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: B Z|A&;
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CountBean.java ,#UZp\zZ*
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/* 4[@YF@_=M
* CountData.java ] re=8s6
* E#!!tH`lgg
* Created on 2007年1月1日, 下午4:44 _ Lb"yug
* gr*CN<
* To change this template, choose Tools | Options and locate the template under ;5bd<N
* the Source Creation and Management node. Right-click the template and choose v8*)^-Fx
* Open. You can then make changes to the template in the Source Editor. oD V6[e
*/ ;o3gR4u_L
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package com.tot.count; c%C6d97q
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/** RC/ 3\'
* 4_kN';a4Q
* @author tLWw<)t
*/ N=BG0t$
public class CountBean { (_zlCHB
private String countType; *$ g!/,
int countId;
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/** Creates a new instance of CountData */ GeTk/tU
public CountBean() {} ,< x/
public void setCountType(String countTypes){ ]~I+d/k
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this.countType=countTypes; X n$ZA-
} R,G*]/r`
public void setCountId(int countIds){ 9Q%lS
this.countId=countIds; s:}? rSI
} x{SlJ%V
public String getCountType(){ T:$^1"\
return countType; WJOoDS!i
} +Cw_qS"=
public int getCountId(){ ~2"hh$
return countId; h<U?WtWT-p
} R~4X?@ZB
} Q!;syJBb.
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CountCache.java xKG7d8=
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/* ^obuMQ;
* CountCache.java 9p qsr~
* V_gl#e#
* Created on 2007年1月1日, 下午5:01 b<00 %Z
* `y3'v]
* To change this template, choose Tools | Options and locate the template under :J`@@H
* the Source Creation and Management node. Right-click the template and choose Wr%ov6:
* Open. You can then make changes to the template in the Source Editor. E7fQ9]
*/ I_<XL<
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package com.tot.count; MqnUym
import java.util.*; 0I)$!1~O)
/** G kjfDY:
* 2+gbMd4n
* @author 8|i'~BFHs
*/ 4w^o !
public class CountCache { $+'H000x
public static LinkedList list=new LinkedList(); T+v*@#iJ_
/** Creates a new instance of CountCache */ WFOJg&
public CountCache() {} x,,y}_YX
public static void add(CountBean cb){ Io]FDPN
if(cb!=null){ V.P<>~W
list.add(cb); TlS? S+
} ma~#E$i&
} \b"rf697,
} a/j;1xcc<
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CountControl.java {h?pvH_>
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/* L/"};VI
* CountThread.java [Cl0Kw.LD
* JpC'(N
* Created on 2007年1月1日, 下午4:57 :Z//
* H2s:M
* To change this template, choose Tools | Options and locate the template under _J
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* the Source Creation and Management node. Right-click the template and choose {Yj5Mj|#
* Open. You can then make changes to the template in the Source Editor. N `|A
*/ &:&89<C'
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package com.tot.count; `I5^zi8
import tot.db.DBUtils; =%X."i1A
import java.sql.*; ^3$l!>me
/** $N=&D_Q
* R |c=I}@F
* @author {cm?Q\DT
*/ _RbfyyaN
public class CountControl{ 6{y7e L3!
private static long lastExecuteTime=0;//上次更新时间 fCr2'+O"b
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 t1FtYXv`/
/** Creates a new instance of CountThread */ 1Z# $X`
public CountControl() {} gJ6`Kl985O
public synchronized void executeUpdate(){ @V%\Gspv
Connection conn=null; qT$k%(
PreparedStatement ps=null; c@t?R$c
try{ Ga7E}y%
conn = DBUtils.getConnection(); >|QH
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conn.setAutoCommit(false); |Kd#pYt%O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); f$o^Xu
for(int i=0;i<CountCache.list.size();i++){ 5*YoK)2J
CountBean cb=(CountBean)CountCache.list.getFirst(); |p6d]#z3
CountCache.list.removeFirst(); aOzIo-
ps.setInt(1, cb.getCountId()); iS$[dC ?N
ps.executeUpdate();⑴ !=dz^f.{
//ps.addBatch();⑵ G?W:O{n3
} >v:ex(y0
//int [] counts = ps.executeBatch();⑶ ra$:ibLN
conn.commit(); FU3K?A
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}catch(Exception e){ .k,j64
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e.printStackTrace(); (C!p2f
} finally{ V?u#WJy/
try{ aA`eKy) \
if(ps!=null) { J2=4%#R!
ps.clearParameters(); $Ll9ak}
ps.close(); GcVQz[E
ps=null; ]8p{A#1
} b>07t!;
}catch(SQLException e){} v"G1vSx)BT
DBUtils.closeConnection(conn); y]j.PT`Cw
} YN8x|DLi?
} 3V k8'
public long getLast(){ U]3!"+Y1P
return lastExecuteTime; hd)Jq'MCS
} 54_}9_g
public void run(){ }'oU/@yG
long now = System.currentTimeMillis(); Z.\q$U7'9
if ((now - lastExecuteTime) > executeSep) { ;I>nA6A
//System.out.print("lastExecuteTime:"+lastExecuteTime); cJ4My#w
//System.out.print(" now:"+now+"\n"); KL&/Yt
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2*NPK}
lastExecuteTime=now; Rt8[P6e"q
executeUpdate(); h*S"]ye5
} -n _Y.~
else{ S<nF>JRJa
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); tu
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} #1<m\z 7l
} J>Ar(p
} LDt6<D8,Q
//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 $plk>Khg
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类写好了,下面是在JSP中如下调用。 FuHBzBoM=
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<% >]h{[kU %4
CountBean cb=new CountBean(); >XgoN\w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); A!lZyG!3
CountCache.add(cb); C>Ik ;
out.print(CountCache.list.size()+"<br>"); 7hk)I`o65
CountControl c=new CountControl(); |bnd92fvks
c.run(); z$1RD)TQB
out.print(CountCache.list.size()+"<br>"); fbq$:Q44
%>