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: TB%NHq-!
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CountBean.java }v`Z.?|Z
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/* wZs jbNf`K
* CountData.java IQ $/|b/
* *v:o`{vM[
* Created on 2007年1月1日, 下午4:44 T!2gOe
* b(Nxk2uv
* To change this template, choose Tools | Options and locate the template under peZ'sZ 6
* the Source Creation and Management node. Right-click the template and choose *G"}m/j-
* Open. You can then make changes to the template in the Source Editor. NcyE_T
*/ n.b_fkZNr
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package com.tot.count; zLSha\X
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/** m5%E1k$=
* TNF+yj-|X:
* @author ,R7RXpP7t
*/ l,k.Jo5
public class CountBean { wu;^fL
private String countType; M!b-;{;'
int countId; 87-z=>IU
/** Creates a new instance of CountData */ l3Wh&*0
public CountBean() {} *s%M!YM
public void setCountType(String countTypes){ HXP/2&|JY
this.countType=countTypes; u):Nq<X
} FfM,~s<Efz
public void setCountId(int countIds){ v@1f,d
this.countId=countIds; {wptOZ
} BMH?BRi
public String getCountType(){ U1=]iG<%
return countType; Ol)M0u
} Fvr$K*u
public int getCountId(){ S^7u`-
return countId; 303x|y
} wqF_hs(O
} ~0YRWM ;
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CountCache.java 'EO"0,
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/*
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* CountCache.java l:14uWu|
* eEX* \1Gg
* Created on 2007年1月1日, 下午5:01 D"<>!]@(a
* @0D
* To change this template, choose Tools | Options and locate the template under s(r1q$5
* the Source Creation and Management node. Right-click the template and choose n*m"yp
* Open. You can then make changes to the template in the Source Editor. i{}Q5iy
*/ T1A/>\Ns
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package com.tot.count; Io4Ss1="
import java.util.*; Y.#:l<
/** Z"d21D~h9`
* a/gr1
* @author ,F?O} ijk
*/ X8 x:/]/0
public class CountCache { E.4 X,
public static LinkedList list=new LinkedList(); (BZd%!
/** Creates a new instance of CountCache */ 4Ep6vm X
public CountCache() {} t/c)[l hV
public static void add(CountBean cb){ xP5Z -eL
if(cb!=null){ n7,LfO#
list.add(cb); '&F
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} !4}Wp.
} HEs .pET\
} #OsUF,NU
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CountControl.java g]PC6xr38
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/* [w}KjV/yi
* CountThread.java s>a(#6Q
* t}2M8ue(&
* Created on 2007年1月1日, 下午4:57 r~; TId} #
* DC,]FmWs!+
* To change this template, choose Tools | Options and locate the template under uE&2M>2
* the Source Creation and Management node. Right-click the template and choose F>"B7:P1:Q
* Open. You can then make changes to the template in the Source Editor. O/lu0acI
*/ o(Q='kK
*/ok]kX'
package com.tot.count; 43/!pW
import tot.db.DBUtils; BF(Kaf;<t.
import java.sql.*; SAUG+{Uq
/** dk@iAL*v
* Rqun}v}
* @author s AlOX`t
*/ [OwrIL
public class CountControl{ f4+}k GJN
private static long lastExecuteTime=0;//上次更新时间 zF_aJ+i:~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 86ml.VOR
/** Creates a new instance of CountThread */ )"&\S6*!
public CountControl() {} .!Q?TSQ+{!
public synchronized void executeUpdate(){ 4/QQX;w
Connection conn=null; Kc{~Q
PreparedStatement ps=null; 4 moVS1
try{ c\N-B,m&
conn = DBUtils.getConnection(); fR,7l9<%Zp
conn.setAutoCommit(false); V6tUijz
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G-G\l?R(
for(int i=0;i<CountCache.list.size();i++){ Wfj*)j
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CountBean cb=(CountBean)CountCache.list.getFirst(); 3R[,,WAj$
CountCache.list.removeFirst(); (d}z>?L
ps.setInt(1, cb.getCountId()); Q) Y&h'.(
ps.executeUpdate();⑴ <j^"=UN4#
//ps.addBatch();⑵ @EGUQ|WL^
} LO;Z3Q>#0
//int [] counts = ps.executeBatch();⑶ RLUH[[
conn.commit(); ~n9-
}catch(Exception e){ 1"
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e.printStackTrace(); Y%YPR=j~ &
} finally{ |3uE"\nfA
try{ o,DI7sb
if(ps!=null) { Yc~c(1VRz
ps.clearParameters();
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ps.close(); U?yKwH^{
ps=null; %|gj46
} |p
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}catch(SQLException e){} m;m4/z3U
DBUtils.closeConnection(conn); o3xfif
} KI8Q
=*
} qh~S)^zFJ
public long getLast(){ rR3(yy0L
return lastExecuteTime; z9P;HGuZ
} 7Hp~:i30
public void run(){ ,?>:Cdz4
long now = System.currentTimeMillis(); te8lF{R
if ((now - lastExecuteTime) > executeSep) { ]x`I@vSf7R
//System.out.print("lastExecuteTime:"+lastExecuteTime); m~l[Y
//System.out.print(" now:"+now+"\n"); y3)R:h4AH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e!|T Tap
lastExecuteTime=now; 6>;dJV
executeUpdate(); cT,5xp"a
} '3V?M;3|K
else{ o _DZ
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ]2'{W]m
} 'X1fb:8m8
} `B7 1 `
} h?2 :'Vu]
//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 OA\
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类写好了,下面是在JSP中如下调用。 o&vODs
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<% Z|dng6ck
CountBean cb=new CountBean(); 4.0JgX
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o 2sOf
CountCache.add(cb); Q.]RYv}\
out.print(CountCache.list.size()+"<br>"); ziBg'
CountControl c=new CountControl(); L?p,Sy<RI
c.run(); d!]fou
out.print(CountCache.list.size()+"<br>"); V;t8v\
%>