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: 8[LwG&
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CountBean.java "Y@rNmBj
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/* ")|3ZB7>*
* CountData.java m7X&"0X
* j:D@X=|
* Created on 2007年1月1日, 下午4:44 QC.WR'.
* p2}$S@GD
* To change this template, choose Tools | Options and locate the template under <,qJ%kc
* the Source Creation and Management node. Right-click the template and choose ,2mnjq/*Z
* Open. You can then make changes to the template in the Source Editor. P;[5#-e
*/ Gv[W)+3f
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package com.tot.count; @AUx%:}0Y:
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/** (g,lDU[=
* ^,zE Nqg7
* @author qq}EXq ^
*/ {<~0nLyJS
public class CountBean { vlCjh! x
private String countType; oXwoi!
int countId; KNU/Kc#
/** Creates a new instance of CountData */ vTN/ho,H
public CountBean() {} $|.x !sA
public void setCountType(String countTypes){ 7"F
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this.countType=countTypes; .{D[!Dp#h
} AfKJaDKf
public void setCountId(int countIds){ 0gPz|v>z
this.countId=countIds; jI@0jxF
} r{qM!(T
public String getCountType(){ FRI<A8
return countType; \7Hzj0hSi
} 5;{d*L
public int getCountId(){ :)}iWKAse
return countId; "!<Kmh5
} 6'W79
} j &)Xi^^
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CountCache.java b)@%gS\F
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/* _F
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* CountCache.java DG8]FhD^b
* jEfrxlj
* Created on 2007年1月1日, 下午5:01 .!0),KmkK
* iRo UM.%
* To change this template, choose Tools | Options and locate the template under F7J-@T<
* the Source Creation and Management node. Right-click the template and choose 8'J>@ uW
* Open. You can then make changes to the template in the Source Editor. jPYed@[+
*/ V1Dwh@iS
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package com.tot.count; .$)'7
import java.util.*; ju8tNL,J
/** QQPbKok>
* {55{YDqx
* @author @PuJre4!;L
*/ CF9a~^+%
public class CountCache { o%h"gbvMY!
public static LinkedList list=new LinkedList(); qC?J`
/** Creates a new instance of CountCache */ u7G@VZ Ux5
public CountCache() {} t
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public static void add(CountBean cb){ Z_F:H@-&
if(cb!=null){ O_0|Q@
list.add(cb); S$\lM<M
} CyO2Z
} /,$;xt-J35
} m8$6FN
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CountControl.java Je2o('MA
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/* is?`tre\P
* CountThread.java 85Q2c
* rxC EOG
* Created on 2007年1月1日, 下午4:57 jV8mn{<
* +`9
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* To change this template, choose Tools | Options and locate the template under JV(eHuw
* the Source Creation and Management node. Right-click the template and choose g 'c4&Do
* Open. You can then make changes to the template in the Source Editor. k(<5tv d
*/ HxAq& J;xu
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package com.tot.count; PXm{GLXRS;
import tot.db.DBUtils; ZT4._|2
import java.sql.*; AuHOdiJ
/** "o#"u[W,
* Ya*lq!
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* @author lxj_(Uo
*/ G U~?S'{
public class CountControl{ @!fy24R]D
private static long lastExecuteTime=0;//上次更新时间 WGKN>nV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ][S<M24]Q
/** Creates a new instance of CountThread */ |vz<FR6
public CountControl() {} _IOeO
public synchronized void executeUpdate(){ l"o@.C}f/
Connection conn=null; QKc3Q5)@j
PreparedStatement ps=null; 6=A2Y:8
try{ X'.}#R1
conn = DBUtils.getConnection(); !1+L0,I6
conn.setAutoCommit(false); \$^ z.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); \lCr~D5
for(int i=0;i<CountCache.list.size();i++){ 5 g99t$p9
CountBean cb=(CountBean)CountCache.list.getFirst(); UoPd>q4Uj
CountCache.list.removeFirst(); l>h%J,W
ps.setInt(1, cb.getCountId()); ~6.AE/ow
ps.executeUpdate();⑴ fF[n?:VV
//ps.addBatch();⑵ En8-Hc#NC
} qqT6C%Q`kG
//int [] counts = ps.executeBatch();⑶ Jx1oK
conn.commit(); 6[wej$u
}catch(Exception e){ ~[Mk QJxe
e.printStackTrace(); P~redX=t@
} finally{ kU_bLC?>D
try{ \2-!%i,
if(ps!=null) { kLMg|48fdI
ps.clearParameters(); a1M-F3
ps.close(); yk!,{Q?<$
ps=null; !vfjo[v
} ps"crV-W
}catch(SQLException e){} uljd)kLy4O
DBUtils.closeConnection(conn); Gv>,Ad
ka
} dr^pzM!N
} dm,7OQ
public long getLast(){ | ctGxS9
return lastExecuteTime; d~C
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} f3lFpS
public void run(){ ?'CIt5n+\{
long now = System.currentTimeMillis(); [%YA42_`LD
if ((now - lastExecuteTime) > executeSep) { T9KzVxHp5
//System.out.print("lastExecuteTime:"+lastExecuteTime); ?;,s=2
//System.out.print(" now:"+now+"\n"); @YdS_W
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); .a:"B\B`
lastExecuteTime=now; \E9Z
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executeUpdate(); oc?,8I[P5
} yU\&\fD>j
else{ Nz#T)MGO`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P.3j |)NW
} Im{50%Y
} Vi23pDZ5
} V;L^q?v
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//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 ~IZ'zuc
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类写好了,下面是在JSP中如下调用。 dc5w_98o
{#:js
<% IKKd
CountBean cb=new CountBean(); L-^vlP)Vu
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); R3d>|`) +
CountCache.add(cb); yX$I<L<Suz
out.print(CountCache.list.size()+"<br>"); %CfJ.;BDNE
CountControl c=new CountControl(); { >{|3
c.run(); AW&HWc~A
out.print(CountCache.list.size()+"<br>"); I7 pxi$8f
%>