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: Y6%OV?}v!
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CountBean.java s]8J+8
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/* `0XbV A
* CountData.java V>uW|6
* fX$4TPy(h
* Created on 2007年1月1日, 下午4:44 -qP[$Q
* fQ_8{=<-&X
* To change this template, choose Tools | Options and locate the template under lnSE+YJ>
* the Source Creation and Management node. Right-click the template and choose o4'4H y
* Open. You can then make changes to the template in the Source Editor. aq \TO?
*/ @wgGnb)
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package com.tot.count; >upUY(3&
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/**
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* DSZhl-uGM
* @author AbI*/|sY
*/ 4x?u5L
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public class CountBean { 9.#R?YP$
private String countType; >8;%F<o2
int countId; d4h(F,K7V
/** Creates a new instance of CountData */ )[X!/KR90
public CountBean() {} )bU")
public void setCountType(String countTypes){ )0d".Q|v4
this.countType=countTypes; bK;aV&
} IeI%X\G
public void setCountId(int countIds){ NWwtq&pz2
this.countId=countIds; 0Ilvr]1a4
} 35kbE'
public String getCountType(){ Ul0<Zxv
return countType; UZ3Aq12U}a
} \bA'Furp
public int getCountId(){ d]~1.i
return countId; $<e .]`R
} %vYlu%c<
} Eq;frnw>q
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CountCache.java (Ha}xwA~(
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/* /r@
* CountCache.java YgOgYo{E!
* L=!kDU
* Created on 2007年1月1日, 下午5:01 QGG(I7{-
* pYUkd!K"
* To change this template, choose Tools | Options and locate the template under .+o>
* the Source Creation and Management node. Right-click the template and choose S,v >*AF
* Open. You can then make changes to the template in the Source Editor. 8B+^vF
*/ _H<OfAO
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package com.tot.count; ?o5#Ve$-X
import java.util.*; @@mW+16
/** vUx$[/<
* yzb&
* @author WR EGRy
*/ MJpTr5Vs
public class CountCache { ,,wx197XeD
public static LinkedList list=new LinkedList(); c;}n=7,>:L
/** Creates a new instance of CountCache */ `|?$; )
public CountCache() {} @7 HBXP
public static void add(CountBean cb){ \JC(pn
if(cb!=null){ zn$Ld,
list.add(cb); Jiylrf`o
} 1Klu]J%
} 9sU,.T
} &n kGdHX/a
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CountControl.java H1i4_T
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/* P,=J"%a -
* CountThread.java
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* g7f%(W2dd
* Created on 2007年1月1日, 下午4:57 D|'Z c&
* jt?%03iuk
* To change this template, choose Tools | Options and locate the template under "E!p1
* the Source Creation and Management node. Right-click the template and choose "fd=(&
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* Open. You can then make changes to the template in the Source Editor. ui0(#2'h%
*/ @5GP;3T
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package com.tot.count; 4tNgK[6M
import tot.db.DBUtils; Cms"OkN
import java.sql.*; 8^i,M^f^{
/** S9055`v5
* )X$n'E
* @author =DwH*U/YR
*/ tO3B_zC
public class CountControl{ "z4E|s
private static long lastExecuteTime=0;//上次更新时间 yE{UV>ry
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 4zbV' ]
/** Creates a new instance of CountThread */ io_64K+K
public CountControl() {} b?L43t ,
public synchronized void executeUpdate(){ 9 NSYrIQ"
Connection conn=null; j'cCX[i
PreparedStatement ps=null; \9Zfu4WR
try{ 7O :Gi*MA
conn = DBUtils.getConnection(); A1T;9`E
conn.setAutoCommit(false); S]@iS[|?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .sMi"gg
for(int i=0;i<CountCache.list.size();i++){ ~h|L;E"
CountBean cb=(CountBean)CountCache.list.getFirst();
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CountCache.list.removeFirst(); Yr0i9Qow
ps.setInt(1, cb.getCountId()); I65GUX#DV
ps.executeUpdate();⑴ f\w4F'^tj
//ps.addBatch();⑵ -bQvJ`iF
} H}rP{`m
//int [] counts = ps.executeBatch();⑶ NO1]JpR
conn.commit(); vbJMgdHFR
}catch(Exception e){ h0}-1kVT^
e.printStackTrace(); KJZY.7
} finally{ _fw'c*j
try{ <-7Ha_#
if(ps!=null) { 6
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ps.clearParameters(); 'o9V0#$!
ps.close(); ]2
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ps=null; K2v)"|T)
} K*RRbtb
}catch(SQLException e){} hUc|Xm
DBUtils.closeConnection(conn); ?"Q6;np*
} lph_cY3p
} P~>nlm82]
public long getLast(){ EJY:C9W
return lastExecuteTime; @Q5^Q'!
} q\Z1-sl~s
public void run(){ i/B"d,=<
long now = System.currentTimeMillis(); "E#%x{d
if ((now - lastExecuteTime) > executeSep) { !OemS7{
//System.out.print("lastExecuteTime:"+lastExecuteTime); oWOZ0]H1
//System.out.print(" now:"+now+"\n"); Zwl?*t\D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); tF(mD=[
lastExecuteTime=now; yB[LO(i
executeUpdate(); AP@d2{"m}
} #}?$mxME*
else{ F@3,>~[%I
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); oaE3Aa
} ]P^ +~
} 6Wp:W1E{`
} =wc[r?7
//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 Hq8.O/Y"=
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类写好了,下面是在JSP中如下调用。 x$sQ .aT
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<% ' 'N@ <|
CountBean cb=new CountBean(); j+seJg<_
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )qe o`4+y
CountCache.add(cb); ;rbn/6
out.print(CountCache.list.size()+"<br>"); @,.H)\a4
CountControl c=new CountControl(); dno*Usx5d0
c.run(); ,B><la87
out.print(CountCache.list.size()+"<br>"); |R;=P(0it
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