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: C8.MoFfhe
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CountBean.java {H%1sI
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/* ~b.e9FhdA
* CountData.java S4BU !
* Nb@zn0A(;
* Created on 2007年1月1日, 下午4:44 %QrpFE5V5
* au 5qbP
* To change this template, choose Tools | Options and locate the template under 9q!./)
* the Source Creation and Management node. Right-click the template and choose xBi``x2eY
* Open. You can then make changes to the template in the Source Editor. ]pP [0S
*/ 9 ~$'?
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package com.tot.count; )s4a<Sc]
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/** seo.1.Da2
* %t\~3pw=
* @author )YP9
*/ )$e_CJ}9e
public class CountBean { Ykd< }KE>
private String countType; LdM9k(
int countId; B7!dp`rPp
/** Creates a new instance of CountData */ T.p:`}Ma
public CountBean() {} l TRQ/B
public void setCountType(String countTypes){ Zm!5X9^!
this.countType=countTypes; csay\Q{
} byUstm6y
public void setCountId(int countIds){ B)4>:j:{?W
this.countId=countIds; VaRP+J}UA.
} N/&t)7
public String getCountType(){ Zl+Ba
return countType; {Jj
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} G(1y_t
public int getCountId(){ |SF5'\d'
return countId; dLnMd0
} 9!sR}
} O}IRM|r"
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CountCache.java Lk~aMbw#
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/* >'X[*:Cx
* CountCache.java oCftI':@
* I2PFJXp_]n
* Created on 2007年1月1日, 下午5:01 S*-/#j
* Gv3AJ'NL
* To change this template, choose Tools | Options and locate the template under +kK6G#c
* the Source Creation and Management node. Right-click the template and choose A(Ss:7({
* Open. You can then make changes to the template in the Source Editor. I6E!$}
*/ !DUC#)F
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package com.tot.count; z;VabOr^
import java.util.*; oj1,DU
/** P@z,[,sy"$
* ]TmxCTVL
* @author !:^lTvYWZH
*/ e):rr*
public class CountCache { }}'0r2S
public static LinkedList list=new LinkedList(); V]$Tbxg
/** Creates a new instance of CountCache */ (NBq!;_2,x
public CountCache() {} nwm1YPs%v]
public static void add(CountBean cb){ (n,!v)
if(cb!=null){ fudIUG.
list.add(cb); PV_q=70%T
} w_hGWpm
} oG_-a(N
} Y([YDn
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CountControl.java pjP
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/* &m>sGCZ
* CountThread.java 3 O)^Hq+9
* c)tG1|Og]
* Created on 2007年1月1日, 下午4:57 voHFU#Z$
* WTcrfs)T
* To change this template, choose Tools | Options and locate the template under Cd"iaiTD0
* the Source Creation and Management node. Right-click the template and choose Zh]FL8[
nc
* Open. You can then make changes to the template in the Source Editor. g}B|ZRz+{
*/ @m=xCg.Z
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package com.tot.count; _26<}&]b*
import tot.db.DBUtils; =R
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import java.sql.*; fv",4L
/** c=}#8d.
* 4/Yk;X[jk
* @author 5fdB<& 9
*/ eBmBD"$
public class CountControl{ j}CZ*
private static long lastExecuteTime=0;//上次更新时间 G-)Q*p{i|
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 */ o=1M<dL
public CountControl() {} 6?3f+=e"~!
public synchronized void executeUpdate(){ =V@5W[bV
Connection conn=null; ~j`;$o
PreparedStatement ps=null; A #y,B
try{ ;L gxL
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conn = DBUtils.getConnection(); [Ie;Jd>gG
conn.setAutoCommit(false); J}9 I5O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); DhAQ|SdCf
for(int i=0;i<CountCache.list.size();i++){ K; +w'/{
CountBean cb=(CountBean)CountCache.list.getFirst(); 6jKZ.S+s)
CountCache.list.removeFirst(); |Ts|>"F'
ps.setInt(1, cb.getCountId()); {iI"Lt
ps.executeUpdate();⑴ X7*i-v@
//ps.addBatch();⑵ VqeK~,}
} H7xyK
//int [] counts = ps.executeBatch();⑶ $#k 8xb
conn.commit(); /8(\AuDT
}catch(Exception e){ QyGTm"9l
e.printStackTrace(); &C.{7ZNt
} finally{ 8~=<!(M)m/
try{ H40~i=.
if(ps!=null) { 7( &\)qf=n
ps.clearParameters(); 5VU
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ps.close(); E8Jy!8/X9T
ps=null; \C
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} ?4kM5NtP
}catch(SQLException e){} t@`w}o[#
DBUtils.closeConnection(conn); _i=431Z40
} DaV:Slp9
} W]]@pbG"H\
public long getLast(){ oM&}akPE
return lastExecuteTime; BJ0P1vh6M
} !5hNG('f
public void run(){ \Tc<27-
long now = System.currentTimeMillis(); R<J1bH1n3
if ((now - lastExecuteTime) > executeSep) { _7h:NLd
//System.out.print("lastExecuteTime:"+lastExecuteTime); g8JO/s5xV
//System.out.print(" now:"+now+"\n"); 7Z#r9Vr
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3q!hY
lastExecuteTime=now; ID-Y*
executeUpdate(); J\kGD
} \lJCBb+k
else{ w&vZ$n-|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); mM> L0
} 5@Y rtZI
} dOm@cs
} +ld]P}
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 yBJf'-K
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类写好了,下面是在JSP中如下调用。 ]Kutuf$t
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<% 4@b~)av)
CountBean cb=new CountBean(); y h
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); (Q_J{[F
CountCache.add(cb); ;
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out.print(CountCache.list.size()+"<br>"); K/Q%tr1W0
CountControl c=new CountControl(); UP18?uM
c.run(); T\(w}
out.print(CountCache.list.size()+"<br>"); H%L oI)w
%>