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: |rgp(;iO
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CountBean.java afw`Heaa2(
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/* Vk tc
* CountData.java CN{xh=2qY[
* tD~
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* Created on 2007年1月1日, 下午4:44 vg-Ah6BC{
* r4isn^g
* To change this template, choose Tools | Options and locate the template under =*5< w
* the Source Creation and Management node. Right-click the template and choose gTS}'w{
* Open. You can then make changes to the template in the Source Editor. k-Z:z?M
*/
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package com.tot.count; )ZW[$:wA
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/** Q}: $F{
* 8345
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* @author -O^R~Q_`w
*/ !X[P)/?b0+
public class CountBean { &7XsyDo6
private String countType; ri`;
int countId; E!9(6G4
/** Creates a new instance of CountData */ 4;bc!>
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public CountBean() {} yW)r`xpY
public void setCountType(String countTypes){ .6LlkM6[g
this.countType=countTypes; I7#^'/
} _P`
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public void setCountId(int countIds){ dBkM~"
this.countId=countIds; Dv*d$
} fm^J-
public String getCountType(){ |vw],r6
return countType; <N:)Xf9`
} n)j0h-
public int getCountId(){ D#D55X^6*
return countId; RW<10:
} ;Nw)zS
} Q Hr'r/0
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CountCache.java @6
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/* o-o -'0l
* CountCache.java [4hi/60
* r1Hh @sxn
* Created on 2007年1月1日, 下午5:01 I+F>^4_d
* "D'rsEh
* To change this template, choose Tools | Options and locate the template under #+N_wIP4
* the Source Creation and Management node. Right-click the template and choose A>8~deZ9
* Open. You can then make changes to the template in the Source Editor. }4T `)
*/ $NCR
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package com.tot.count; 2rW9ja
import java.util.*; #].qjOj
/** \*&?o51!e
* }d>Xh8:%)
* @author $@vB<(sk
*/ gnkeJ}K
public class CountCache { |
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public static LinkedList list=new LinkedList(); V'gJtF
/** Creates a new instance of CountCache */ o:&8H>(hn]
public CountCache() {} Ke:WlDf
public static void add(CountBean cb){ d>NO}MR
if(cb!=null){ lU%oU&P/"S
list.add(cb); XdmpfUR,13
} `zrg?
} Q@W!6]*\
} HI{h>g T
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CountControl.java `K:n=hpF
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/* tSux5yV
* CountThread.java 4Y}Nu
* IdMwpru(
* Created on 2007年1月1日, 下午4:57 xY/F)JOeG
* :iLRCK3C
* To change this template, choose Tools | Options and locate the template under nW*cqM%+
* the Source Creation and Management node. Right-click the template and choose $)$r
* Open. You can then make changes to the template in the Source Editor. ^pH8'^n
*/ /qJC p![X
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package com.tot.count; Mtv{37k~
import tot.db.DBUtils; H3*]}=
import java.sql.*; V?'p E
/** \<(EV,m2
* n$XEazUb0N
* @author :4-,Ru1C"
*/ +Adk1N8
public class CountControl{ ,*dLE
private static long lastExecuteTime=0;//上次更新时间 1pg#@h[|t
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \q*-9_M
/** Creates a new instance of CountThread */ 3[y$$qXI
public CountControl() {} jl>TZ)4}V
public synchronized void executeUpdate(){ J}[[tl
Connection conn=null; 9r+'DX?>
PreparedStatement ps=null; Ww60-d}}Q
try{ (sQXfeMz
conn = DBUtils.getConnection(); b9#(I~}
conn.setAutoCommit(false); S9r?= K
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); =Gu&0f
for(int i=0;i<CountCache.list.size();i++){ ?>U=bA
CountBean cb=(CountBean)CountCache.list.getFirst(); pDYJLh-C
CountCache.list.removeFirst(); TE$6=;
ps.setInt(1, cb.getCountId()); 9PA<g3z
ps.executeUpdate();⑴ wggB^ }~
//ps.addBatch();⑵ =cZ24I
} h@NC#Iod
//int [] counts = ps.executeBatch();⑶ M_Ag*?2I
conn.commit(); yyljyE
}catch(Exception e){ Ex
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e.printStackTrace(); >W8"Ar
} finally{ UO&$1rV
try{ $A9Pi"/*z
if(ps!=null) { [|1I.AZ{
ps.clearParameters(); /{`"X_.o
ps.close(); {&>rKCi
ps=null; \u{4=-C.
} "Kp#Lx
}catch(SQLException e){} #+l`tj4b/
DBUtils.closeConnection(conn); RG'76?z
} mi<Q3;m
} o
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public long getLast(){ 3p&T?E%
return lastExecuteTime; eGq7+
} L55UeP\
public void run(){ ur8+k4]\"
long now = System.currentTimeMillis(); qjhV/fsfb
if ((now - lastExecuteTime) > executeSep) { :=;{w~D
//System.out.print("lastExecuteTime:"+lastExecuteTime); }R#W<4:
//System.out.print(" now:"+now+"\n"); Ve|:k5z
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); f0sGE5
lastExecuteTime=now; PjEJC@n
executeUpdate(); 1J"9Y81
} g assOd
else{ b{
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); s+lBai*#
} B8T$<
} |mQ Fi\
} $U]T8;5Q
//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 #DFi-o&-
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类写好了,下面是在JSP中如下调用。 =oSd M2
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<% $\h-F8|JMX
CountBean cb=new CountBean(); ap}p?r
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); nS%jnp#
CountCache.add(cb); 2L 1,;
out.print(CountCache.list.size()+"<br>"); c#}K,joeU
CountControl c=new CountControl(); Q l)hIf$Oo
c.run(); i m;6$3
out.print(CountCache.list.size()+"<br>"); !Yb !Au[
%>