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: 0R[onPU_vZ
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CountBean.java E A}Vb(2
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/* sQ8_j
* CountData.java +p#Q|o'
* l4`HuNR1
* Created on 2007年1月1日, 下午4:44 @-F[3`HeA
* lL{1wCsl
* To change this template, choose Tools | Options and locate the template under ~G*eJc0S:
* the Source Creation and Management node. Right-click the template and choose /QK H30E
* Open. You can then make changes to the template in the Source Editor. &fuJ%
*/ Bfz]PN78.G
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package com.tot.count; wSP'pM{#2
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/** 5u3SP?.&
* qD/X% `>Q
* @author .B|a.-oA4
*/ M<"H1>q@
public class CountBean { e[AwR?=
private String countType; xfJ&11fG2
int countId; K{#1O=Gi
/** Creates a new instance of CountData */ I3$/#
public CountBean() {} C~#ndl
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public void setCountType(String countTypes){ YoEL|r|
this.countType=countTypes; =ijVT_|u0
} )RE~=*?d
public void setCountId(int countIds){ o(_~
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this.countId=countIds; zP$Ef7bB
} ,Xt!dT-
public String getCountType(){ zBd)E21H
return countType; FY6!)/P0I7
} >s+TD4OfY
public int getCountId(){ 1}"PLq(
return countId; x%\m/_5w%
} Kgw_c:/'
} s$ v<p(yl
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CountCache.java G)'(%rl
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/* |w7D&p$
* CountCache.java N)H
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* ek3,ss3
* Created on 2007年1月1日, 下午5:01 ^w*$qzESy
* Zc Y* TGx
* To change this template, choose Tools | Options and locate the template under 21\t2<"
* the Source Creation and Management node. Right-click the template and choose !O-9W=NJ
* Open. You can then make changes to the template in the Source Editor. Skn2-8;10
*/ 7,![oY[
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package com.tot.count; wmf#3"n
import java.util.*; ?()$imb*
/** v%%;Cp73
* Wk"\aoX"E
* @author
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*/ OY>0qj
public class CountCache { 'K0=FPB/@
public static LinkedList list=new LinkedList(); 4M4oI .
/** Creates a new instance of CountCache */ hz8Z)xjJ V
public CountCache() {} V.k2t$@
public static void add(CountBean cb){ XK 09x1r
if(cb!=null){ z8"(Yy7m
list.add(cb); 9?xc3F2EBD
} \X?GzQkr
} 9uL="z$\
} yF#:*Vz>
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CountControl.java 6+;B2;*3
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/* \HsrUZ~
* CountThread.java [,1\>z|&
* 0,x<@.pW
* Created on 2007年1月1日, 下午4:57 EN!Q]O|
* :',Q6j( s
* To change this template, choose Tools | Options and locate the template under 7P2?SW^
* the Source Creation and Management node. Right-click the template and choose +UTs2*H/^
* Open. You can then make changes to the template in the Source Editor. u3>Dvl@
*/ s{]2~Z^2od
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package com.tot.count; edW:(19}
import tot.db.DBUtils; Z}
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import java.sql.*; 0f<$S$~h
/** ee=d*)
*
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* @author 1tNmiAu
*/ HYkZMVH{
public class CountControl{ pzPm(M1^X
private static long lastExecuteTime=0;//上次更新时间 l"-F<^
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 %?7j
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/** Creates a new instance of CountThread */ u9 yXHf
public CountControl() {} :$#";t|
public synchronized void executeUpdate(){ 9W[ ~c"Ku
Connection conn=null; I>jDM
PreparedStatement ps=null; ?\l@k(w4[x
try{ @6roW\'$
conn = DBUtils.getConnection(); HP
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conn.setAutoCommit(false); Rf~? u)h1
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?");
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for(int i=0;i<CountCache.list.size();i++){ X~Yj#@
CountBean cb=(CountBean)CountCache.list.getFirst(); 'Wn2+pd
CountCache.list.removeFirst(); >,v,4,c
ps.setInt(1, cb.getCountId()); -X6[qLq
ps.executeUpdate();⑴ l{7q(
//ps.addBatch();⑵ > $#v\8
} _Zq2 <:
//int [] counts = ps.executeBatch();⑶ NzP5s&,C69
conn.commit(); q-;z!iq|!
}catch(Exception e){ V+M=@Pvp9
e.printStackTrace(); #!WD1a?L
} finally{ AxOn~fZ!
try{ hu
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if(ps!=null) { {I2qnTN_a
ps.clearParameters(); e uF@SS
ps.close(); }4; \sY
ps=null; j/FFxlFNL
} Ba9le|c5
}catch(SQLException e){} iA^GA8dn
DBUtils.closeConnection(conn); XA$Z7_gu3
} b\U p(]
} tw`{\kWG
public long getLast(){ `oxs;;P
return lastExecuteTime; Of*z9YI
} ^@&RJa-kb
public void run(){ BpGK`0H
long now = System.currentTimeMillis(); h zh%ML3L
if ((now - lastExecuteTime) > executeSep) { %:P&!F\?
//System.out.print("lastExecuteTime:"+lastExecuteTime); d4h,
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//System.out.print(" now:"+now+"\n"); t&r-;sH^[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); zuR F6?un
lastExecuteTime=now; m),3J4(q
executeUpdate(); BAq@ H8*B
} 3+%c*}KC~
else{ "2}E ARa
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); RK*ZlD<
} dh~+0FZ{A
} <]u~;e57
} C>?`1d@
//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 Rr#vv
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类写好了,下面是在JSP中如下调用。 %Q}T9%Mtj
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<% K'`N(WiL
CountBean cb=new CountBean(); d `z),A=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); O=HT3gp&
CountCache.add(cb); .[Z<r>
out.print(CountCache.list.size()+"<br>"); Felu`@b
CountControl c=new CountControl(); 9Okb)K95
c.run(); QzwA*\G
out.print(CountCache.list.size()+"<br>"); BtyBZ8P;e
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