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: X,/@#pSOz
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CountBean.java ?wps_XU
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/* [)`9euR%
* CountData.java *|x2"?d-F:
* -#b-@sD
* Created on 2007年1月1日, 下午4:44 -;z&">
* Q^v8n1
* To change this template, choose Tools | Options and locate the template under *n0k2 p
* the Source Creation and Management node. Right-click the template and choose WT!8.M;Kv
* Open. You can then make changes to the template in the Source Editor. #[*e$C
*/ <?P UF,
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package com.tot.count; /h0<0b?i
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/** {sy#&m(el
* g
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* @author u pf7:gk +
*/ [?BmW{*u.
public class CountBean { 2I:vie
private String countType; b9(d@2MtK
int countId; Y#c11q Z
/** Creates a new instance of CountData */ E~zLhJTUL'
public CountBean() {} IPcAE!h6zN
public void setCountType(String countTypes){ k6~k
this.countType=countTypes; :&`Yz
} q<}5KY
public void setCountId(int countIds){
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this.countId=countIds; ?Z]}G
} \1RQ),5 %]
public String getCountType(){ cW),Y|8
return countType; !+ IxPn
} U<eVLfSij
public int getCountId(){ Y[;Pl$
return countId; +I2P{7
} pM\)f
} B4&@PX"'>,
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CountCache.java tqrvcnQr^
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/* /'G'GQrr
* CountCache.java (@M=W.M#
* [*?P2.b f
* Created on 2007年1月1日, 下午5:01 #l-,2C~
* ']f]:X;6w
* To change this template, choose Tools | Options and locate the template under T~%5^+[h
* the Source Creation and Management node. Right-click the template and choose 7F3Hkvd[k
* Open. You can then make changes to the template in the Source Editor. i,ku91T
*/ Yh:*.@
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package com.tot.count; 0(3t#
import java.util.*; G4s!q1H
/** *E.{i
* (EUX>IJ
* @author K;-:C9@
*/ V:!fe+Er
public class CountCache { h|%d=`P,
public static LinkedList list=new LinkedList(); %M9^QHyo@
/** Creates a new instance of CountCache */ [}lv!KmzW
public CountCache() {} e?L$RY,7
public static void add(CountBean cb){ i(,R$AU
if(cb!=null){ K]@^8e$(
list.add(cb); t2+m7*76
} nI.#A
} rN{&$+"2
} +U+c]Xgt
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CountControl.java _J
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/* c.&vWmLSGE
* CountThread.java jRB:o?S
* cY#TH|M
* Created on 2007年1月1日, 下午4:57 ~AK!_EOs`
* ;'tsdsu}
* To change this template, choose Tools | Options and locate the template under `"(7)T{
* the Source Creation and Management node. Right-click the template and choose /Rk5n
* Open. You can then make changes to the template in the Source Editor. 3Luv$6
*/ :":W(O
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package com.tot.count; 0+r/>-3]
import tot.db.DBUtils; HK&F'\'}
import java.sql.*; Z/;rM8[{&
/** wC=IN
* K
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* @author ;=)CjC8)
*/ )l30~5u<J
public class CountControl{ f*5=,$0
private static long lastExecuteTime=0;//上次更新时间 A1%V<im@Z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TmX~vZ
/** Creates a new instance of CountThread */ ,[Cl 'B
public CountControl() {} [b;Oalw
public synchronized void executeUpdate(){ Ylt[Ks<2
Connection conn=null; %F&j B
PreparedStatement ps=null; g:;v]
try{ S3qUzK
conn = DBUtils.getConnection(); g"C$B Fc
conn.setAutoCommit(false); r7ywK9UL
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); tk}qvW.Ii
for(int i=0;i<CountCache.list.size();i++){ ,*S?L
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CountBean cb=(CountBean)CountCache.list.getFirst(); 3tIIBOwg[
CountCache.list.removeFirst(); 1oX"}YY1
ps.setInt(1, cb.getCountId()); z^}T=
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ps.executeUpdate();⑴ #|$i H kVY
//ps.addBatch();⑵ yo
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} |[o2S9 0
//int [] counts = ps.executeBatch();⑶ r*+9<8-ZX<
conn.commit(); &% M^:WT
}catch(Exception e){ 0U`Ic_.
e.printStackTrace(); Jz%&-e3
} finally{ B}P,sFghw
try{ eX_}KH-Q
if(ps!=null) { tinN$o
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ps.clearParameters(); =/dW5qy;*+
ps.close(); gdCU1D\
ps=null; {_[l,tdZ
} 3\mFK$#sr
}catch(SQLException e){} i,4JS,82I
DBUtils.closeConnection(conn); 7BI0g@$Nn]
} R>gj"nB
} y-sQ"HPN
public long getLast(){ M9f*7{c
return lastExecuteTime; u%}vTCg*p
} )[nzmL*w
public void run(){ t'9E~_!C
long now = System.currentTimeMillis(); *[yCcqN.
if ((now - lastExecuteTime) > executeSep) { qKO\;e*
//System.out.print("lastExecuteTime:"+lastExecuteTime); wc__g8?'
//System.out.print(" now:"+now+"\n"); UdL`.D,
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 2s6Vy
lastExecuteTime=now; S~6<'N&[
executeUpdate(); HHEFX9u
} Iv/yIS
else{ `+zr PpX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} Xd|5{
} 3tLh{S?uJ
} ;WGY)=-gv
//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 ^Gd<miw
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类写好了,下面是在JSP中如下调用。 n:<avl@o<
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<% CSsb~/Oxu
CountBean cb=new CountBean(); t 8M3VGN
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); `b7o
CountCache.add(cb); #Wc)wL-Tg
out.print(CountCache.list.size()+"<br>"); zNXkdw
CountControl c=new CountControl(); cPS!%?}I
c.run(); 7B&nV92S
out.print(CountCache.list.size()+"<br>"); Ip2JzE
%>