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: fv 1!^CDia
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CountBean.java vSHIl"h
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/* ?#{2?%_
* CountData.java T\$^>@
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* Created on 2007年1月1日, 下午4:44 N6m*xxI{
* (
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* the Source Creation and Management node. Right-click the template and choose %q\P 'cK
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package com.tot.count; `sp'Cl!
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/** rc{[\1 -N
* l4B O@
* @author %imBGh
*/ S|5lx7
public class CountBean { HDae_.
private String countType; 7<C~D,x6
int countId; W U4vb
/** Creates a new instance of CountData */ kl{OO%jZ
public CountBean() {} odT7Gq
public void setCountType(String countTypes){ />j+7ts
this.countType=countTypes; BNKo6:wy
} fKK-c9F
public void setCountId(int countIds){ B,na
this.countId=countIds; x2IU PM
} G<WDyoN=O
public String getCountType(){ @W5hrei
return countType; a^)4q\E
} r
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public int getCountId(){ @xM!:
return countId; d}B_ll#j-
} \5pAG
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} iJj?~\zp
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CountCache.java ;g)Fhdy!
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/* =K<I)2
* CountCache.java W/F4wEODY
* c+K=pp@
* Created on 2007年1月1日, 下午5:01 uJ5%JB("E
* UFY~D"%/
* To change this template, choose Tools | Options and locate the template under ZK_@.O+ ]
* the Source Creation and Management node. Right-click the template and choose ~esEql=Q3'
* Open. You can then make changes to the template in the Source Editor. +AC-f2
*/ v]Q_
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package com.tot.count; r D!.N
import java.util.*; |>fS"u
/** 1?#p !;&
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* @author )/i|"`)>_
*/ 1^"aR#
public class CountCache { WuQ<AS=
public static LinkedList list=new LinkedList(); #1hz=~YO
/** Creates a new instance of CountCache */ .AI'L|FQ%c
public CountCache() {} v+_Y72h*a
public static void add(CountBean cb){ )B5gs%u]
if(cb!=null){ <XcMc<h~
list.add(cb); U:p"IY#%
} F0^~YYRJV
} W%Nu]9T
} lNeF>zz
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CountControl.java 7a_n\]t465
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/* +6Fdi*:
* CountThread.java 'oeg[
* {gHscj;SM
* Created on 2007年1月1日, 下午4:57 z ex.0OT;
* SIVLYi
* To change this template, choose Tools | Options and locate the template under X^ ]$/rI)
* the Source Creation and Management node. Right-click the template and choose yl+)I
* Open. You can then make changes to the template in the Source Editor. K[yJu 4
*/ _eeX]xSSl
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package com.tot.count; csA.3|rv
import tot.db.DBUtils; tnbs]6
import java.sql.*; w^6N
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/** 3EX&.OL!
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* @author P\0%nyOG(%
*/ *H<g9<Dn
public class CountControl{ QgM_SY|Rj
private static long lastExecuteTime=0;//上次更新时间 &>B>+}'
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 )$N{(Cke2T
/** Creates a new instance of CountThread */ =WRU<`\
public CountControl() {} R6o<p<fTh
public synchronized void executeUpdate(){ { RX|
Connection conn=null; jY6=+9Jz5
PreparedStatement ps=null; rd~W.b_b
try{ 8VGXw;(Y,d
conn = DBUtils.getConnection(); (mr`?LI}
conn.setAutoCommit(false); &Zy=vk*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ;4#8#;
for(int i=0;i<CountCache.list.size();i++){ k3h53QTmC
CountBean cb=(CountBean)CountCache.list.getFirst(); s-S"\zX\D
CountCache.list.removeFirst(); M\4;d #
ps.setInt(1, cb.getCountId()); BQ)43Rr>
ps.executeUpdate();⑴ YHtI%
//ps.addBatch();⑵ aq| [g
} Jm,X~Si
//int [] counts = ps.executeBatch();⑶ w[[@&T\`
conn.commit(); fx"+ZR
}catch(Exception e){ #IA(*oM
e.printStackTrace(); qinQ5 t
} finally{ r>@/XYK&\
try{ b<cM[GaV~
if(ps!=null) { n.>'&<H>9
ps.clearParameters(); \-id[zKb
ps.close(); z`7C)p:
ps=null; ?
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} fT~<C
{
}catch(SQLException e){} R@aT=\u+
DBUtils.closeConnection(conn); 9+|,aG s
} Io X9yGq
} -T6%3>h
public long getLast(){ >{=RQgGy
return lastExecuteTime; =W^L8!BE'
} Z6ex<[`I
public void run(){ ?kefRev<#h
long now = System.currentTimeMillis(); R6.#gb8^oS
if ((now - lastExecuteTime) > executeSep) { Q'M Ez
//System.out.print("lastExecuteTime:"+lastExecuteTime); 3!UP>,!
//System.out.print(" now:"+now+"\n"); 3`q`W9
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); _j
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lastExecuteTime=now; aJ@qB9(ZBe
executeUpdate(); ]}c=U@D,9
} $X]v;B)J|
else{ z:7F5!Z
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ?bA]U:
} 9}_f\Bs
} DYl{{L8@
} )q-!5^ak
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 jd'R2e
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类写好了,下面是在JSP中如下调用。 Y)RikF >
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<% .H.v c_/
CountBean cb=new CountBean(); ^:j:;\;
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <p
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CountCache.add(cb); q0<`XDD`
out.print(CountCache.list.size()+"<br>"); )ISTb
CountControl c=new CountControl(); 9?6$ 2I
c.run(); . r"?w
out.print(CountCache.list.size()+"<br>"); 4 l(o{{
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