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: ]0le=Ee^%
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CountBean.java OHo0W)XUU
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/* ]Ox.6BKjDP
* CountData.java 8<xy*=%
* Z}wAh|N-
* Created on 2007年1月1日, 下午4:44 !
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* "/"k50%
* To change this template, choose Tools | Options and locate the template under O7sn>uO
* the Source Creation and Management node. Right-click the template and choose m}(DJ?qP
* Open. You can then make changes to the template in the Source Editor. /'(P{O>{j
*/ V2.K*CpZ7
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package com.tot.count; M~IiJ9{
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/** {Hv=iVmt
* #a&Vx&7L
* @author {65X37W
*/ $j/F7.S
public class CountBean { j;
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private String countType; [% jg;m
int countId; 2,\uY}4
/** Creates a new instance of CountData */ [~3p+
public CountBean() {} k<qQ+\X
public void setCountType(String countTypes){ WJ*DWyd''
this.countType=countTypes; F\e'z
} u@HP@>V
public void setCountId(int countIds){ O\w%E@9Fh
this.countId=countIds; bCF63(0
} -1R~3j1_
public String getCountType(){ ?r+tU
return countType; cg~FW2Q
} b<8h\fR#'
public int getCountId(){ +uA<g`4
return countId; b}
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} 'e)t+
} ?9mY #_Of
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CountCache.java Rl~Tw9
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/* TaC)N
* CountCache.java Uu(W62
* ?|33Np)
* Created on 2007年1月1日, 下午5:01 BK{8\/dg
* J L3A/^
* To change this template, choose Tools | Options and locate the template under (F)zj<{f
* the Source Creation and Management node. Right-click the template and choose mf3 G$=[
* Open. You can then make changes to the template in the Source Editor. 2'_sGAH
*/ "hvw2lyp3
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package com.tot.count; k"Is.[I?^
import java.util.*; 86_Zh5:
/** EW`3h9v~
* 1/n3qJyx2}
* @author rLnu\X=h$
*/ q=bXHtU
public class CountCache { q\,H9/.0k
public static LinkedList list=new LinkedList(); ,wV2ZEW}e
/** Creates a new instance of CountCache */ Ort\J~O
public CountCache() {} Gc'HF"w
public static void add(CountBean cb){ *M*k-Z':.*
if(cb!=null){ j@DyWm/7
list.add(cb); hYV{N7$U|
} pv T!6+
} z23KSPo
} iqU}t2vFrj
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CountControl.java +bXZE
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/* 6/z}-;,W'
* CountThread.java gO5;hd[l
* L?P8/]DGp
* Created on 2007年1月1日, 下午4:57 .D) }MyKnu
* t@ Jo ?0s
* To change this template, choose Tools | Options and locate the template under *~vRbD$q
* the Source Creation and Management node. Right-click the template and choose 0Zq"-
* Open. You can then make changes to the template in the Source Editor. UJZa1p@L
*/ _CZ* z
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package com.tot.count; L}9@kjW
import tot.db.DBUtils; ^;2L`U@5
import java.sql.*; ]}B&-Yp
/** j7W_%Yk|E
* /L~*FQQK>
* @author pZR^ HOq
*/ |QY+vO7fxj
public class CountControl{ w &-r
private static long lastExecuteTime=0;//上次更新时间 7HF\)cz2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 lz( 9pz
/** Creates a new instance of CountThread */ :eO]65N
public CountControl() {} U` U/|@6
public synchronized void executeUpdate(){ & #|vGhA
Connection conn=null; k >MgrtJI
PreparedStatement ps=null; )uaB^L1
try{ Bm?Ku7}.
conn = DBUtils.getConnection(); T>z@;5C
conn.setAutoCommit(false); v`fUAm/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); :Cuae?O,
for(int i=0;i<CountCache.list.size();i++){ J
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CountBean cb=(CountBean)CountCache.list.getFirst(); A(uN=r@O
CountCache.list.removeFirst(); qq/Cn4fN8
ps.setInt(1, cb.getCountId()); Vg3&:g5 /
ps.executeUpdate();⑴ #4hP_Vhc
//ps.addBatch();⑵ $~-j-0
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} Qw^tzP8
//int [] counts = ps.executeBatch();⑶ I2 Kb.`'!
conn.commit(); {> }U>V
}catch(Exception e){ ZO`d
e.printStackTrace(); P-mrH
} finally{ m&\Gz*)3
try{ T;% SB&
if(ps!=null) { k"U4E
J{
ps.clearParameters(); #Z.JOwi
ps.close(); $DVy$)a!u
ps=null; tY#^3ac
} 9+/|sU\.%
}catch(SQLException e){} N.<hZ\].=
DBUtils.closeConnection(conn); #=tWCxf=
} NanU%#&
} +!<`$+W
public long getLast(){ "gO5dZ\0
return lastExecuteTime; =Dz[|$dV
} NX;&V7
public void run(){ V]AL'}(
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long now = System.currentTimeMillis(); bc ZonS
if ((now - lastExecuteTime) > executeSep) { jQDxbkIuzE
//System.out.print("lastExecuteTime:"+lastExecuteTime); -K!-a'J
//System.out.print(" now:"+now+"\n"); 3k/MigT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); HfF$>Z'kM
lastExecuteTime=now; |(V3
executeUpdate(); D%A-& =
} +~@Y#>+./l
else{ 26**tB<
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9p.>L8
} u|ZO"t
} h(L5MZs
} Px8E~X<@
//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 4Y2>w
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类写好了,下面是在JSP中如下调用。 (07d0 <<[
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<% 2S;zze7)
CountBean cb=new CountBean(); ?Y9?x,x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); [>0r'-kI
CountCache.add(cb); SS`C0&I@p
out.print(CountCache.list.size()+"<br>"); YV
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CountControl c=new CountControl(); $d"+Njd
c.run(); .>YJ95&\
out.print(CountCache.list.size()+"<br>"); NO$Nl/XM
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