
/** Creates a new instance of CountThread */ jA(>sz
public CountControl() {} zSE<"(a
public synchronized void executeUpdate(){ .c#y%S
Connection conn=null; rS0DSGDq
PreparedStatement ps=null; X{^}\,cVtG
try{ TyKWy0x-3
conn = DBUtils.getConnection(); 720)VzT
conn.setAutoCommit(false); Pub0IIs
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 87WBM;$&s
for(int i=0;i<CountCache.list.size();i++){ (n1Bh~R^
CountBean cb=(CountBean)CountCache.list.getFirst(); =0-
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CountCache.list.removeFirst(); xP=/N!,#
ps.setInt(1, cb.getCountId()); lKkN_ (/j
ps.executeUpdate();⑴ $O{duJU
//ps.addBatch();⑵ s!9dQ.
} |8bq>01~
//int [] counts = ps.executeBatch();⑶ O8]'o*<]
conn.commit(); OgcHS?
}catch(Exception e){ !6G?zipB
e.printStackTrace(); h b/]8mR
} finally{ X]loJoM9
try{ zyg:nKQW
if(ps!=null) { m>}8'N)
ps.clearParameters(); f,z P*
ps.close(); JxjI]SF02
ps=null; {"vkji>
} o&hIHfZri
}catch(SQLException e){} Jd,)a#<j
DBUtils.closeConnection(conn); f1PN|
} >\ u<&>i
} }YOL"<,:o
public long getLast(){ ~Z ~v
return lastExecuteTime; 1 ^g
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} |+U<S~
public void run(){ f(D_FTTO
long now = System.currentTimeMillis(); ]MtFf6&
if ((now - lastExecuteTime) > executeSep) { gq"k<C0
//System.out.print("lastExecuteTime:"+lastExecuteTime); iU+nqY'
//System.out.print(" now:"+now+"\n"); aS}1Q?cU
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); &t(0E:^TRU
lastExecuteTime=now; # tdf>?
executeUpdate(); _28<m
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} \tyg(srw0
else{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); O8U<{jgAG
} !TAp+b
} B$?qQ|0:=
} XI Jlc~2
//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 /Jf~25F
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类写好了,下面是在JSP中如下调用。 OOBhbpg!D
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<% >%Ee#m
CountBean cb=new CountBean(); >\<*4J$PZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); }]UB;id'
CountCache.add(cb); :
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out.print(CountCache.list.size()+"<br>"); U"f??y%)
CountControl c=new CountControl(); fQnwy!-\
c.run(); sP'0Sl~NU
out.print(CountCache.list.size()+"<br>"); 1\L[i];L8
%>