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: XcQ'(
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CountBean.java +luW=j0V
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/* h2edA#bub
* CountData.java o8S)8_3
* UjQi9ELoJ
* Created on 2007年1月1日, 下午4:44 oNBYJ]t
* g/m%A2M&aH
* To change this template, choose Tools | Options and locate the template under ,h$j%->U
* the Source Creation and Management node. Right-click the template and choose 3mM.#2=@>
* Open. You can then make changes to the template in the Source Editor. atWAhN
*/ XWFuAE
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package com.tot.count; (#k2S-5
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/** B\Y!5$
* gw9:1S
* @author a0x/ ?)DO
*/ )haHI)xR
public class CountBean { *G0r4Ui$
private String countType; -* ;`~5
int countId; #$9rH
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/** Creates a new instance of CountData */ o*WI*Fb'
public CountBean() {} a"0'cgB}
public void setCountType(String countTypes){ z"lRfOWI
this.countType=countTypes; jP|(y]!
} \muC_9ke
public void setCountId(int countIds){ )|@UY(VZ^
this.countId=countIds; nxh9'"th
} ~WG#Zci-
public String getCountType(){ p![CH
return countType; Y+I`XeY
} e#$ZOK)`
public int getCountId(){ L1E\^)
return countId; s"\o6r
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} S}cm.,/w
} o\YF_235
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CountCache.java gRdg3qvU
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/* #0j,1NpL
* CountCache.java xN#. Pm~
* B]YY[i
* Created on 2007年1月1日, 下午5:01 $?u ^hMU=
* i
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* To change this template, choose Tools | Options and locate the template under Ka\%kB>*`
* the Source Creation and Management node. Right-click the template and choose SggS8$a`
* Open. You can then make changes to the template in the Source Editor. fX2PteA0qX
*/ `&yUU2W
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package com.tot.count; pJE317 p'
import java.util.*; U ]6Hml;l
/** yegTKoY
* B[0XzV]Z
* @author %%w]-`^h,
*/ 3q.O^`y FU
public class CountCache { hOSkxdi*^
public static LinkedList list=new LinkedList(); (9J,Qs[;
/** Creates a new instance of CountCache */ cEd!t6Z
public CountCache() {} ]='E&=nc
public static void add(CountBean cb){ {<- BU[H
if(cb!=null){ O5Xu(q5+
list.add(cb); {^#62Y
} x1kb]0s<-
} DN@T4!
} $Y4;Xe=
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CountControl.java mSzBNvci
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/* @M-+-6+
* CountThread.java 2|)3Ly9
* ~a5p_x P
* Created on 2007年1月1日, 下午4:57 [EJ[Gg0m
* :,=no>mMx
* To change this template, choose Tools | Options and locate the template under v&B*InR?+
* the Source Creation and Management node. Right-click the template and choose /0mbG!Ac
* Open. You can then make changes to the template in the Source Editor. +BRmqJ3
*/ HX{O@
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package com.tot.count; yjVPaEu]aU
import tot.db.DBUtils; <"@~
import java.sql.*; Nd~?kZZu
/** %Y` @>P'
* )-2o}KU]>
* @author E
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*/ j#b?P=|l
public class CountControl{ :hG?} [-2
private static long lastExecuteTime=0;//上次更新时间 $3sS&i<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !0~$u3[b
/** Creates a new instance of CountThread */ Fr)G
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public CountControl() {} +QIM~tt)
public synchronized void executeUpdate(){ por[p\ M.
Connection conn=null; V>j6Juh
PreparedStatement ps=null; lV-7bZ
try{ )dJaF#6j
conn = DBUtils.getConnection(); RvYH(!pQ
conn.setAutoCommit(false); # a
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); m[C-/f^u|
for(int i=0;i<CountCache.list.size();i++){ */n)_
CountBean cb=(CountBean)CountCache.list.getFirst(); +!V*{<K
CountCache.list.removeFirst(); /)xG%J7H
ps.setInt(1, cb.getCountId()); u|7d_3 ::
ps.executeUpdate();⑴ i=-zaboo
//ps.addBatch();⑵ 4XDR?KUM
} k|,pj^
//int [] counts = ps.executeBatch();⑶ 2@o_7w98
conn.commit(); FG-w7a2mn
}catch(Exception e){ Nf>1`eP
e.printStackTrace(); 02} &h
} finally{ A}sb2P
try{ $L.0$-je4
if(ps!=null) { m El*{]
ps.clearParameters(); IEdC
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ps.close(); |*7uF<ink6
ps=null; a8-2:8Su
} ky#d`
}catch(SQLException e){} d^IOB|6Q
DBUtils.closeConnection(conn); :Q sGwhB
} gO?+:}!
} /b20!3
public long getLast(){ glh2CRUj
return lastExecuteTime; "';'*x
} z_eP
public void run(){ 5,'?NEyw
long now = System.currentTimeMillis(); [SgP1>M
if ((now - lastExecuteTime) > executeSep) { r:y*l4
//System.out.print("lastExecuteTime:"+lastExecuteTime); h%(dT/jPL)
//System.out.print(" now:"+now+"\n"); {>G\3|^D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s@f4f__(]
lastExecuteTime=now; 0yXUVKq3
executeUpdate(); Zbxd,|<|
} 7Rj!vj/
else{ ,*r"cmz
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); tq?lF$mM:
} BSG_),AH
} L*9^-,
} n6[bF"v
//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 r^&{0c&o
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类写好了,下面是在JSP中如下调用。 tn;e
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<% $GUSTV
CountBean cb=new CountBean(); XZA3TZ
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); fSl+;|Kn
CountCache.add(cb); >\8Bu#&s4
out.print(CountCache.list.size()+"<br>"); tuK"}HepB
CountControl c=new CountControl(); b/ 'fC%o,
c.run(); t/_w}
out.print(CountCache.list.size()+"<br>"); -c%GlpZw
%>