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: N?"]
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CountBean.java _a T5jR=
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/* Y0-n\|
* CountData.java @I!0-OjL
* *!7O~yQ
* Created on 2007年1月1日, 下午4:44 d-dEQKI?;
* N<injx
* To change this template, choose Tools | Options and locate the template under e**qF=HCw
* the Source Creation and Management node. Right-click the template and choose \P`hq^;
* Open. You can then make changes to the template in the Source Editor. >\3V a
*/ &KRX[2
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package com.tot.count; j8lb~0JD
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/** "1M[5\Ax
* jtc]>]6i
* @author NHZz _a=
*/ 9mTJ|sN:e
public class CountBean { JnM["Q=`
private String countType; '(|ofJe!
int countId; _zi|
/** Creates a new instance of CountData */ WEi2=3dV
public CountBean() {} SNI)9k(T{
public void setCountType(String countTypes){ Hja3a{LH
this.countType=countTypes; nc|p )
} G*P#]eO
public void setCountId(int countIds){ X_\otVh(D
this.countId=countIds; '16b2n+F@#
} V[Ui/M!9Z
public String getCountType(){ ,1o FPa{?
return countType; OYTkV}tG
} %Y*Ndt 4
public int getCountId(){
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return countId; JrRH\+4K
} @i IRmQ
} Dwfu.ZJa
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CountCache.java YglmX"fLf
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/* J{fH['tzO
* CountCache.java RdRp.pb8
* I(BQ34q
* Created on 2007年1月1日, 下午5:01 <l E<f+
* ]|PiF+
* To change this template, choose Tools | Options and locate the template under _^%,x
* the Source Creation and Management node. Right-click the template and choose n]o<S+z
* Open. You can then make changes to the template in the Source Editor. vT,AMja
*/ 3m!X/u
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package com.tot.count; )
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import java.util.*; Fyatd
/** sN01rtB(UT
* 6zuTQ^pz
* @author H*'IK'O
*/ mSl.mi(JiZ
public class CountCache { mb^~qeRQ
public static LinkedList list=new LinkedList(); |imM#wF
/** Creates a new instance of CountCache */ hy"\RW
public CountCache() {} }*pi<s
public static void add(CountBean cb){ <k'h:KB?`
if(cb!=null){ 1ztG;\
list.add(cb); :(*V?WI
} K:#I
} jkF^-Up.
} =R$u[~Xl2X
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CountControl.java -Cc^d!::
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/* Ig0VW)@
* CountThread.java _H7x9
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* 5IjGm
* Created on 2007年1月1日, 下午4:57 |~mOfuQb
* ^'{Fh"5
* To change this template, choose Tools | Options and locate the template under ]Wlco
* the Source Creation and Management node. Right-click the template and choose p}pjfG
* Open. You can then make changes to the template in the Source Editor. eF-."1
*/ !9VY|&fHe
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package com.tot.count; 7CURhDdk
import tot.db.DBUtils; C{xaENp
import java.sql.*; ^EQ<SCh
/** F8,RXlGfA[
* ,G?WAOy,
* @author lE(HFal0-(
*/ tpQ(g%
public class CountControl{ YWO)HsjP
private static long lastExecuteTime=0;//上次更新时间 bI9~jWgGp
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TpwkD_fg
/** Creates a new instance of CountThread */ Zaf:fsj>
public CountControl() {} jZkcBIK2
public synchronized void executeUpdate(){ FxWS V| Z
Connection conn=null; ?_9
PreparedStatement ps=null; LxSpctiNx
try{ >7T'OC
conn = DBUtils.getConnection(); 6Vnsi%{
conn.setAutoCommit(false); Nkth>7*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W/bQd)Jvk
for(int i=0;i<CountCache.list.size();i++){ Ee%%d
CountBean cb=(CountBean)CountCache.list.getFirst(); Q6!zZ))~
CountCache.list.removeFirst(); qvKG-|j
ps.setInt(1, cb.getCountId()); z3m85F%dR
ps.executeUpdate();⑴ WUXx;9 >
//ps.addBatch();⑵ u$Jz~:=,
} )e=D(qd
//int [] counts = ps.executeBatch();⑶ +`3)o PV)
conn.commit(); ' ;FnIZ
}catch(Exception e){ |tMWCA
e.printStackTrace(); Kaqc74Mv
} finally{ Vl=l?A8
try{ a;qryUyG
if(ps!=null) { bP$dU,@p~
ps.clearParameters(); e>7>j@(K]
ps.close(); SaAFz&WRl
ps=null; Q}K"24`=
} s %``H`
}catch(SQLException e){} M@H;pJ+B
DBUtils.closeConnection(conn); 4ber!rJM
} *:LK8U
} x$.^"l-vX
public long getLast(){ g<;q.ZylT
return lastExecuteTime; ?*1uN=oI{*
} o!Ieb
public void run(){ w3obIJm
long now = System.currentTimeMillis(); g._]8{K
if ((now - lastExecuteTime) > executeSep) { v,{
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//System.out.print("lastExecuteTime:"+lastExecuteTime); :vqgGKml$
//System.out.print(" now:"+now+"\n"); bL+_j}{:N
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); f<fXsSv(
lastExecuteTime=now; }1c|gQ
executeUpdate(); PI:4m%[
} e L^|v
else{ p6]1w]*R
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 4I
k{
} )@l%
} BB!THj69a6
} j<99FW"@e
//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 fo#fg8zX%
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类写好了,下面是在JSP中如下调用。 2Aazy'/
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<% p{Yv3dNl
CountBean cb=new CountBean(); F^t DL:
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); wc NOLUl
CountCache.add(cb); HJLG=mU
out.print(CountCache.list.size()+"<br>"); G )trG9 .a
CountControl c=new CountControl(); gx8ouOh
c.run(); k"T}2 7
out.print(CountCache.list.size()+"<br>"); $m%fwB
%>