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: u;;]S!:M
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CountBean.java vU&gFEWg
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/* M}3>5*!=
* CountData.java }-YD_Pm
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* 5\RKT)%X
* Created on 2007年1月1日, 下午4:44 pA4oy
* ;lnh;0B
* To change this template, choose Tools | Options and locate the template under ;R 'OdQ$o
* the Source Creation and Management node. Right-click the template and choose w6v P
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* Open. You can then make changes to the template in the Source Editor. A)s
*/ om9fg66
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package com.tot.count; bU(t5
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/** Kh'/Ne?
* 5;C+K~Y
* @author jsfyNl?6
*/ :Y~fPke
public class CountBean { IHMZE42
private String countType; RY&Wvkjh
int countId; ;' YM@n
/** Creates a new instance of CountData */ 1k3wBc5<
public CountBean() {} * t{A=Wk
public void setCountType(String countTypes){ &*/8Ojv)9
this.countType=countTypes; E(>RmPP=7
} [:TOU^
public void setCountId(int countIds){ tDF6%RG
this.countId=countIds; ``$At ,m
} {pE")O7~P
public String getCountType(){ =H3 JRRS
return countType; c_vj't
} N:\I]M
public int getCountId(){ R0,
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return countId; srO{Ci0
} HG5|h[4Gt
} 1E=%:? d
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CountCache.java s>76?Q:i
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/* \y"!`.E7\d
* CountCache.java TOeJnk
* c+Ejah+
* Created on 2007年1月1日, 下午5:01 -Q<3Q_
* ]?/[& PP,
* To change this template, choose Tools | Options and locate the template under 8L9xP'[^
* the Source Creation and Management node. Right-click the template and choose HBV~`0O$
* Open. You can then make changes to the template in the Source Editor. p4bQCI
*/ &5)Kg%r
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package com.tot.count; !2>gC"$nv
import java.util.*; :|EM1-lwf
/** U[u9RB
* n*{e0,gp`
* @author !!%vs
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*/ u
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public class CountCache { w%GEOIj}
public static LinkedList list=new LinkedList(); .3 m^yo
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/** Creates a new instance of CountCache */ ~^w;`~L
public CountCache() {} ? D2:'gg
public static void add(CountBean cb){ ]SFB_5Gb
if(cb!=null){ 90Jxn'>^
list.add(cb); `LEk/b1(P
} %o.{h
} GL(R9Y
} {~.h;'m
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CountControl.java sX^m1v~N|
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/* /<\>j+SC
* CountThread.java w*e O9k
* 66,?f<b
* Created on 2007年1月1日, 下午4:57 ICTl{|i ]
* [Z`q7ddd^
* To change this template, choose Tools | Options and locate the template under L*6Tz'Qp
* the Source Creation and Management node. Right-click the template and choose W+ Z]
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* Open. You can then make changes to the template in the Source Editor. Z6
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*/ Ha)eeE$
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package com.tot.count; MR:Co4(
import tot.db.DBUtils; {()8 Wr
import java.sql.*; lGwX.cA!'
/** LBk1Qw}-
* hvnZ
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* @author RM|<(kq
*/ >t.2!Z_RQ
public class CountControl{ 5lu620o
private static long lastExecuteTime=0;//上次更新时间 KcF2}+iM
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 xwW[6Ah
/** Creates a new instance of CountThread */ Ie`kzssM
public CountControl() {} H^Ik FEVs
public synchronized void executeUpdate(){ =mxmJFA
Connection conn=null; vq
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PreparedStatement ps=null; L0/0<d(K
try{ s_yY,Z:
conn = DBUtils.getConnection(); }Gqx2 )H
conn.setAutoCommit(false); }b~;x6
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); MW=2GhD=
for(int i=0;i<CountCache.list.size();i++){ Ji\8(7
{8
CountBean cb=(CountBean)CountCache.list.getFirst(); \h~;n)FI
CountCache.list.removeFirst(); Ratg!l|'-
ps.setInt(1, cb.getCountId()); 8j. 9Sk/
ps.executeUpdate();⑴ hub1rY|No
//ps.addBatch();⑵ Mf^ ;('~
} 40<ifz[7
//int [] counts = ps.executeBatch();⑶ /0>Cy\eN0
conn.commit(); MoIVval/
}catch(Exception e){ RAxAy{
e.printStackTrace(); CTv-$7#
} finally{ [R iCa
try{ MM"{ehd{^a
if(ps!=null) { a.L ?J
ps.clearParameters(); 2VyLt=mdh
ps.close(); f*04=R?w7>
ps=null; H,9e<x#own
} 0%7c?3#
}catch(SQLException e){} n a])bBn
DBUtils.closeConnection(conn); d nWh}!
} \/*r45!
} q%i2'yE
public long getLast(){ `PnB<rf:*1
return lastExecuteTime; 44B)=p7
} ):E4qlB
public void run(){ m/r4f279
long now = System.currentTimeMillis(); Dtl381F J
if ((now - lastExecuteTime) > executeSep) { ^|5bK_Z&
//System.out.print("lastExecuteTime:"+lastExecuteTime); )s4#)E1
//System.out.print(" now:"+now+"\n"); ,kfUlv=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ;]34l."85
lastExecuteTime=now; m;)[gF
executeUpdate(); $/ew'h9q
} }@_F( B
else{ Ouc=4'$-
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); EtK,C~C}8
} W!
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} <ppM\$
} =ltT6of@o
//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 ]e@'9`G-'
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类写好了,下面是在JSP中如下调用。 % zHsh
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<% WBLfxr
CountBean cb=new CountBean(); D|}
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); SE&J)Sj]
CountCache.add(cb); S-Mn
out.print(CountCache.list.size()+"<br>"); k)oD
CountControl c=new CountControl(); m!L&_Z|j
c.run(); %?1k}(qUeY
out.print(CountCache.list.size()+"<br>"); Jf{6'Ub
%>