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: R)=<q]Ms
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CountBean.java I(.XK ucU
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/* H;6V
* CountData.java o>YRKb
* 2-4%h!
* Created on 2007年1月1日, 下午4:44 oaHBz_pg
* ~EBZlTN
* To change this template, choose Tools | Options and locate the template under *K;~V
* the Source Creation and Management node. Right-click the template and choose 2+.m44>Ti
* Open. You can then make changes to the template in the Source Editor. !v-(O"a
*/ #?9oA4Q
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package com.tot.count; '&Ku Ba
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/** ?6Gq &
* 5>HI/QG
* @author PJLA^e C7>
*/ Dz?F,g_
public class CountBean { _?ym,@}#
private String countType; Z+?j8(:n
int countId; MAXdgL[]
/** Creates a new instance of CountData */ Z8 x(_ft5
public CountBean() {} G9
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public void setCountType(String countTypes){ }7V/(K
this.countType=countTypes; z)26Ahm TV
} sYz:(hZS
public void setCountId(int countIds){ xASjw?
this.countId=countIds; xiI!_0'
} y!#1A?|k
public String getCountType(){ Umqm5*P(
return countType; #ua#$&p
} (n<xoV[e
public int getCountId(){ 46vz=# ,6L
return countId; 0ode&dB
} UX?_IgJh<"
} 0V^?~ex
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CountCache.java B 5?(gb"
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/* &"BKue~q@p
* CountCache.java ,FTF@h-Cs
* */1z=
* Created on 2007年1月1日, 下午5:01 |^1eL I
* jkbz8.K
* To change this template, choose Tools | Options and locate the template under 6jn<YR
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* the Source Creation and Management node. Right-click the template and choose 4avM:h
* Open. You can then make changes to the template in the Source Editor. j_}e%,}
*/ dCHU* 7DS
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package com.tot.count; NYCkYI
import java.util.*; SbB5J> >7J
/** cIgF]My*D@
* 1G\ugLm
* @author ~"-wSAm
*/ !} 1p:@
public class CountCache { qRU8uu
public static LinkedList list=new LinkedList(); = *sP,
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/** Creates a new instance of CountCache */ ?0.+DB
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public CountCache() {} `);`E_'U
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public static void add(CountBean cb){ xkX,
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if(cb!=null){ htjJ0>&
list.add(cb); (]ORB0kl
} eq"~by[Uq
} {PfE7KH
} @g{=f55
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CountControl.java C}Khh`8@5.
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/* a`T{5*@
* CountThread.java 0q/g:"|j
* }p#S;JZRu+
* Created on 2007年1月1日, 下午4:57 Hi?],5,/
* AVi|JY)>
* To change this template, choose Tools | Options and locate the template under cD{[rI
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* the Source Creation and Management node. Right-click the template and choose a9"Gg}h\
* Open. You can then make changes to the template in the Source Editor. ]Z~H9!%t
*/ Y A;S'dxY
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package com.tot.count; c<e$6:|xM
import tot.db.DBUtils; y"7?]#$9/
import java.sql.*; SO}Hc;Q1`
/** +%FGti$[
* lVqvS/_k$
* @author kJ~^
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*/ )q#b^( v
public class CountControl{ %1#5
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private static long lastExecuteTime=0;//上次更新时间 W
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 2LgRgY{Bl
/** Creates a new instance of CountThread */ ~oOOCB
public CountControl() {} yXDf;`J
public synchronized void executeUpdate(){ 2lGq6Au:
Connection conn=null; r:u5+A
PreparedStatement ps=null; JK_sl>v.7
try{ zRB1V99k
conn = DBUtils.getConnection(); Q<"zpwHR
conn.setAutoCommit(false); f$P pFSY4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); wZ*m
for(int i=0;i<CountCache.list.size();i++){ N^)L@6
CountBean cb=(CountBean)CountCache.list.getFirst(); r|&qXb x
CountCache.list.removeFirst(); ><$hFrR!
ps.setInt(1, cb.getCountId()); ;VvqKyUh7`
ps.executeUpdate();⑴ gllXJM^ -
//ps.addBatch();⑵ -PxA~((g5
} E9|i:
//int [] counts = ps.executeBatch();⑶ h8n J$jg
conn.commit(); ?+51 B-
}catch(Exception e){ L!5%;!>.P
e.printStackTrace(); n2$*Z6.G
} finally{ *F&C`]
try{ aG,N>0k8
if(ps!=null) { NK d8XQ=%
ps.clearParameters(); #A?U_32z/2
ps.close(); a?@j`@]ZR~
ps=null; @v |_APy#
} O"Ar3>
}catch(SQLException e){} [_${N,1
DBUtils.closeConnection(conn); r]2}S=[
}
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} TC ^EyjD
public long getLast(){ qdOaibH_
return lastExecuteTime; P E.^!j
} .4U::j}
public void run(){ #VD[\#
long now = System.currentTimeMillis(); DUa`8cE}
if ((now - lastExecuteTime) > executeSep) { 2TY|)ltsF
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]_j{b)t
//System.out.print(" now:"+now+"\n"); j5tA!o
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 5&6S["lt
lastExecuteTime=now; l 4(-yWC$H
executeUpdate(); #Ey!?Z
} 7j{SCE;
else{ Dk8"
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); .|cQ0:B[
} 7+@:wX\
} l9# v r
} ~^Gk7
//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 @TsOc0?-
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类写好了,下面是在JSP中如下调用。 *YYm;J'
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<% Pr/K5aJeg
CountBean cb=new CountBean(); p ^T0(\1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $--W,ov5j
CountCache.add(cb); Hb IRE
out.print(CountCache.list.size()+"<br>"); K6_{AuL}4
CountControl c=new CountControl(); %J7 ;b<}To
c.run(); H7*/
out.print(CountCache.list.size()+"<br>"); a+IU<O-J?
%>