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: i2YuOV!
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CountBean.java XKttZOiGT
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/* #PanfYR
* CountData.java H!nr^l'+
* AW_(T\P:u
* Created on 2007年1月1日, 下午4:44 [*H N"
* C>$E%=h+_
* To change this template, choose Tools | Options and locate the template under e7(ucE
* the Source Creation and Management node. Right-click the template and choose ]2'na?q9
* Open. You can then make changes to the template in the Source Editor. #iWSDy
*/ =fve/_Q~
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package com.tot.count; 9@52Fg;mj
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/** ->O2I?
* 7J|VD#DE$Y
* @author kRD%b[*d
*/ PSVc+s[Q+V
public class CountBean { %8Dzo
private String countType; H5]^
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int countId; 7#U^Dx\yh
/** Creates a new instance of CountData */ %Gj8F4{
public CountBean() {} 0B&Y]*
public void setCountType(String countTypes){ ~aOuG5XK
this.countType=countTypes; )m{Ye0!RD
} @@rEs40
public void setCountId(int countIds){ (85Fv&a
this.countId=countIds; I_%a{$Gjl
} Z]WnG'3N
public String getCountType(){ f=!VsR2o
return countType; 'd&0Js$^
} $w0lrh[+
public int getCountId(){ WN5`;{\
return countId; Ck@J,~x1D
} 3a 1 u
} n;p:=\uN
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CountCache.java D8nD/||;Z
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/* =w5O&(
* CountCache.java pM&YXb?
* ?N=m<fn
* Created on 2007年1月1日, 下午5:01 ;Y mTw
* gEhN3(
* To change this template, choose Tools | Options and locate the template under >,gvb5
* the Source Creation and Management node. Right-click the template and choose U{$1[,f
* Open. You can then make changes to the template in the Source Editor. E)-r+ <l
*/ Ev2HGU [
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package com.tot.count; Gqcz<=/
import java.util.*; l?DJJ|> O
/** 6^n0[7
* m6yIR6H
* @author je4 w=]JV
*/ |Uk"
{
public class CountCache { @@g\2Gs
public static LinkedList list=new LinkedList(); 9F-
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/** Creates a new instance of CountCache */ y}K\%;`[a
public CountCache() {} ;.Ie#Vr1N
public static void add(CountBean cb){ Ty@=yA17
if(cb!=null){ /.eeO k
list.add(cb); 8dOo Q
} bo=ZM9
} %tt%`0
} {"H2 :-t<
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CountControl.java omf Rs
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/* ]$
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* CountThread.java c<BO gNr
* "SoHt]%#
* Created on 2007年1月1日, 下午4:57 }o,z!_^PLQ
* ~;OYtz
* To change this template, choose Tools | Options and locate the template under /_-;zL
* the Source Creation and Management node. Right-click the template and choose x/MZ(A%D
* Open. You can then make changes to the template in the Source Editor. w$5A|%Y+V}
*/ zggB$5
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package com.tot.count; Ti;Ijcq8
import tot.db.DBUtils; PaCzr5!~f
import java.sql.*; X#UMIlU
/** ~ZlC
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* ]Lqt(c
* @author !sA_?2$
*/ hsG#6?l3
public class CountControl{ ])#\_'fg
private static long lastExecuteTime=0;//上次更新时间 |__=d+M'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )I@L+
/** Creates a new instance of CountThread */ nxap\Lf
public CountControl() {} n1:v HBM@\
public synchronized void executeUpdate(){ Er:?M_ev
Connection conn=null; {sv{847V
PreparedStatement ps=null; ^yKY'>T#d
try{ } i)$n(A)K
conn = DBUtils.getConnection(); gZSi\m>
conn.setAutoCommit(false); 1k({(\>qq
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ," R_ve
for(int i=0;i<CountCache.list.size();i++){ . M$D
CountBean cb=(CountBean)CountCache.list.getFirst(); f#MN-1[67
CountCache.list.removeFirst(); {XW>:EU'N
ps.setInt(1, cb.getCountId()); )q-!5^ak
ps.executeUpdate();⑴ 0R%58,R
//ps.addBatch();⑵ Y)RikF >
} \Nyxi7
//int [] counts = ps.executeBatch();⑶ 0P
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conn.commit(); 7[ji,.7
}catch(Exception e){ Ro$XbU)
e.printStackTrace(); h2<$L
} finally{ 7!)%%K.z6
try{ ir?9{t/()
if(ps!=null) { Z:Am\7 I
ps.clearParameters(); _xsYcw~)
ps.close(); |sAg@kM
ps=null; \OH:xW~
} $^>vJk<
}catch(SQLException e){} @SXgaWr
DBUtils.closeConnection(conn); N `MQHQ1
} mg]dK p
} u9(AT>HxT
public long getLast(){ &[pwLYf7
return lastExecuteTime; gQwmYe
} T]`"
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public void run(){ .ji%%f
long now = System.currentTimeMillis(); }hxYsI"d
if ((now - lastExecuteTime) > executeSep) { sJ=B:3jS0
//System.out.print("lastExecuteTime:"+lastExecuteTime); mD3#$E!A1
//System.out.print(" now:"+now+"\n"); y0]O 6.{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _aYQ(FO
lastExecuteTime=now; v<W++X7z
executeUpdate(); i=@*F$,
} "?-s
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else{ (ShJ!
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); !hUyX}{`j
} f0+
} 6WZp&pO
} KivzgNz
//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 6yqp<D0SP)
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类写好了,下面是在JSP中如下调用。 T8LwDqio
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<% uDR(^T{g#
CountBean cb=new CountBean(); v3Kqs:"\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); yFjSvm6
CountCache.add(cb); Y!zlte|P
out.print(CountCache.list.size()+"<br>"); #q%/~-Uk
CountControl c=new CountControl(); gO%3~f!vY#
c.run(); |>)mYLN!y
out.print(CountCache.list.size()+"<br>"); >b0}X)Z+U
%>