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: [z+YXs!N
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CountBean.java C dPQhv)m
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/* VM\\.L
* CountData.java 0Zo><=
* vv<\LN0
* Created on 2007年1月1日, 下午4:44 -yg;,nCg
* NYs<`6P:Y
* To change this template, choose Tools | Options and locate the template under D/%v/mpj$
* the Source Creation and Management node. Right-click the template and choose >i.$s
* Open. You can then make changes to the template in the Source Editor. jO|`aUYTf
*/ ,Mi'NO
/BvMNKb$$
package com.tot.count; TcJJ"[0
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/** ZrA*MN
* (x.qyYEoI
* @author Fi\)ka\u
*/ |ITb1O`_P
public class CountBean { x2aG5@<3
private String countType; gTB|IcOs
int countId; b`^?nD7
/** Creates a new instance of CountData */ 8x7TK2r
public CountBean() {} [;F!\B-
public void setCountType(String countTypes){ <S6?L[_
this.countType=countTypes; .h4Z\R`
} v)nv"o[
public void setCountId(int countIds){ {#`wW`U^
this.countId=countIds; R~hIo aiN
} #UI`+2w
public String getCountType(){ Yl$@/xAa
return countType; [fb9;,x`
} Zy:q)'D=
public int getCountId(){ OT6Te&
return countId; 9.( [,J
} $vYy19z
} a>,_o(]cW
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CountCache.java *ezft&{)`
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/* 5nceOG8
* CountCache.java Nlwt}7
* Z("N
*`VP;
* Created on 2007年1月1日, 下午5:01 \_(0V"
* eWD!/yr|
* To change this template, choose Tools | Options and locate the template under _D8 zKp
* the Source Creation and Management node. Right-click the template and choose ;pfN
* Open. You can then make changes to the template in the Source Editor. FYefn3b
*/ .'2I9P\!
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package com.tot.count; AE`{k-3=%
import java.util.*; Qm"~XP
/** ;:J"- p
*
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* @author `_ZbA#R,
*/ 48G^$ T{
public class CountCache { BC1smSlJ
public static LinkedList list=new LinkedList(); @ptrF
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/** Creates a new instance of CountCache */ [O!/hppN
public CountCache() {} ?6x&A t
public static void add(CountBean cb){ yGC
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if(cb!=null){ }NdLd!
list.add(cb); |o(te
} f.oY:3h:
} xUa9>=JU{
} UCFFF%
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CountControl.java l^}5PHLd
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/* SNSoV3|k-
* CountThread.java 00y(E@~
* VAyAXN~
* Created on 2007年1月1日, 下午4:57 ~YviXSW
* j>v8i
bS(
* To change this template, choose Tools | Options and locate the template under {CVZ7tU7]
* the Source Creation and Management node. Right-click the template and choose C$LRX7Z`o
* Open. You can then make changes to the template in the Source Editor. X9^q-3&60
*/ bmKvvq
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package com.tot.count; 0D `9
import tot.db.DBUtils; bun_R-
import java.sql.*; pjSM7PhQ
/** ?G]yU
* #,})N*7
* @author gQY`qz
*/ _ |HA\!
public class CountControl{ $`0,N_C<}
private static long lastExecuteTime=0;//上次更新时间 M;KeY[u
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 u3UN
/** Creates a new instance of CountThread */ =_Z.x&fi
public CountControl() {} j"zW0g!S
public synchronized void executeUpdate(){ ;>X;cZMd
Connection conn=null; _)3C_G1!
PreparedStatement ps=null; j-FMWEp
try{ ('d,Sh
conn = DBUtils.getConnection(); JlEfUg#*
conn.setAutoCommit(false); 1UB.2}/:
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); B/hQvA;(
for(int i=0;i<CountCache.list.size();i++){ ?A*<Z%}1?
CountBean cb=(CountBean)CountCache.list.getFirst(); A4;~+L :M
CountCache.list.removeFirst(); 5C*-v,hF
ps.setInt(1, cb.getCountId()); A
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ps.executeUpdate();⑴ b0se-#+
//ps.addBatch();⑵ 07ppq?,y
} puEu)m^
//int [] counts = ps.executeBatch();⑶ n}4q2x"
conn.commit(); 9~K+h/
}catch(Exception e){ &/otoAr(
e.printStackTrace(); _ph1( !H$
} finally{ j^f54Ky.
try{ Gs04)KJm<
if(ps!=null) { $h=v;1"
ps.clearParameters(); vJx( lU`Y
ps.close(); 8Vt'X2
ps=null; {\LLiU}MJC
} WBzPSnS2
}catch(SQLException e){} L`rrT
DBUtils.closeConnection(conn); EgzdRB\Cf
} +#X+QG
} 9]/:B8k
public long getLast(){ >29c[O"[
return lastExecuteTime; F^}d>2W(
} L}g#h+GP[
public void run(){ /&c>*4)
long now = System.currentTimeMillis(); bV#j@MJ~0
if ((now - lastExecuteTime) > executeSep) { n1'i!NWt
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7s}F`fjKP
//System.out.print(" now:"+now+"\n"); 1h)K3cC
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Hbu
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lastExecuteTime=now; $"0`2C
executeUpdate(); 'S#^70kt
} n2[h`zm1{B
else{ 2IkyC`
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }ZiJHj'<
} `\=~
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} 6hXh;-U
} jD6T2K7i
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 P4E_<v[
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类写好了,下面是在JSP中如下调用。 _,p/2m-Pj
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<% B.gEV*@
CountBean cb=new CountBean(); CT<z1)#@^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "
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CountCache.add(cb); ?dCJv_w
out.print(CountCache.list.size()+"<br>"); ~BnmAv$m[
CountControl c=new CountControl(); X|R"8cJ
c.run(); m YhDi
out.print(CountCache.list.size()+"<br>"); %UV"@I+
%>