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: blahi]{Y9
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CountBean.java _6MdF<Xb/
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/* ka/XK[/'
* CountData.java 02\JzBU
* Gr: 3{o`
* Created on 2007年1月1日, 下午4:44 !8R@@,_v
* #? ?%B
* To change this template, choose Tools | Options and locate the template under aXY-><
* the Source Creation and Management node. Right-click the template and choose 88lxHoPV
* Open. You can then make changes to the template in the Source Editor. }gGkV]
*/ A\AT0th
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package com.tot.count; pB p#a
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/** k6(r !mc
* h2w}wsb0l
* @author |c2xy
*/ <G~>~L.E
public class CountBean { T6M+|"92
private String countType; S1J<9xqSQ8
int countId; 347eis'
/** Creates a new instance of CountData */ Quzo8u
public CountBean() {} p $ouh
public void setCountType(String countTypes){ QTmZ(>z
this.countType=countTypes; ,=BLnsg
} .Cz %:%9
public void setCountId(int countIds){ <
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this.countId=countIds; 2p!"p`b~
} xHo&[{
public String getCountType(){ Pc_VY>Ty
return countType; JObMZA$
} 2c(aO[%h9
public int getCountId(){ vq!uD!lr
return countId; 7dOyxr"H-
} zt=0o|k
} z42F,4Gk
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CountCache.java /6+NU^
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/* Uxu\u0*
* CountCache.java E9}{1A
* ymN!-x8q>'
* Created on 2007年1月1日, 下午5:01 yx>_scv,T
* ?okx<'"[
* To change this template, choose Tools | Options and locate the template under jS<_ )
* the Source Creation and Management node. Right-click the template and choose tPfFqqT
* Open. You can then make changes to the template in the Source Editor. ]zfG~^.
*/ 7~1IO|4t
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package com.tot.count; e]Fp=*#
import java.util.*; Sr_VL:Gg
/** Ysi
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* -JT/9IQ
* @author %rkk>m
*/ `ln1$
public class CountCache { %Ym^{N
public static LinkedList list=new LinkedList(); '%saL >0
/** Creates a new instance of CountCache */ fc_2D|
public CountCache() {} z=7|{ G
public static void add(CountBean cb){ 51BlM%
if(cb!=null){ H1EDMhn/
list.add(cb); "v-(g9(
} G?c-79]U
} GV.A+u
} %9v@0}5V
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CountControl.java #z'uRHx%=0
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/* 6Jz^
* CountThread.java 9uk<&nqx
* \]4v_!
* Created on 2007年1月1日, 下午4:57 ~b~2
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* *^%*o?M~
* To change this template, choose Tools | Options and locate the template under zj{r^D$
* the Source Creation and Management node. Right-click the template and choose K(}AX+rIg
* Open. You can then make changes to the template in the Source Editor. MrRaU x6z
*/ dt}_D={Be
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package com.tot.count; M]]pTU((
import tot.db.DBUtils; #/2$+x
import java.sql.*; 4qi[r)G
/** [K/m
* ;)AfB#:d
* @author 0\9K3
*/ 5ExDB6Bx@y
public class CountControl{ PxFWJ?=
private static long lastExecuteTime=0;//上次更新时间 ~]C%/gEh
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 x#.C4O09
/** Creates a new instance of CountThread */ p>v U?eF
public CountControl() {} mTNB88p8^D
public synchronized void executeUpdate(){ RDqFL.-S
Connection conn=null; .
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PreparedStatement ps=null; :Y,BdU
try{ 1BHG'y
conn = DBUtils.getConnection(); y
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conn.setAutoCommit(false); VZ&
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }Z-Z|G)#
for(int i=0;i<CountCache.list.size();i++){ <
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CountBean cb=(CountBean)CountCache.list.getFirst(); $Fkaa<9;P
CountCache.list.removeFirst(); J(4"S o_
ps.setInt(1, cb.getCountId()); d?AlI
ps.executeUpdate();⑴ 5q9s,r_
//ps.addBatch();⑵ rKH:[lKm
} ew _-Eb
//int [] counts = ps.executeBatch();⑶ ?<Wb@6kh`
conn.commit(); w;UqEC V
}catch(Exception e){ u9+kLepOT
e.printStackTrace(); uDw.|B2ui
} finally{ FGWN}&K
try{ 94skkEj
if(ps!=null) { CIU1R;
ps.clearParameters(); \s"U{N-
ps.close(); 4(6b(]G'#
ps=null; PO:"B6
} W14F
}catch(SQLException e){} 2d%}- nw
DBUtils.closeConnection(conn); ZF7IL
}
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} ez]tAW
public long getLast(){ <JMcIV837
return lastExecuteTime; bV8g|l-4(
} css64WX^0c
public void run(){ g V5zSudW
long now = System.currentTimeMillis(); D8&`R
if ((now - lastExecuteTime) > executeSep) { ,Ys"W x
//System.out.print("lastExecuteTime:"+lastExecuteTime); -=s(l.?Hm5
//System.out.print(" now:"+now+"\n"); O,aS`u &
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); tCxF~L@
lastExecuteTime=now; Z6\+
executeUpdate(); m,C1J%{^
} lif&@of
else{ FR2=
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); WE]e
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} BH]Yn u&o
} akw,P$i
} 3rLTF\
//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 `w I /0
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类写好了,下面是在JSP中如下调用。 )i+2X5B`S
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<% !EUan
CountBean cb=new CountBean(); gs!(;N\j|
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); w 4[{2
CountCache.add(cb); !*- >;:9B
out.print(CountCache.list.size()+"<br>"); "ju6XdZo
CountControl c=new CountControl();
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c.run(); AJ#Nenmj
out.print(CountCache.list.size()+"<br>"); D}8EER b
%>