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: D~Rv"Hh
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CountBean.java +~n"@ /
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/* r?%,#1|$$
* CountData.java rds4eUxe
* 4R}$P1 E
* Created on 2007年1月1日, 下午4:44 `Lj'2LoER
* E51'TT9
* To change this template, choose Tools | Options and locate the template under ;659E_y>
* the Source Creation and Management node. Right-click the template and choose hd>_K*oH
* Open. You can then make changes to the template in the Source Editor. /A82~
*/ WF_24Mw
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package com.tot.count; Q=u [j|0mc
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/** AMe_D
* jJ7 "9
* @author SdXAL
*/ Ue&I]/?;$
public class CountBean { 0c
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private String countType; EUmbNV0u
int countId; -~NjZ=vPh
/** Creates a new instance of CountData */ j
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public CountBean() {} 3kW%,d*_
public void setCountType(String countTypes){ (nnIRN<}$
this.countType=countTypes; /4>|6l=
} yD yMI
public void setCountId(int countIds){ ' JAcN@q~z
this.countId=countIds; 4<btWbk5u*
} tGwQUn
public String getCountType(){ OI)U c .
return countType; 1SG^g*mf
} zbZN-j#
public int getCountId(){ g0M/Sv
return countId; V8947h|&
} ,e@707d`\
} v$~ZT_"(9
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CountCache.java *@E&O^%cO
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/* >>.4@
* CountCache.java k/m-jm_h
* _zG[b/:p
* Created on 2007年1月1日, 下午5:01 {1}p+dEK
* =
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* To change this template, choose Tools | Options and locate the template under |bX{MF
* the Source Creation and Management node. Right-click the template and choose F3=iyiz6
* Open. You can then make changes to the template in the Source Editor. ? oQ_qleuo
*/ Y;1J`oT
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package com.tot.count; w=x
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import java.util.*; evE$$# 6R
/** D.,~I^W
* 115zvW
* @author :^ J'_
*/ l~#%j( Yo
public class CountCache { '-[?iF@l
public static LinkedList list=new LinkedList(); t}fU 2Yb
/** Creates a new instance of CountCache */ G|LcTV
public CountCache() {} E>&oe&`o'
public static void add(CountBean cb){ en8l:INX
if(cb!=null){ AkX8v66:
list.add(cb); NGAjajB
} osPrr QoH
} :rnj>U6<>
} s}Q*zy
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CountControl.java TIVrbO\!o
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/* %)}y[
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* CountThread.java pVC;''E
* ~IS3i'bh
* Created on 2007年1月1日, 下午4:57 ;hkzL_' E)
* !3Ed0h]Bfa
* To change this template, choose Tools | Options and locate the template under 8gXf4A(N
* the Source Creation and Management node. Right-click the template and choose ~Aoo\fN_U
* Open. You can then make changes to the template in the Source Editor. e)kVS}e?
*/ vFH1hm
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package com.tot.count; Qe4"a*l-r
import tot.db.DBUtils; "a]Ff&T-
import java.sql.*; f1RX`rXf
/** JAS!eF
* ;2Za]%'
* @author *v0}S5^/"
*/ 89l{h8R
public class CountControl{ T]y^PT<8?
private static long lastExecuteTime=0;//上次更新时间 -n]E\"
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Y5\=5r/
/** Creates a new instance of CountThread */ &BkdC,o
public CountControl() {} gB}UzEj^<
public synchronized void executeUpdate(){ $LJCup,1"
Connection conn=null; b:YyzOqEu
PreparedStatement ps=null; MzCZj
try{ vF.Ml
conn = DBUtils.getConnection();
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conn.setAutoCommit(false); #]e](j>]
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;`}b
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for(int i=0;i<CountCache.list.size();i++){ 0|OmQ\SQ
CountBean cb=(CountBean)CountCache.list.getFirst(); _?~)B\@~0
CountCache.list.removeFirst(); >o8N@`@VK-
ps.setInt(1, cb.getCountId()); FW,@.CX
ps.executeUpdate();⑴ t.6gyrV7><
//ps.addBatch();⑵ N-<m/RS
} 3PRK.vf
//int [] counts = ps.executeBatch();⑶ x
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conn.commit(); I;3Uzv
}catch(Exception e){ [LrA_N
e.printStackTrace(); L7 g4'
} finally{ U=>4=gsG
try{ Z*M-PaU}
if(ps!=null) { sI#r3:?i
ps.clearParameters(); 8~eYN-#W&
ps.close(); I+FQ2\J*H
ps=null; <:Z-zQp)?
} MP%pEUomev
}catch(SQLException e){} 07qL@![!
DBUtils.closeConnection(conn); W6L}T,epX
} [y1
x`WOk9
} N83g=[
public long getLast(){ JN<IMH
return lastExecuteTime; "M4gl
} Ilv
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public void run(){
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long now = System.currentTimeMillis(); &Ez]pKjB
if ((now - lastExecuteTime) > executeSep) { D$PR<>=y
//System.out.print("lastExecuteTime:"+lastExecuteTime); 8VLD yX2-
//System.out.print(" now:"+now+"\n"); .80L>0
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 7) e#b
lastExecuteTime=now; rulw6vTB(
executeUpdate(); (Gpk;DD
} t9+ME|
else{ rhvTV(Bz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _)F0oC {
} 4&/m>%r
} EE[JXoke
} /{+77{#Qn
//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 nN[gAM (
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类写好了,下面是在JSP中如下调用。 3FpS o+
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<% BHEZ<K[U
CountBean cb=new CountBean(); o7WK"E!pF'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); k=r)kkO)
CountCache.add(cb); Fmux#}Z
out.print(CountCache.list.size()+"<br>"); m-)yQM8
CountControl c=new CountControl(); *w_f-YoXp
c.run(); O a#m}b
out.print(CountCache.list.size()+"<br>"); Mg}8 3kS
%>