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: \QK@wgu
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CountBean.java BUBx}dbCM
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/* $5&%X'jk
* CountData.java {\[ Gl
* \tI%[g1M
* Created on 2007年1月1日, 下午4:44 R#d~a;j
* {]R'U/
* 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 nTqU~'d'
* Open. You can then make changes to the template in the Source Editor. CjQO5
*/ [b3!H{b#
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package com.tot.count; MuY:(zC%
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/** ^ F]hW
* )r9 9zdUk
* @author !uEEuD#
*/ d+JK")$9C
public class CountBean { l'+3
6
private String countType; 'cs(gc0
int countId; YO7U}6wBt
/** Creates a new instance of CountData */ Lj1l]OD
public CountBean() {} ;?2)[a
public void setCountType(String countTypes){ cJ96{+
this.countType=countTypes; ,&t+D-s<f
} !!1?2ine
public void setCountId(int countIds){ dE7x
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this.countId=countIds; "<ZV'z
} YP2VSK2Q
public String getCountType(){ C Bkoky9&
return countType; c|Ivet>3
} nj[TTndJt
public int getCountId(){ `>:5[Y
return countId; .{1$;K @
} H`JFXMa<
} U6]#RxH
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CountCache.java .Mq#88o.*
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/* 4mX(.6
* CountCache.java x>#{C,Fi
* W>@ti9\t
* Created on 2007年1月1日, 下午5:01 jdxHWkQ
* TrjyU
* To change this template, choose Tools | Options and locate the template under Lzh8-d=HQ
* the Source Creation and Management node. Right-click the template and choose xE1?)
* Open. You can then make changes to the template in the Source Editor. bwsKdh
*/ uk):z$x
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package com.tot.count; +MoUh'/u
import java.util.*; <|Td0|x
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/** cI=6zMB
* [RyVR
* @author ;.>*O
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*/ Cy~ IB [
public class CountCache { B]rdgjz*
public static LinkedList list=new LinkedList(); s.2f'i+
/** Creates a new instance of CountCache */ 2@|`Ugjptl
public CountCache() {} ?XBdBR_"^
public static void add(CountBean cb){ eHphM;C
if(cb!=null){ pHeG{<^
list.add(cb); F5o8@ Ib]:
} =L!&Z
} U%q)T61
} KYFKH+d>m
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CountControl.java k%.v`H!
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/* F\:~^`
* CountThread.java |a(KVo
* LE\*33k_
* Created on 2007年1月1日, 下午4:57 (Z),gxt
* V*p[6{U0
* To change this template, choose Tools | Options and locate the template under n ay\)
* the Source Creation and Management node. Right-click the template and choose h,{m{Xh
* Open. You can then make changes to the template in the Source Editor. RHF"$6EAFG
*/ uJ% <+I
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package com.tot.count; 22l'kvo4"
import tot.db.DBUtils; !dqC6a
import java.sql.*; x5lVb$!G
/** Fy=GU<&AI
* 3q]0gU&??
* @author VE\L&d2S
*/ ^{Y, `F
public class CountControl{ eD>b|U=/
private static long lastExecuteTime=0;//上次更新时间 o0H^J,6gV
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 `Y&`2WZ ~
/** Creates a new instance of CountThread */ $S6(V}yh
public CountControl() {} ?%O>]s
public synchronized void executeUpdate(){ km%r{
Connection conn=null; >F$9&s&
PreparedStatement ps=null; pzF_g-B
try{ T\6Qr$t
conn = DBUtils.getConnection(); 2I.FSR_G?
conn.setAutoCommit(false); y1V}c,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); !sT>]e
for(int i=0;i<CountCache.list.size();i++){
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CountBean cb=(CountBean)CountCache.list.getFirst(); a5a
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CountCache.list.removeFirst(); r:QLU]
ps.setInt(1, cb.getCountId()); ;z:Rj}l
ps.executeUpdate();⑴ _J,**AZ~z
//ps.addBatch();⑵ uo:RNokjJ
} V.~kG ,Ht
//int [] counts = ps.executeBatch();⑶ /J`}o}
conn.commit(); mv9D{_,pD
}catch(Exception e){ ,ri&zbB
e.printStackTrace(); RD`|Z~:q:K
} finally{ MK#
try{ /X}1%p
if(ps!=null) { gwj?.7N*k
ps.clearParameters(); x\yM|WGL
ps.close(); }QE.|.fA1
ps=null; ;}B=g/C
} m$8siF{<q
}catch(SQLException e){} #qd!_oN
DBUtils.closeConnection(conn); JsY,Q,D q
} Ws2q/[\oz
} m#+0m!
public long getLast(){ 7[Us.V@
return lastExecuteTime; 6i/unwe!`)
} bb_elmb)n
public void run(){ [v1$Lp
long now = System.currentTimeMillis(); z~H1f$}
if ((now - lastExecuteTime) > executeSep) { 5hE#y]pfN
//System.out.print("lastExecuteTime:"+lastExecuteTime); X9*n[ev
//System.out.print(" now:"+now+"\n"); _S_,rTf&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 4MC]s~n
lastExecuteTime=now; 6~dAK3v5
executeUpdate(); O"\4[HE^
} ?q!4 REM
else{ Ar%*NxX
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); M6-uTmN:d
} $QiMA,
} dsIbr"m
} eF3NyL(A
//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 ?V`-z#y7
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类写好了,下面是在JSP中如下调用。 U&3!=|j
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<% uQdeKp4(
CountBean cb=new CountBean(); 7w73,r/D8A
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); e1[ReZW
CountCache.add(cb); -Mo4`bN
out.print(CountCache.list.size()+"<br>"); c&;" Y{
CountControl c=new CountControl(); 8GkWo8rPk
c.run(); k}LIMkEa4a
out.print(CountCache.list.size()+"<br>"); /KH85/s
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