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: fC(lY4,H3R
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CountBean.java ~LkReQI
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/* lOZ.{0{f,
* CountData.java )u[2TI1
* mp@ JsCU
* Created on 2007年1月1日, 下午4:44 '+-R 7#
* ~~kIA"U
* To change this template, choose Tools | Options and locate the template under lr^-
* the Source Creation and Management node. Right-click the template and choose ts)0+x
* Open. You can then make changes to the template in the Source Editor. KWXJ[#E<W
*/ vA+ RZ
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package com.tot.count; s{A-K5S
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/** -4X,x
* s31^9a
* @author 0Z9jlwcQ
*/ Nz$OD_]
public class CountBean { ]=h
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private String countType; in B}ydk
int countId; - FE)
/** Creates a new instance of CountData */
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public CountBean() {} orTTjV]_m
public void setCountType(String countTypes){ i?|K+"=D
this.countType=countTypes; yP[GU| >(
} OE:t!66
public void setCountId(int countIds){ 8l)l9;4 6
this.countId=countIds; l;?.YtMg
} I]
public String getCountType(){ tD>m%1'&
return countType; ^hbh|Du
} A7:
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public int getCountId(){ TTqOAo[-Z
return countId; BRH:5h
} v[lytX4)
} 8t6h^uQ
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CountCache.java + E S.O]?>
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/* =OjzBiHR
* CountCache.java Q~*A`h#
* 6W#+U<
* Created on 2007年1月1日, 下午5:01 %DRDe
* s
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* To change this template, choose Tools | Options and locate the template under Fs&m'g
* the Source Creation and Management node. Right-click the template and choose Vy(lyD<6
* Open. You can then make changes to the template in the Source Editor. ',O@0L]L
*/ e348^S&rG
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package com.tot.count; E}a3. 6)p
import java.util.*; $p9XXZ"*
/** 9jvg[H
* Y,)9{T
* @author W>@+H"pZ
*/ O|gb{
public class CountCache { iPkG=*Ip(%
public static LinkedList list=new LinkedList(); r
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/** Creates a new instance of CountCache */ X;}_[=-
public CountCache() {} fA+M/}=
public static void add(CountBean cb){ z?7s'2w&{
if(cb!=null){ zV2c`he%z
list.add(cb); [s7I.rdGzz
} |-e=P9,
} />n0&~k[h
} se)I2T{J
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CountControl.java }f({03$
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/* {8"W
* CountThread.java J4co@=AJ
* #b8/gRfS
* Created on 2007年1月1日, 下午4:57
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* r[\47cG
* To change this template, choose Tools | Options and locate the template under ^Xb!dnT.*a
* the Source Creation and Management node. Right-click the template and choose *Pq`~W_M7
* Open. You can then make changes to the template in the Source Editor. s5z@`M5'm
*/ C8{CKrVE
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package com.tot.count; _VM J q9.
import tot.db.DBUtils; j}ruXg
import java.sql.*; ~S=hxKI
/** j#~4JGZt
* ")o.x7~N
* @author :Mt/6}
*/ h{TnvI/"
public class CountControl{ _c #P
private static long lastExecuteTime=0;//上次更新时间 RP(FV<ot
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `[ne<F?e
/** Creates a new instance of CountThread */ _wqFKj
public CountControl() {} ?pxx,o6l
public synchronized void executeUpdate(){ @B[=`9KF[
Connection conn=null; uZ'5&k96T
PreparedStatement ps=null; ll5Kd=3
try{ E3KPjK
conn = DBUtils.getConnection(); )lW<:?k
conn.setAutoCommit(false); +nqOP3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @{$SjR8Q $
for(int i=0;i<CountCache.list.size();i++){ @lBH@HR=C
CountBean cb=(CountBean)CountCache.list.getFirst(); %_3{Db`R>
CountCache.list.removeFirst(); "5YsBih
ps.setInt(1, cb.getCountId()); 4mPg; n
ps.executeUpdate();⑴ Fm2t:,=
//ps.addBatch();⑵ v=L^jw
} , n
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//int [] counts = ps.executeBatch();⑶ {fS/ZG"5<t
conn.commit(); 2s(K4~e e
}catch(Exception e){ JEAqSZak#
e.printStackTrace(); Nls|R
} finally{ ~7Jc;y&
try{ ,Wdyg8&.
if(ps!=null) { }wUF#
ps.clearParameters(); b>waxQxjS
ps.close(); &2c?g1%
ps=null; BzgDhDj
} = F:d#j>F
}catch(SQLException e){} zU}0AVlIL:
DBUtils.closeConnection(conn); Cvl"")ZZ`
} lvFHr}W
} U 26Iz
public long getLast(){ ,v^it+Jc'
return lastExecuteTime; 9:esj{X
} FB</~
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public void run(){ -MU^%t;-
long now = System.currentTimeMillis(); \@80Z5?n
if ((now - lastExecuteTime) > executeSep) { Uh7kB`2
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7sFjO/a*
//System.out.print(" now:"+now+"\n"); ?^6RFbke+
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Eu0_/{:
lastExecuteTime=now; LOOv8'%O8
executeUpdate(); @ 8SYV}0H
} [NuayO3
else{ AFY;;_Xks
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Cx@, J\rsQ
} PgxU;N7Y
} S[%86(,*gP
} `5gcc7b
//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 f:=?"MX7
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类写好了,下面是在JSP中如下调用。 {0[qERj"z
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<% ]~|zY5i!
CountBean cb=new CountBean(); }$OQw'L[
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); s^E%Ukm
CountCache.add(cb); oinF<-(
out.print(CountCache.list.size()+"<br>"); .m4K ]^m
CountControl c=new CountControl(); ")8wu1V-
c.run(); Yr0%ZYfN
out.print(CountCache.list.size()+"<br>"); p;C`n)7P7
%>