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: iMRwp+$
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CountBean.java i<g-+ Qs
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/* *bpD`s
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* CountData.java sds"%]rg
* H~z`]5CN
* Created on 2007年1月1日, 下午4:44 X+]G-
* B@
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* To change this template, choose Tools | Options and locate the template under 1D!<'`)AY
* the Source Creation and Management node. Right-click the template and choose )IZ~G\Ra'
* Open. You can then make changes to the template in the Source Editor. 0NX,QD
*/ ?p8_AL'RS
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package com.tot.count; r^ ZEImjc
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/** x`)&J
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* EI^C{$Y
* @author OJy#w{4
*/ W-lN>]5}m
public class CountBean { (7=9++uU
private String countType; Aj]V`B:65
int countId; Jo23P.#<
/** Creates a new instance of CountData */ gCY';\f!
public CountBean() {} RhLVg~x
public void setCountType(String countTypes){ /%A*aGyIc
this.countType=countTypes; U}j0D2
} qPfQy
public void setCountId(int countIds){ a-L;*
this.countId=countIds; _b;{_g
} AbmAKA@
public String getCountType(){ OX\F~+
return countType; 001FmiV
} tT?cBg{
public int getCountId(){ yd`mG{Z
return countId;
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} oIj#>1~c%
} S\!ana])
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CountCache.java gQ1;],_
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/* HEc+;O1<
* CountCache.java i9][N5\$
* q;>7*Y&
* Created on 2007年1月1日, 下午5:01 Z^MNf
* W#WV fr
* To change this template, choose Tools | Options and locate the template under ><HE;cVg?
* the Source Creation and Management node. Right-click the template and choose aM0f/"-_
* Open. You can then make changes to the template in the Source Editor. WWHoi{q
*/ _8UDT^?8,
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package com.tot.count; 9.B
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import java.util.*; gn".u!9j
/** FZE"7ec>m
* Y,t={HiclX
* @author ;)^`3`
*/ _?0}<kQ&
public class CountCache { N `F~n%N
public static LinkedList list=new LinkedList(); Jd^,]
/** Creates a new instance of CountCache */ 'o>B'$
public CountCache() {} `W/>XZl+t
public static void add(CountBean cb){ I->Ss},U
if(cb!=null){ x-.?HS[
list.add(cb); <.izVD4/Gg
} (7=!+'T"
} !6>~?gNd
} {w^+\]tC
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CountControl.java /F'sb[
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/* H{?vbqQ
* CountThread.java Jk=I^%~
* KRMQtgahc
* Created on 2007年1月1日, 下午4:57 =\wxsL
* fbKkq.w
* To change this template, choose Tools | Options and locate the template under S<@7_I
* the Source Creation and Management node. Right-click the template and choose J!pygn O
* Open. You can then make changes to the template in the Source Editor. jeH~<t{
*/ e:n<EnT
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package com.tot.count; Jx7C'~,J
import tot.db.DBUtils; 6'G6<8>-
import java.sql.*; 5T2CISmu
/** G5aieD.#
* 8hJ%JEzga
* @author PV\+P6aIb
*/ 4V i`* !
public class CountControl{ ,*hLFaR-
private static long lastExecuteTime=0;//上次更新时间 bITPQ7+
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 BB*f4z$Y%
/** Creates a new instance of CountThread */ ;=;
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public CountControl() {} vyX\'r.~7
public synchronized void executeUpdate(){ SVs_dG$
Connection conn=null; 7k9G(i[-+
PreparedStatement ps=null; vMt/u?oB
try{ F9E<K]7K
conn = DBUtils.getConnection(); 6qoyiT%P&
conn.setAutoCommit(false); -$jEfi4I
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %GA"GYL9'
for(int i=0;i<CountCache.list.size();i++){ 33ef/MElD$
CountBean cb=(CountBean)CountCache.list.getFirst(); S^>,~R.TX
CountCache.list.removeFirst(); >
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ps.setInt(1, cb.getCountId()); ()Y4v
ps.executeUpdate();⑴ ,p2s:&"
//ps.addBatch();⑵ 7-
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} NS%xTLow-
//int [] counts = ps.executeBatch();⑶ f'-i o<.
conn.commit(); SmdjyK1~8
}catch(Exception e){ B~JwHwIhA
e.printStackTrace(); &U
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} finally{ %g$V\zmU
try{ hp*/#D
if(ps!=null) { (-xS?8x$
ps.clearParameters(); |_*O '#jx
ps.close(); x:>wUhzZ
ps=null; y8L D7<1u
} eg?<mKrZ
}catch(SQLException e){} WDc+6/<
DBUtils.closeConnection(conn); wNtx]t_M
} pP?MWe
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} qY<'<T4\
public long getLast(){ [t7]{d*
return lastExecuteTime; ^ZhG>L*
} wEE\+3b)
public void run(){ 2FF4W54I
long now = System.currentTimeMillis(); 0]=i}wL 8
if ((now - lastExecuteTime) > executeSep) { N#7QzB9]
//System.out.print("lastExecuteTime:"+lastExecuteTime); %Nhx;{
//System.out.print(" now:"+now+"\n"); ng:9 l3x
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); :x{NBvUIc
lastExecuteTime=now; Q`D~5ci
executeUpdate(); OCJnjlV%
} `m?c;,\
else{ `'c_=<&n
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); e~@[18
} =fve/_Q~
} !z<%GQ CT
} C] 9p5Hs
//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 tqeZ#w7
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类写好了,下面是在JSP中如下调用。 ryCI>vJz
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<% ;3: q?&
CountBean cb=new CountBean(); 1_
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); M57T2]8,
CountCache.add(cb); (+u39NQV
out.print(CountCache.list.size()+"<br>"); g'=B%eO$j:
CountControl c=new CountControl(); $dzy%lle
c.run(); dd%h67J2<
out.print(CountCache.list.size()+"<br>"); )\be2^p
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