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: !}>eo2$r^
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CountBean.java xi680'
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/* |x &Z~y
* CountData.java 2X|CuL{]
* }FPM-M3y
* Created on 2007年1月1日, 下午4:44 8#+`9GI
* +w "XNl
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose 7w "sJ
* Open. You can then make changes to the template in the Source Editor. 1^aykrnQ>
*/ >9-Dd)<
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package com.tot.count; fd4;mc1T
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/** U?8i'5)
* mT96]V\
* @author 8NnhT E
*/ #hIEEkCp +
public class CountBean { @. "q
private String countType; ~6p5H}'H1
int countId; __8&Jv\
/** Creates a new instance of CountData */ z4CJn[m9
public CountBean() {} $zdd=.!KiK
public void setCountType(String countTypes){ z~F37]W3[
this.countType=countTypes; _zdNLwE[
} dIma{uv
public void setCountId(int countIds){ s~L`53A
this.countId=countIds; Q-[3j
} rB,ldy,f
public String getCountType(){ d>UnJ)V}
return countType; 8+9\7*
} Tj=gRQ2v
public int getCountId(){ ]* 0(-@
return countId; vyE{WkZxR
}
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} =tq1ogE
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CountCache.java i&JpM]N
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/* Wu ,S\!
* CountCache.java Q |%-9^
* 6;gLwOeOHY
* Created on 2007年1月1日, 下午5:01 EOhC6>ATh
* w^ 3|(F
* To change this template, choose Tools | Options and locate the template under sJOV2#r
* the Source Creation and Management node. Right-click the template and choose mB~~_]M
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* Open. You can then make changes to the template in the Source Editor. )#a7'Ba
*/ n,CD
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package com.tot.count; >Co)2d]
import java.util.*; s'TY[
/** <KX&zi<L)
* +>!V]S
* @author J smB^
*/ =5?.'XMk
public class CountCache { uxb:^d?D!
public static LinkedList list=new LinkedList(); _B3zRO
/** Creates a new instance of CountCache */ U9
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public CountCache() {} `kFiH*5 %z
public static void add(CountBean cb){ 2L:$aZ
if(cb!=null){ KU]ok '
list.add(cb); 4^[
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} BKay*!'PX
} W!91tzs:
} ET. dI.R8
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CountControl.java B)M&\:
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/* TdFT];:
* CountThread.java !>3LGu,
* U7h(-dV
* Created on 2007年1月1日, 下午4:57 Plfdr~$
* |4fF T `
* To change this template, choose Tools | Options and locate the template under ~>g+2]Bn>$
* the Source Creation and Management node. Right-click the template and choose i $C-)d]
* Open. You can then make changes to the template in the Source Editor. $Asr`Q1i
*/ WI&lj<*
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package com.tot.count; LTXz$Z]
import tot.db.DBUtils; R!6=7
import java.sql.*; ^s-25 6iI
/** G>K@AW#
* aClA{
* @author nxfoWy
*/ Bd#
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public class CountControl{ "(f`U.
private static long lastExecuteTime=0;//上次更新时间 I ]9C_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒
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/** Creates a new instance of CountThread */ /8c&Axuv
public CountControl() {}
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public synchronized void executeUpdate(){ QIK
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Connection conn=null; )+EN$*H
PreparedStatement ps=null; :G=FiC
try{
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conn = DBUtils.getConnection(); ]C!?HQ{bsf
conn.setAutoCommit(false); I 8zG~L%"
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); /iG7MC\`
for(int i=0;i<CountCache.list.size();i++){ }`_(<H
CountBean cb=(CountBean)CountCache.list.getFirst(); cG_Vc[
CountCache.list.removeFirst(); fd 1C{^c
ps.setInt(1, cb.getCountId()); e.8$ga{
ps.executeUpdate();⑴ {v,)G)obWw
//ps.addBatch();⑵ |<c
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} 24B<[lSK
//int [] counts = ps.executeBatch();⑶ %u!b& 5]e
conn.commit(); `q_<Im%I
}catch(Exception e){ suVmg-d
e.printStackTrace(); |]sx+NlNc
} finally{ /{*$JF
try{ pj8azFZ
if(ps!=null) { fYX<d%?7
ps.clearParameters(); ppN} k)m
ps.close(); ej^3YNh&
ps=null; Z
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} Ia4)uV8
}catch(SQLException e){} z 7T0u.4Ss
DBUtils.closeConnection(conn); ea9oakF
} (CE7j<j
} '*T]fND4
public long getLast(){ goZ V.,w
return lastExecuteTime; (kw5>c7
} ."6[:MF
public void run(){ @Rq}nq=k
long now = System.currentTimeMillis(); nc?B6IV
if ((now - lastExecuteTime) > executeSep) { qLK?%?.N<
//System.out.print("lastExecuteTime:"+lastExecuteTime); s\3q!A?S3
//System.out.print(" now:"+now+"\n"); i$uN4tVKT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ]Kh2;>=
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lastExecuteTime=now; fZ{[]dn[
executeUpdate(); (S/F)?
} N#k61x
else{ ^%<pJMgdF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ^jSsa
} 8@\7&C(g17
} [hh/1[
} vHKlLl>*2
//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 bS!\#f%9"
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类写好了,下面是在JSP中如下调用。 K$[$4 dX]
#R&H&1
<% >n*\ bXf
CountBean cb=new CountBean(); ^@6q
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); E"PcrWB&
CountCache.add(cb); i$^ZTb^
out.print(CountCache.list.size()+"<br>"); q|(W-h+
CountControl c=new CountControl(); (6gK4__}]
c.run(); WO*9+\[v
out.print(CountCache.list.size()+"<br>"); #x@ eDnb_
%>