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: N&M~0iw
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CountBean.java LGl2$#x
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/* KjQR$-
* CountData.java 6qaulwV4t
* m'f,_ \'
* Created on 2007年1月1日, 下午4:44 d20gf:@BM
*
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* To change this template, choose Tools | Options and locate the template under X@f "-\
* the Source Creation and Management node. Right-click the template and choose A7n\h-b
* Open. You can then make changes to the template in the Source Editor. OD5m9XS
*/ SGe^ogO"v
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package com.tot.count; ^g`&7tX
[3!~PR]
/** y>aZXa
* IEzaK
* @author R[;zX(y
*/ -k"^o!p
public class CountBean { HTyLJe
private String countType; ^6_Cc
int countId; DuOG {
/** Creates a new instance of CountData */ !Uq^7Mw
public CountBean() {} ('hEr~&
public void setCountType(String countTypes){ xa
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this.countType=countTypes; YWxc-fPZ
} kJ Mf
public void setCountId(int countIds){ 1SR+m>pL
this.countId=countIds; u6bXv(
} aG92ay
public String getCountType(){ .Fa4shNV
return countType; <0PT"ij
} Gqy,u3lE
public int getCountId(){ 0JJS2oY/
return countId; I:d[Q
s
} uI DuGrt
} $.[#0lCI
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CountCache.java H[='~%D
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/* `2PLWo
* CountCache.java |H!9fZO
* *Otg*,\
* Created on 2007年1月1日, 下午5:01 ,Uy|5zv
* )uqA(R>
* To change this template, choose Tools | Options and locate the template under Co3:*nbRv
* the Source Creation and Management node. Right-click the template and choose h`H,a7
* Open. You can then make changes to the template in the Source Editor. -G|G_$9
*/ 3hK#'."`N
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package com.tot.count; v= N!SaK{
import java.util.*; @-&s: Qli
/** K/}rP[H
* "^1L'4'S
* @author kGN+rHo
*/ gL3"Gg3
public class CountCache { -k7X:!>QHC
public static LinkedList list=new LinkedList(); Q(\4]i< S
/** Creates a new instance of CountCache */ zrU{@z$l
public CountCache() {} yOwA8^q
public static void add(CountBean cb){ =lu/9
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if(cb!=null){ A2nqf^b{#
list.add(cb); zH*KYB
} H~E(JLcU
} vC5n[0
} EMc;^ d
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CountControl.java pm6>_Kz
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/* V14B[|YM<
* CountThread.java 0pSmj2/,.
* %/rMg"f:
* Created on 2007年1月1日, 下午4:57 6AWKLFMV
* np4+"
* To change this template, choose Tools | Options and locate the template under ''kS*3
* the Source Creation and Management node. Right-click the template and choose LbII?N8`N
* Open. You can then make changes to the template in the Source Editor. %G?;!Lz
*/ k}#;Uy=5
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package com.tot.count; w`DW(hXJ
import tot.db.DBUtils;
-!\fpl{
import java.sql.*; ez9q7SpA
/** #"49fMi/
* >[1W:KQA
* @author ?}B:
*/ oY=q4D
public class CountControl{ g(|6~}|o+
private static long lastExecuteTime=0;//上次更新时间 q}FVzahv
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 1c@}C+F+
/** Creates a new instance of CountThread */ L.=w?%:H=
public CountControl() {} Nlj^Dm
public synchronized void executeUpdate(){ | 0,vQv
Connection conn=null; o5n^!gi4
PreparedStatement ps=null; )=DGdIEt
try{ NOS>8sy
conn = DBUtils.getConnection(); &k8vWXMGk%
conn.setAutoCommit(false); BJS-Jy$-
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :ah
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for(int i=0;i<CountCache.list.size();i++){ {W\T"7H
CountBean cb=(CountBean)CountCache.list.getFirst(); @WKzX41'
CountCache.list.removeFirst(); ?J,AB #+
ps.setInt(1, cb.getCountId()); 28OWNS
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ps.executeUpdate();⑴ wIf
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//ps.addBatch();⑵ T,_(?YJW
} U'*t~x<
//int [] counts = ps.executeBatch();⑶ -ti{6:H8
conn.commit(); 5%}wV,Y
}catch(Exception e){ wl1m*`$
e.printStackTrace(); &J!aw
} finally{ pZZf[p^s|
try{ 1h7+@#<:a
if(ps!=null) { 5TUNX^AW
ps.clearParameters(); gip/(/NX
ps.close(); 9,]5v+
ps=null; Yif*"oO
} -]:GL>b
}catch(SQLException e){} fj ,m
DBUtils.closeConnection(conn); ai*b:Q
} O3o: qly!
} 2ij#
H
;
public long getLast(){ rNl.7O9b
return lastExecuteTime; oK9'
} T5O _LCIws
public void run(){ H@uE>
long now = System.currentTimeMillis(); OU7 %V)X5
if ((now - lastExecuteTime) > executeSep) { l?*r5[O>n
//System.out.print("lastExecuteTime:"+lastExecuteTime); _DP|-bp D
//System.out.print(" now:"+now+"\n"); GYB+RU}],
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _;RVe"tR#
lastExecuteTime=now; "gW7<ilw
executeUpdate(); N{d@^Yj
} DDd|T;8
else{ Bf4%G,o5
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); o0z67(N&g
} zX7q:Pt
} ~2_lp^Y
} qO`qJ/
//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 o{-<L
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类写好了,下面是在JSP中如下调用。 Cpx+qQt0
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<% ;9uRO*H?T
CountBean cb=new CountBean(); sNU}n<J-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); @\Js8[wS9@
CountCache.add(cb); UmK X*T9
out.print(CountCache.list.size()+"<br>"); hh.Q\qhubB
CountControl c=new CountControl(); ,7d|O}B
c.run(); 7]22"mc
out.print(CountCache.list.size()+"<br>"); ?q91:H
%>