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: 8pDJz_F!{
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CountBean.java |MMr}]`
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/* )sB`!:~HjP
* CountData.java "C=HBJdYB5
* u[ s+YGS
* Created on 2007年1月1日, 下午4:44 \{G6!dV|S
* ^gky i/z
* To change this template, choose Tools | Options and locate the template under 5.VA1
* the Source Creation and Management node. Right-click the template and choose o LX6w
* Open. You can then make changes to the template in the Source Editor. ` M4;aN
*/ u
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package com.tot.count; 43:~kCF[s
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/** Um15@p;
* vn0XXuquzC
* @author yQ+#Tlji
*/ =q[3/'2V$?
public class CountBean { :n'QNGj
private String countType; ,)GCg@7B
int countId; $z@e19g T
/** Creates a new instance of CountData */ Ks
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public CountBean() {} j@kBCzX
public void setCountType(String countTypes){ &r DOqj
this.countType=countTypes; 66)@4 3V
} TmX~vZ
public void setCountId(int countIds){ ,[Cl 'B
this.countId=countIds; [b;Oalw
} }tv-
public String getCountType(){ gMI%z2]'-
return countType; *TE6p
} 7GK| A{r
public int getCountId(){ LUo3y'
return countId; ! h&hPY1
} _vU,avw
} ,=o q)Fm]
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CountCache.java 5/P?@`/eT
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/* 30<dEoF
* CountCache.java "-<u.$fE
* o{UwUMw5`
* Created on 2007年1月1日, 下午5:01 3O#7OL68v
* [mWo&Ph[-
* To change this template, choose Tools | Options and locate the template under >454Yir0Mk
* the Source Creation and Management node. Right-click the template and choose T| 4c\
* Open. You can then make changes to the template in the Source Editor. L?9Vz&8]
*/ <hy>NM@$
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package com.tot.count; X[Y!=e4z
import java.util.*; 4eaC18?
/** 4f"be
* 7qW:^2y
* @author Ubn5tN
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*/ i7fpl
public class CountCache { b> 2u>4
public static LinkedList list=new LinkedList(); y-sQ"HPN
/** Creates a new instance of CountCache */ yuI5#
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public CountCache() {} E/s3@-/
public static void add(CountBean cb){ sUbZVPDr
if(cb!=null){ RE"}+D
list.add(cb); te:"1:e
} D;d;:WT5
} 5YC(gv3/
} $yCj80m\
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CountControl.java `/+7@~[RU
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/* 4,<~t>M1
* CountThread.java ^@[[,1"K
* 2EK\QW o
* Created on 2007年1月1日, 下午4:57 P9%9/ B:-
* ]"CAP%
* To change this template, choose Tools | Options and locate the template under mDV 2vg
* the Source Creation and Management node. Right-click the template and choose ^Gd<miw
* Open. You can then make changes to the template in the Source Editor. 9w0 ^=
*/ 4-3B"
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package com.tot.count; uN`ACc)ESi
import tot.db.DBUtils; *VRFs=
import java.sql.*; ~s5Sk#.z5
/** DK)qBxc8
* cJ[n<hTv
* @author x!YfZ*
*/ qHHWe<}OT
public class CountControl{ 7B&nV92S
private static long lastExecuteTime=0;//上次更新时间 Ip2JzE
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 +pe_s&
/** Creates a new instance of CountThread */ R [uo:.
public CountControl() {} ~Kb(`Px@
public synchronized void executeUpdate(){ xc*ys-Nv
Connection conn=null; s#qq%
@
PreparedStatement ps=null; Vq<|DM3z<
try{ 0q`'65 lx
conn = DBUtils.getConnection(); 2RE }l=h5
conn.setAutoCommit(false); BAKfs/N
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); qx!IlO
for(int i=0;i<CountCache.list.size();i++){ WHpbQQX
CountBean cb=(CountBean)CountCache.list.getFirst(); #K)HuT
CountCache.list.removeFirst(); +[F9Q,bH@b
ps.setInt(1, cb.getCountId()); Hpsg[d)!
ps.executeUpdate();⑴ ;TW@{re
//ps.addBatch();⑵ "+XO[WGc
} +ubO-A?
//int [] counts = ps.executeBatch();⑶ 2G'G45Q
conn.commit(); +>:X4A*
}catch(Exception e){ MPGQ4v i&
e.printStackTrace(); 7rr5$,Mv
} finally{ uox;PDK
try{ Y0eu^p)
if(ps!=null) { }'X}!_9w>
ps.clearParameters(); c|O5Vp}
ps.close(); 3}T&|@*
ps=null; -nd6hx
} #Ta@A~.L
}catch(SQLException e){} d+^4;Hv4
DBUtils.closeConnection(conn); JTs.NY
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} fi,=z
} {u5)zVYC,U
public long getLast(){ 49kY]z|"w
return lastExecuteTime; yNN2}\[.
} gXfAz,
public void run(){ `o*eL Lk
long now = System.currentTimeMillis(); A!^,QRkRN
if ((now - lastExecuteTime) > executeSep) { YInW)My.h
//System.out.print("lastExecuteTime:"+lastExecuteTime); g@EKJFjl
//System.out.print(" now:"+now+"\n"); z&t6,0q`5
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); -u9{R \S
lastExecuteTime=now; @\q~OyV
executeUpdate(); <]!IC]+
} 8vP d~te
else{ U>I#f
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9B%"7MVn
} ipyO&v
} #pVk%5N
} |6;.C1\,
//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 Q;^([39DI
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类写好了,下面是在JSP中如下调用。 hZJ Nh,,w
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<% <w:fR|O
CountBean cb=new CountBean(); C<7J5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ! TRiFD
CountCache.add(cb); %-SP
out.print(CountCache.list.size()+"<br>"); 97&6i TYA
CountControl c=new CountControl(); |LjCtm)@+
c.run(); ca`=dwe>
out.print(CountCache.list.size()+"<br>"); kO9yei
%>