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: UQg_y3
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CountBean.java 6l PuYEmT
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/* {4$aA*
* CountData.java DDq?4
* i-}Tt<^
* Created on 2007年1月1日, 下午4:44 TILH[r&Jg
* JvsL]yRT
* To change this template, choose Tools | Options and locate the template under }BUm}.-{u,
* the Source Creation and Management node. Right-click the template and choose RW<10:
* Open. You can then make changes to the template in the Source Editor. 4?fpk9c{2
*/ %g~&$oZmq
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package com.tot.count; z1^3~U$}
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/** >V>`}TIH
* =axuL P))
* @author t#VX#dJ
*/ 5WA:gy gB&
public class CountBean { /9A6"Z
private String countType; 1bFGoLAEFl
int countId; MH|F<$42
/** Creates a new instance of CountData */ !|l7b2NEz-
public CountBean() {} !' 0PM[
public void setCountType(String countTypes){ [C/{ ru&E
this.countType=countTypes; g t9(5p
} &Hyy .a
public void setCountId(int countIds){ qj/Zk[
this.countId=countIds; WH"'Ju5}
} {<$tEj:
public String getCountType(){ FUXJy{n6"2
return countType; 01&@8z'E
} 2acTw#
public int getCountId(){ L]%!YP\<T
return countId; 2rW9ja
} &Dt=[yqeG
} V!(7=ku!`
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CountCache.java }d>Xh8:%)
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/* lcLDCt?
* CountCache.java L/E7xLz
* E+ |K3EJ
* Created on 2007年1月1日, 下午5:01 DgK*>A
* ACy}w?D<
* To change this template, choose Tools | Options and locate the template under >9mj/P D
* the Source Creation and Management node. Right-click the template and choose ]imVIu
* Open. You can then make changes to the template in the Source Editor. (?g+.]Dt,
*/ 4x<H=CJC
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package com.tot.count; +V(^"Z~
import java.util.*; vS"h`pL
/** X- X`Z`o
* *p=enflU
* @author M7T*J>i
*/ MkHkM
public class CountCache { k<P`
public static LinkedList list=new LinkedList(); *~YdL7f)J
/** Creates a new instance of CountCache */ 6.a5%:
public CountCache() {} 6"+9$nFyW
public static void add(CountBean cb){ ?A3u2-
if(cb!=null){ $P#x>#+[A
list.add(cb); IN@o9pUjV
} >tPf.xI|l
} vQp'bRR
} YXZP-=fB>i
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CountControl.java "O-X*>?f
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/* .p.(
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* CountThread.java )hl7)~S<
* 10h;N[
* Created on 2007年1月1日, 下午4:57 z5oJQPPi
* \NMqlxp2
* To change this template, choose Tools | Options and locate the template under 0%<
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* the Source Creation and Management node. Right-click the template and choose t)Cf]]dV
* Open. You can then make changes to the template in the Source Editor. t#@z_Mn\
*/ x/CM)!U)
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package com.tot.count; 6Q\|8a
import tot.db.DBUtils; =4'V}p
import java.sql.*; MUsF
/** |OAM;@jH
* qjh k#\y
* @author Woj5
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*/ 0;@>jo6,!
public class CountControl{ `"[qb ?z
private static long lastExecuteTime=0;//上次更新时间 ,`RX~ H=C
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 n?$c"}
/** Creates a new instance of CountThread */ Ynvf;qs
public CountControl() {} u8.Tu7~
public synchronized void executeUpdate(){ .)$MZyo
Connection conn=null; z/+{QBen8
PreparedStatement ps=null; EPH
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try{ +or<(%o @
conn = DBUtils.getConnection(); OJ"./*H
conn.setAutoCommit(false); e ><0crb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); J _dgP[
for(int i=0;i<CountCache.list.size();i++){ {J
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CountBean cb=(CountBean)CountCache.list.getFirst(); 3N-pND0>p
CountCache.list.removeFirst(); $[Z~BfSQ
ps.setInt(1, cb.getCountId()); 2"?D aX
ps.executeUpdate();⑴ SepwMB4@
//ps.addBatch();⑵ J'sa{/
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} #+p-
//int [] counts = ps.executeBatch();⑶ FG[rH]
conn.commit(); M;Pry3J
}catch(Exception e){ >W8"Ar
e.printStackTrace(); 1P[x.t#
} finally{ 8U(o@1PT
try{ >V?0#f45@
if(ps!=null) { h'};spv
ps.clearParameters(); (E)hEQ@8
ps.close(); `7w-_o
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ps=null; D-LOjMe
} I=#`8deH(
}catch(SQLException e){} k9OGnCW\
DBUtils.closeConnection(conn); "FA.T7G
} 7@>/O)>(AS
} ]b;m~|9
public long getLast(){ x x>hJ!
return lastExecuteTime; #"KC29!Yj
} !hZ:
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public void run(){ &nXE?-J
long now = System.currentTimeMillis(); VqV [ @[P
if ((now - lastExecuteTime) > executeSep) { hXth\e\[{`
//System.out.print("lastExecuteTime:"+lastExecuteTime); / @"{u0
//System.out.print(" now:"+now+"\n"); pXl[I;
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); |@'O3KA
lastExecuteTime=now; /P@%{y
executeUpdate(); cZ?$_;=
} ~`QoBZ.O&
else{ <fG\J
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); S}VS@KDO
} V=*^C+6s
} P'OvwA
} (1[59<cg]
//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 FMeBsI9pL
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类写好了,下面是在JSP中如下调用。 El5} f4sl
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<% cbyzZ#WRb
CountBean cb=new CountBean(); c?HUW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ^@AyC"K
CountCache.add(cb); -)oUb=Lk{
out.print(CountCache.list.size()+"<br>"); [ ,Go*r
CountControl c=new CountControl(); }' AY#g
c.run(); #l4T/`u'9!
out.print(CountCache.list.size()+"<br>"); EZ .3Z`
%>