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: .eo~?u<j&
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CountBean.java 5C/2b.-[
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/* )!e3.C|V1W
* CountData.java 4r\*@rq
* 6mCq/$
* Created on 2007年1月1日, 下午4:44 id^|\hDR
* 1Ao6y.S
* To change this template, choose Tools | Options and locate the template under 1?(cmXj
* the Source Creation and Management node. Right-click the template and choose 2{-!E ^g
* Open. You can then make changes to the template in the Source Editor. |QVr`tE<
*/ _#!U"hkH
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package com.tot.count; /s:w^g~
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/** O~ 27/
* H?tUCbw
* @author w?*z^y@
*/ /v|Onq1Y4
public class CountBean { n!G.At'JP
private String countType; @RGDhwS47
int countId; 5;mRGY
/** Creates a new instance of CountData */ =q+R
public CountBean() {} T~Ly^|Ihz
public void setCountType(String countTypes){ p&^J=_O
this.countType=countTypes; BC! 6O/kr
} U\jb"
public void setCountId(int countIds){ t<63 8`{kk
this.countId=countIds; ZIpD{ >/
} H z@h0+h
public String getCountType(){ :"QfF@Z{
return countType; *0y{ ~@
} zrRFn `B
public int getCountId(){ ZyI$M 3{J
return countId; I{ ryD -!
} &nY;=Hv`WY
} #DFp[\)1
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CountCache.java uSN"vpc4D
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/* E]I$}>k
* CountCache.java M;jcUX_{
* E{y1S\7K
* Created on 2007年1月1日, 下午5:01 5\hd4
* h2~4G)J
* To change this template, choose Tools | Options and locate the template under W:`#% :C
* the Source Creation and Management node. Right-click the template and choose RWKH%C[Yd
* Open. You can then make changes to the template in the Source Editor. BRS#Fl:
*/ ~#PLAP3-
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package com.tot.count; T2FE+ A]n9
import java.util.*; $t}<85YCQ
/** +=BAslk
* t"vRc4mf
* @author )Si2u5
*/ SA;#aj}rV
public class CountCache { D`yEwpV^
public static LinkedList list=new LinkedList(); iW%8/$
/** Creates a new instance of CountCache */ !H@0MQ7
public CountCache() {} 7Nzbz3
public static void add(CountBean cb){ z>m=h)9d~
if(cb!=null){ !do?~$Og
list.add(cb); !w39FfU{
} :A1:
} j%IF2p2
} T,%j\0
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CountControl.java "IQ/LbOqm_
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/* ntVS:F
* CountThread.java KNLnn;l
* P"/G
* Created on 2007年1月1日, 下午4:57 $za8"T*I
* *Hz^K0:8(
* To change this template, choose Tools | Options and locate the template under '' O 7=\
* the Source Creation and Management node. Right-click the template and choose <h-vjz
* Open. You can then make changes to the template in the Source Editor. t. ='/`!N
*/ T .FI'wy
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package com.tot.count; BZ54*\t
import tot.db.DBUtils; EJ@p-}I!
import java.sql.*; hrG M|_BE
/** :a
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* 4%nE*H%
* @author Eow_WW;P
*/ y*pUlts<
public class CountControl{ !$-\;<bZw
private static long lastExecuteTime=0;//上次更新时间 fk1ASV<rN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 CCBfKp
/** Creates a new instance of CountThread */ InXn%9]p]
public CountControl() {} Szbb_i{_
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public synchronized void executeUpdate(){ ,(8;y=wux
Connection conn=null; WmY``
PreparedStatement ps=null; (bsXo
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try{ pn.wud}R
conn = DBUtils.getConnection(); &e6CJ
conn.setAutoCommit(false); ])xx<5Jt4
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); h 3]wL.V
for(int i=0;i<CountCache.list.size();i++){ 79`AM
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CountBean cb=(CountBean)CountCache.list.getFirst(); R"
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CountCache.list.removeFirst(); QFYWA1<pDh
ps.setInt(1, cb.getCountId()); 0"CG7Vg,zh
ps.executeUpdate();⑴ B2-V@06
//ps.addBatch();⑵ 28 8XF9B^
} o.0ci+z@
//int [] counts = ps.executeBatch();⑶ |B?27PD
conn.commit(); *h}XWB C1q
}catch(Exception e){ \"X!2
e.printStackTrace(); E_vq
} finally{ kS bu]AB
try{ n4}Br;%
if(ps!=null) { ^h69Kr#d4
ps.clearParameters(); 0g0i4IV
ps.close(); xuqv6b.
ps=null; $0vb^
} u(fm@+$^
}catch(SQLException e){} |&RU/ a
DBUtils.closeConnection(conn); &*+'>UEe5
} :A/d to
} z^'gx@YD*v
public long getLast(){ /Mvf8v
return lastExecuteTime; L*YynF
} ;M)QwF1
public void run(){ 3j\1S1
long now = System.currentTimeMillis(); KET2Ws[w
if ((now - lastExecuteTime) > executeSep) { |S_eDjF
//System.out.print("lastExecuteTime:"+lastExecuteTime); U4d:] z
//System.out.print(" now:"+now+"\n"); 6}d.5^7lr
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ZrsBm_Rx
lastExecuteTime=now; !@}wDt
executeUpdate(); uG,5BV .M
} |y(Q
else{ &5yVxL:
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); P)P*Xqr#:
} lhy*h_>
} #d6)#:uss
} %nf6%@s
//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 5>[u `
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类写好了,下面是在JSP中如下调用。 h1de[q)
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<% .(K)?r-g5
CountBean cb=new CountBean(); o~`/_+
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )Y"+,$$>Y`
CountCache.add(cb); VK m&iidU
out.print(CountCache.list.size()+"<br>"); pR=@S>!|
CountControl c=new CountControl(); h`^jyoF"(
c.run(); ,o86}6Ag
out.print(CountCache.list.size()+"<br>"); k\5c|Wq|g
%>