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: N1}r%!jk/
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CountBean.java ~g9~D}48k'
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/* d/3bE*gr
* CountData.java n/Dg)n?
* yIf^vx_G
* Created on 2007年1月1日, 下午4:44 i[4!% FxB
* {Hie%2V
* To change this template, choose Tools | Options and locate the template under r $[{sW
* the Source Creation and Management node. Right-click the template and choose VnqcpJ
* Open. You can then make changes to the template in the Source Editor. ?E,-P!&R
*/ n<P&|RTZ
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package com.tot.count; 8`s*+.LI!
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/** f9OY>|a9
* Y[|9
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* @author ahdwoB
*/ HWIn.ij
public class CountBean { \T[OF8yhW
private String countType; od$$g(
int countId; pHowioFx
/** Creates a new instance of CountData */ Wv%F^(R7
public CountBean() {} DQ}&J
public void setCountType(String countTypes){ V["'eJA,,
this.countType=countTypes; TV|Z$,6l
} G5|'uKz2"
public void setCountId(int countIds){ 9@?|rje9
this.countId=countIds; b'C#]DorE
} H2xDC_Fs
public String getCountType(){ KSJ+3_7]k
return countType; E@%1HO_
} z0x^HDAeC
public int getCountId(){ ^?_MIS`4N
return countId; (/^?$~m"
} S'`G7ht
} }
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CountCache.java +U<.MVOo.
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/* LN)yQ-
* CountCache.java ~c55LlO>
* ~Y{]yBGoF
* Created on 2007年1月1日, 下午5:01 x[fp7*TiG
* 7L!}F;yT
* To change this template, choose Tools | Options and locate the template under 0$NzRPbH
* the Source Creation and Management node. Right-click the template and choose nTw:BU4jd
* Open. You can then make changes to the template in the Source Editor. Bp5%&T k
*/ t<"`gM^|
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package com.tot.count; A6+qS
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import java.util.*; QCG-CzJ9l
/** ;dtA-EfOZ
* fLeHn,*,"
* @author q,_EHPc
*/ N?8nlrDQ
public class CountCache { Q-A_ 8
public static LinkedList list=new LinkedList(); iaQfxQP1w%
/** Creates a new instance of CountCache */ EiP N44(
public CountCache() {} ]T(qk
public static void add(CountBean cb){ oCLM'\
if(cb!=null){ E:O/=cT
list.add(cb); e\O625
} ADM!4L(s4}
} P8H2v_)X&
} l: kW|
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CountControl.java w11L@t[5W8
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/* +3M1^:
* CountThread.java ?v-!`J>EF#
* 1FG"Ak}D
* Created on 2007年1月1日, 下午4:57 $C,`^n'
* \rT>&o .i
* To change this template, choose Tools | Options and locate the template under c,]fw2
* the Source Creation and Management node. Right-click the template and choose s0CDp"uJY
* Open. You can then make changes to the template in the Source Editor. Z%b1B<u$
*/ ]ncK M?'O
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package com.tot.count; 1vAJ(O{-
import tot.db.DBUtils; + rM]RFi
import java.sql.*; +6~zMKp
/**
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* uKTYb#E7
* @author .g7\+aiTUd
*/ IGo5b-ds
public class CountControl{ 0+)1KU)I
private static long lastExecuteTime=0;//上次更新时间 @*uZ+$
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 D51s)?
/** Creates a new instance of CountThread */ zTl,VIa3p
public CountControl() {} J9f]=1`
public synchronized void executeUpdate(){ [g}0.J`_
Connection conn=null; ![eY%2;<
PreparedStatement ps=null; 1bDAi2 H
try{ &LG|YvMY6
conn = DBUtils.getConnection(); Ji1# >;&
conn.setAutoCommit(false); wzmQRn;s
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >I0 a$w
for(int i=0;i<CountCache.list.size();i++){ Jh36NE8r
CountBean cb=(CountBean)CountCache.list.getFirst(); }jP/XO1f
CountCache.list.removeFirst(); GuaF B[4
ps.setInt(1, cb.getCountId()); ({$rb-
ps.executeUpdate();⑴ &os:h]
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//ps.addBatch();⑵ 5|`./+Ghk
} pV!WZUfg
//int [] counts = ps.executeBatch();⑶ (dy:d^
conn.commit(); K@oyvJ$
}catch(Exception e){ }7K~-
e.printStackTrace(); [ \%a7ji#
} finally{ snNB;hkj
try{ qP zxP @4
if(ps!=null) { jK%Lewq
ps.clearParameters(); (dx~lMI
ps.close(); @k# xr
ps=null; kY9$ M8b
} Q ~n%c7
}catch(SQLException e){} 3hEbM'L
DBUtils.closeConnection(conn); KdzV^6K<c
} >wFn|7\)s>
} ]r%fAmj
public long getLast(){ 3qDbfO[
return lastExecuteTime; Ls3r( Tf
} &m]jYvRc
public void run(){ ;?TM_%>
long now = System.currentTimeMillis(); V&/Cb&~Uw
if ((now - lastExecuteTime) > executeSep) { e~9g~k]s
//System.out.print("lastExecuteTime:"+lastExecuteTime); FF7?|V!Q
//System.out.print(" now:"+now+"\n"); |Ho}
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); fQ-IM/z
lastExecuteTime=now; *+00
executeUpdate(); oMYZ^b^
} ixoN#'y<"
else{ 7{k?"NF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); SL\15`[{
} W[e2J&G
} bweAmSs
} 5d# 73)x$
//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 $:UD #eh0?
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类写好了,下面是在JSP中如下调用。 JW=q'ibR
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<% F}@]Lq+
CountBean cb=new CountBean(); ,% .)mf
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v`Ja Bn
CountCache.add(cb); [A]
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out.print(CountCache.list.size()+"<br>"); t1$pl6&,
CountControl c=new CountControl(); jR+kx:+
c.run(); NSR][h_
out.print(CountCache.list.size()+"<br>"); #BgiDLh
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