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: QCOLC2I
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CountBean.java )O3jQ_q=
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/* -Z%F mv8
* CountData.java u7;`4P:o@
* z)lM2x>|*
* Created on 2007年1月1日, 下午4:44 pkX v.D`
* HU &)
* To change this template, choose Tools | Options and locate the template under r6`\d k
* the Source Creation and Management node. Right-click the template and choose m0A# 6=<
* Open. You can then make changes to the template in the Source Editor. i&`!|X-=R
*/ l'U1
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package com.tot.count; akT|Y4KxD
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/** 9ilM@SR
* #{!O,`qD
* @author sVu k
*/ iTh
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public class CountBean { H]s4% 9T
private String countType; W h| L
int countId; 7*i}km
/** Creates a new instance of CountData */ !@u&{"{`
public CountBean() {} Sx8l<X
public void setCountType(String countTypes){ &p5&=zV}
this.countType=countTypes; {j?7d; 'j
} @(-yrU
public void setCountId(int countIds){ +?;j&p
this.countId=countIds; {h#6z>p"u2
} 4O!E|/`wO
public String getCountType(){ F>N+<Z
return countType; t5paYw-b
} R"*R99
public int getCountId(){ 2"@Ft()]
return countId; K;x~&G0=
} lop uf/U0
} B{p4G`$i1
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CountCache.java ibJl;sJ
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/* f=o4I2Y[
* CountCache.java <Nex8fiJ9
* nq'M?c#E
* Created on 2007年1月1日, 下午5:01 R:A'&;S
* I}+;ME|<2
* To change this template, choose Tools | Options and locate the template under $jG4pPG
* the Source Creation and Management node. Right-click the template and choose b3\B8:XFo|
* Open. You can then make changes to the template in the Source Editor. (/K5! qh
*/ D`Gt
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package com.tot.count; =EW3&+Lt
import java.util.*; ?;
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/** 5`~mqqR5
* ?E<c[*F05
* @author V&i2L.{G)
*/ .+yW%~0
public class CountCache { R)+t]}
public static LinkedList list=new LinkedList(); R&#tSL
/** Creates a new instance of CountCache */ /b#q*x-b
public CountCache() {} zDDK
public static void add(CountBean cb){ P16YS8$
if(cb!=null){ BwxnDe G)
list.add(cb); _A 2Lv]vfV
} V^n0GJNo
} JrDHRIkgm
} QU/fT_ORw
E-fr}R}
CountControl.java QHzgy?
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/* DyfsTx
* CountThread.java Mra35
* QU T"z'
* Created on 2007年1月1日, 下午4:57 O*G1 QX
* ]p]UTCo!'
* To change this template, choose Tools | Options and locate the template under Hx
%$X
* the Source Creation and Management node. Right-click the template and choose !>n|c$=;qk
* Open. You can then make changes to the template in the Source Editor. #Fs|f3-@
*/ &[_ZXVva~
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package com.tot.count; & Kmy}q
import tot.db.DBUtils; gn ?YF`
import java.sql.*; J}TfRrf
/** y+U83a[L*
* q[d)e6
* @author y-9+a7j
*/ PKf:O
public class CountControl{ exDkq0u]
private static long lastExecuteTime=0;//上次更新时间 qu~X.pW
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zizk7<?L.
/** Creates a new instance of CountThread */ lY'N4x7n
public CountControl() {} rk|@B{CA;
public synchronized void executeUpdate(){ Zx{96G+1
Connection conn=null; bik*ZC?E
PreparedStatement ps=null; >(3\kiYS
try{ T8XY fcc*h
conn = DBUtils.getConnection(); U
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conn.setAutoCommit(false); 30Drrno7Io
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); dE5D3ze
for(int i=0;i<CountCache.list.size();i++){ >xg5z
CountBean cb=(CountBean)CountCache.list.getFirst(); uzBz}<M=
CountCache.list.removeFirst(); ?j{C*|yHO
ps.setInt(1, cb.getCountId()); OBOwz4<
ps.executeUpdate();⑴ T_;]fPajjD
//ps.addBatch();⑵ DlTR|(AL
} w?LrJ37u
//int [] counts = ps.executeBatch();⑶ *:hyY!x
conn.commit(); mfom=-q3k
}catch(Exception e){ Dl C@fZD
e.printStackTrace(); ".U^ifF
} finally{ riCV&0"n
try{ WE6\dhJ<
if(ps!=null) { }Ln@R~[
ps.clearParameters(); ,gx)w^WTm
ps.close(); 3[IJhR[
ps=null; #0"~G][#
} vF4]ux&
}catch(SQLException e){} |L::bx(
DBUtils.closeConnection(conn); #X`8dnQZ
} K84^Oq
} ^G|98yc!'
public long getLast(){ xT*d/Oa w
return lastExecuteTime; jz'<
} 6bO~/mpWT~
public void run(){ {Wv%zA*8
long now = System.currentTimeMillis(); >v+jh(^
if ((now - lastExecuteTime) > executeSep) { Y`GOER
//System.out.print("lastExecuteTime:"+lastExecuteTime); d=3'?l`
//System.out.print(" now:"+now+"\n"); _yH`t[
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }-DE`c
lastExecuteTime=now; izZ=d5+K
executeUpdate(); 06mlj6hV
} 4Ysb5m)u
else{ 3x@<Z68S
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); )9v`f9X){
} `BY&>WY[
} uQqWew8l+
} Pbu{'y3J
//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 v?:: |{
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类写好了,下面是在JSP中如下调用。 9X}I>
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<% OJO!FH)
CountBean cb=new CountBean(); SOf{Hx0C6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); GK*v{`
CountCache.add(cb); ZcE_f>KV
out.print(CountCache.list.size()+"<br>"); Vb|#MNf)
CountControl c=new CountControl(); ZC0-wr\
c.run(); g"_C,XN
out.print(CountCache.list.size()+"<br>"); <skajQQ
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