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: [wkSY>Gu
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CountBean.java uY;7&Lw
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/* cgV5{|P
* CountData.java 1lLXu
* ET\>cxSp
* Created on 2007年1月1日, 下午4:44 werTwe2Q
* E0t%]?1
* To change this template, choose Tools | Options and locate the template under UA3!28Y&E3
* the Source Creation and Management node. Right-click the template and choose W.sH
* Open. You can then make changes to the template in the Source Editor. /Z1>3=G by
*/ !QsmT3
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package com.tot.count; Dzr(Fb
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/** ?mbI6fYv
* nd)`G$gL
* @author jBr3Ay@<
*/ .22}=z
public class CountBean { 'GF <_3I2l
private String countType; "ivSpec.V
int countId; ]N^>>k
/** Creates a new instance of CountData */ 0f;`Zj0l8
public CountBean() {} R^VmNj
public void setCountType(String countTypes){ Ae8P'FWB>
this.countType=countTypes; [A'9sxG
} rCsH
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public void setCountId(int countIds){ {fxytiH8
this.countId=countIds; :F.eyA|#@G
} LTZ~Id-)P
public String getCountType(){ $_+.D`vx`
return countType; )Im3';qt
} _edT+r>+
public int getCountId(){ 2#_i_j
return countId; 7Um3myXU
} T]lVwj
} HV[*=Qi
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CountCache.java
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/* =
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* CountCache.java |bX{MF
* F3=iyiz6
* Created on 2007年1月1日, 下午5:01 ? oQ_qleuo
* Y;1J`oT
* To change this template, choose Tools | Options and locate the template under nV_[40KP_
* the Source Creation and Management node. Right-click the template and choose ^$;5ZkQy
* Open. You can then make changes to the template in the Source Editor. !=p^@N7
*/ .B_a3K4'{^
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package com.tot.count; l~#%j( Yo
import java.util.*; '-[?iF@l
/** uuf+M-P
* _xdFQ
* @author dk.VH!uVb
*/ u;/<uV3
public class CountCache { KY9&Ky+2 B
public static LinkedList list=new LinkedList(); 9;L50q>s
/** Creates a new instance of CountCache */ ~PA6e+gmL
public CountCache() {} *3h!&.zm
public static void add(CountBean cb){ .]LP327u
if(cb!=null){ 9V?:!%J
list.add(cb); ,K8(D<{
} =P`l+k3
} V~4yS4
} *GC9o/
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CountControl.java ^ Iy'<J
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/* QvDD
* CountThread.java 4^{~MgQWK+
* GcHZ&m4
* Created on 2007年1月1日, 下午4:57 b\^9::oY
* 2@?\"kR"!
* To change this template, choose Tools | Options and locate the template under U,tWLX$@
* the Source Creation and Management node. Right-click the template and choose vx4Jk]h+=L
* Open. You can then make changes to the template in the Source Editor. :M\3.7q
*/ I7HP~v~
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package com.tot.count; t4FaU7
import tot.db.DBUtils; 5tcJTz
import java.sql.*; >OW>^%\!1
/** r=:o$e
* x>MY_?a
* @author a{!
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*/ 0RkiD8U5
public class CountControl{ =Y<RG"]a&J
private static long lastExecuteTime=0;//上次更新时间 nhI1`l&
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 7gP8K`w?[
/** Creates a new instance of CountThread */ t(\P8J
public CountControl() {}
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public synchronized void executeUpdate(){ t'DYT"3
Connection conn=null; rRd8W}B
PreparedStatement ps=null; wf/DLAC
try{ hG
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conn = DBUtils.getConnection(); tN&_f==e
conn.setAutoCommit(false); &?#!%Ds
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Fa9gr/.F,@
for(int i=0;i<CountCache.list.size();i++){ |<w
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CountBean cb=(CountBean)CountCache.list.getFirst(); 4<l&cP
CountCache.list.removeFirst(); p WLFJH}N
ps.setInt(1, cb.getCountId()); UkgiSv+
ps.executeUpdate();⑴ /+{1;}AT
//ps.addBatch();⑵ O>Ao#_*hOb
} <"}WpT
//int [] counts = ps.executeBatch();⑶ >
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conn.commit(); ZE"Z_E;r
}catch(Exception e){ :Wmio\
e.printStackTrace(); (VH0+
} finally{ v@;!fBUt
try{ (g#,AX
if(ps!=null) { $S{]` +
ps.clearParameters(); sA[eKQjaD
ps.close(); -?PXj)<
ps=null; -A;4""
} "M4gl
}catch(SQLException e){} Ilv
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DBUtils.closeConnection(conn);
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} &Ez]pKjB
} riY[p,
public long getLast(){ ma7@vD
return lastExecuteTime; ;sfk@ec
} E|5lm
public void run(){ drEND`,@6|
long now = System.currentTimeMillis(); Yn1CU
if ((now - lastExecuteTime) > executeSep) { Fc.1)yh.
//System.out.print("lastExecuteTime:"+lastExecuteTime); :}}~ $$&
//System.out.print(" now:"+now+"\n"); BZ-)XF'4
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); xH/Pw?^
lastExecuteTime=now; &s<'fSI
executeUpdate(); /6d:l>4
} 0
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else{ ;OY*`(Id
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); N77EM
} $][$ e
} QP0[
} n
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//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 {ZrB,yK
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类写好了,下面是在JSP中如下调用。 t}2$no?
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<% _
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CountBean cb=new CountBean(); a~"<lzu|$
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); *d;D~"E<@
CountCache.add(cb); }~3 %KHT
out.print(CountCache.list.size()+"<br>"); R8YA"(j!L
CountControl c=new CountControl(); h!UB#-
c.run(); /ng+IC3
out.print(CountCache.list.size()+"<br>"); Q^z&;%q1
%>