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: <TVJ9l
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CountBean.java :6o%x0l
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/* (l%?YME
* CountData.java :,l16{^
* [y8(v ~H
* Created on 2007年1月1日, 下午4:44 C&yZ` [K
* !-)!UQ~|8
* To change this template, choose Tools | Options and locate the template under R[zN?
* the Source Creation and Management node. Right-click the template and choose *sldv
* Open. You can then make changes to the template in the Source Editor. i[[.1MnS
*/ F'|K>!H
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package com.tot.count; +\ftSm>
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/** ?;oJ=.T
* 8XYxyOl
* @author dDA8IW![S
*/ 8SU0q9X.
public class CountBean { FdE?uw
private String countType; }>M\iPO.]*
int countId; 2pmj*Y3"8
/** Creates a new instance of CountData */ .tKBmq0xo"
public CountBean() {} +@]k[9
public void setCountType(String countTypes){ 6~sU[thGW
this.countType=countTypes; eyh}O
} \)5mO 8w
public void setCountId(int countIds){ ' Z#_"s#L
this.countId=countIds; 9{4oz<U
} AmC9qk8Q
public String getCountType(){ c$,1j%[)
return countType; {96MfhkeBv
} lusUmFm'*
public int getCountId(){ >yKz8SV#
return countId; #/ePpSyD
} 7k,BE2]"
} TrzAgNt
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CountCache.java LU;zpXg\
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/* zWU]4;,"
* CountCache.java q6rkp f,Tl
* }F0<8L6%
* Created on 2007年1月1日, 下午5:01 kJl^,q
* (/nnN4\=
* To change this template, choose Tools | Options and locate the template under T16gq-h'
* the Source Creation and Management node. Right-click the template and choose ROn@tW
* Open. You can then make changes to the template in the Source Editor. bK!h{Rr
*/ L7{}`O/g7
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package com.tot.count; LI@BB:)[
import java.util.*; SF-E>s!XL
/** .]h/M,xg
* z/"*-+j
* @author ~b*]jZwT
*/ y akRKiz\
public class CountCache { MvZa;B
public static LinkedList list=new LinkedList(); a(6h`GHo
/** Creates a new instance of CountCache */ &-qQF`7
public CountCache() {} 8#JX#<HEo
public static void add(CountBean cb){ ?R)dxuj
if(cb!=null){ tqpO3
list.add(cb); &~+QPnI>Pm
} xE;O =mI
} *GoTN
} izcaWt3 a
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CountControl.java Dq~;h \='
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/* 9MfU{4:;I
* CountThread.java Z6${nUX
* >Y8\f:KQ
* Created on 2007年1月1日, 下午4:57 @:Zk,
* MZ$uWm`/
* To change this template, choose Tools | Options and locate the template under h_#=f(.'j
* the Source Creation and Management node. Right-click the template and choose 5\z<xpJ
* Open. You can then make changes to the template in the Source Editor. ;<Z6Y3>I8
*/ In_"iEo,
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package com.tot.count; 8O]`3oa>
import tot.db.DBUtils; s.bo;lk
import java.sql.*; R`c[?U
/** {rR(K"M
* R6(:l;
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* @author zsJ# CDm
*/ #PD6LO
public class CountControl{ ) %Fwfb
private static long lastExecuteTime=0;//上次更新时间 q 7%p3
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 =w+8q1!o
/** Creates a new instance of CountThread */ ,9bnR;f\
public CountControl() {} A`Dx]y
public synchronized void executeUpdate(){ o:Kw<z,$H
Connection conn=null; 4{F1GW
PreparedStatement ps=null; '+_>PBOc
try{ [-$
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conn = DBUtils.getConnection(); ?'P}ZC8P
conn.setAutoCommit(false); PX|@D_%Y=
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); G~<UP(G
for(int i=0;i<CountCache.list.size();i++){ `Fn"QL-
CountBean cb=(CountBean)CountCache.list.getFirst(); lcZ.}
CountCache.list.removeFirst(); ;WSW&2
ps.setInt(1, cb.getCountId()); ~I5hV}ZT
ps.executeUpdate();⑴ vO1; ;
//ps.addBatch();⑵ aq$ hE-{28
} @Iz]:@\cJ
//int [] counts = ps.executeBatch();⑶ #3qeRl
conn.commit(); ).5X
}catch(Exception e){ k B>F(^
e.printStackTrace(); d{4;qM#
} finally{ +>q#eUS)
try{ d>hv-nD
if(ps!=null) { ^-Od*DTL
ps.clearParameters(); hU#e\L 7
ps.close(); mtv8Bm=<
ps=null; ;yJ:W8U]+;
} |[>@Kk4
}catch(SQLException e){} 3^y(@XFt
DBUtils.closeConnection(conn); 1.!U{>$
} tVn?cS
} p +i1sY
public long getLast(){ cFL~<
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return lastExecuteTime; SQ>i:D;
} yQ2=d5'V`
public void run(){ zi-_ l
long now = System.currentTimeMillis(); '}_r/l]K
if ((now - lastExecuteTime) > executeSep) { B'}?cG]
//System.out.print("lastExecuteTime:"+lastExecuteTime); O]u'7nO{{
//System.out.print(" now:"+now+"\n"); +&
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); {.:$F3T
lastExecuteTime=now; SB\%"nnV
executeUpdate(); q7X]kr*qx
} aas.-NT
else{ eQbHf
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W" 5nS =d%
} /\8Il+0
}
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} I'uwJy_I\
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 /}? 7Eni
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类写好了,下面是在JSP中如下调用。 X$Vi=f vt
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<% EA& 3rI>U)
CountBean cb=new CountBean(); zK<af
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \/NF??k,jk
CountCache.add(cb); U[C4!k:0
out.print(CountCache.list.size()+"<br>"); y}odTeq
CountControl c=new CountControl(); ^dQ{vL@9b9
c.run(); Y9+_MxC"
out.print(CountCache.list.size()+"<br>"); x|6]+?l@6
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