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: .gkPG'm[
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CountBean.java _Il9s#NA%
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/* a4CNPf<$
* CountData.java v7OV;ea$
* [oN> :
* Created on 2007年1月1日, 下午4:44 dVGUhXN6
* JO^
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* To change this template, choose Tools | Options and locate the template under ^Er`{|o6u
* the Source Creation and Management node. Right-click the template and choose oY6|h3T=Q$
* Open. You can then make changes to the template in the Source Editor. NUnc"@
*/ @)'@LF1Z
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package com.tot.count;
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/** bq&S?! =s
* N[bf.5T
* @author ?*mbce[
*/ +G[HZ,FL
public class CountBean { |mE+f]7$
private String countType; H|:)K^o
int countId; )?IA`7X
/** Creates a new instance of CountData */ )~mc1U`b
public CountBean() {} [
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public void setCountType(String countTypes){ H!>oLui
this.countType=countTypes; .&} 4
} 95 .'t}
public void setCountId(int countIds){ 3XlnI:w=
this.countId=countIds; MMr7,?,$
} hYv 6-5_
public String getCountType(){ <J}9.k
return countType; |QTqa~~B
} 8EEQV} 4
public int getCountId(){ IS4K$Ac.
return countId; W#\};P
} "XsY~
} 2CgIY89O
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CountCache.java rJQ|Oi&1i
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/* NE%yv,B
* CountCache.java I_I;.Ik
* lnSE+YJ>
* Created on 2007年1月1日, 下午5:01 g+r{>x
* `&[:!U2]F
* To change this template, choose Tools | Options and locate the template under 8Y~T$Yj^
* the Source Creation and Management node. Right-click the template and choose 78J.~v/
* Open. You can then make changes to the template in the Source Editor.
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*/ DSZhl-uGM
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package com.tot.count; 4x?u5L
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import java.util.*; 9.#R?YP$
/** >8;%F<o2
* d4h(F,K7V
* @author )[X!/KR90
*/ &Wz:-G7<n
public class CountCache { bK;aV&
public static LinkedList list=new LinkedList(); IeI%X\G
/** Creates a new instance of CountCache */ NWwtq&pz2
public CountCache() {} UMW^0>Z!v
public static void add(CountBean cb){ $hp?5KM
if(cb!=null){ (IHBib "
list.add(cb); il%tu<E#J~
} !;C(pnE
} R{A/+7!
} H08YMP>dc
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CountControl.java f>[;|r@K
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/* X&oy.Roo
* CountThread.java -vfu0XI~
* f_2^PF>?
* Created on 2007年1月1日, 下午4:57 5nqdY*
* PlRs-% d
* To change this template, choose Tools | Options and locate the template under Sz@?%PnU|
* the Source Creation and Management node. Right-click the template and choose 2#M:JgWV
* Open. You can then make changes to the template in the Source Editor. }gRLW2&mR>
*/ f8jz49C
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package com.tot.count; 3v+}YT{>b
import tot.db.DBUtils; Mf13@XEo
import java.sql.*; K2`WcEe
/** PH!B /D5G
* G/44gKl
* @author *t9qH
*/ vm}.gQ
public class CountControl{ 1V$B^/ _
private static long lastExecuteTime=0;//上次更新时间 -"9)c^KVx
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ']e4!
/** Creates a new instance of CountThread */ Xtnmh)'K~#
public CountControl() {} 'z!#E!i
public synchronized void executeUpdate(){ f|1FqL+T]
Connection conn=null; <f{`}drp/
PreparedStatement ps=null; Cy'W!qH
try{ <%uZwk>#
conn = DBUtils.getConnection(); rWKLxK4oU
conn.setAutoCommit(false); \1D,Kx;Cb
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); S%#Mu|
for(int i=0;i<CountCache.list.size();i++){ h,?Yw+#o"
CountBean cb=(CountBean)CountCache.list.getFirst(); ;QD;5
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CountCache.list.removeFirst(); }U1shG[
ps.setInt(1, cb.getCountId()); Dq4}VkY
ps.executeUpdate();⑴ >8t[EsW/
//ps.addBatch();⑵ &`2*6
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} [;8fL
//int [] counts = ps.executeBatch();⑶
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conn.commit(); [N+ruc?)
}catch(Exception e){ *
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e.printStackTrace(); 2;r^~:
} finally{ urjp&L&
try{ &Sp:?I-
if(ps!=null) { RW8u0 ?b
ps.clearParameters(); oioN0EuDk
ps.close(); Ps4A
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ps=null; ` &7?+s
} *X5LyO3-gP
}catch(SQLException e){} |q)Q<%VS'
DBUtils.closeConnection(conn); A~SSu.L@
} Nx
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} O4mWsr
public long getLast(){ S^=/}PT'
return lastExecuteTime; 30`H
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} n :kxG
public void run(){ ~36XJ
long now = System.currentTimeMillis(); uoc-qmm
if ((now - lastExecuteTime) > executeSep) { e}w!]
//System.out.print("lastExecuteTime:"+lastExecuteTime); Kx!|4ya,
//System.out.print(" now:"+now+"\n"); scwlW
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// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); s_kd@?=`x
lastExecuteTime=now; !gQ(1u|r
executeUpdate(); hmk5
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} :Xr3 3
else{ ~,1X>N"
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <rxem(PPu
} 1H@F>}DP
} $R36`wk
} `o'sp9_3
//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 nwH|Hs riU
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类写好了,下面是在JSP中如下调用。 sM[c\Z]
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<% J3^Ir [
CountBean cb=new CountBean(); ]2
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); u:?RdB}B_@
CountCache.add(cb); v>l?d27R
out.print(CountCache.list.size()+"<br>"); [C\?}.+v
CountControl c=new CountControl(); mt7:`-
c.run(); :7*\|2zA
out.print(CountCache.list.size()+"<br>"); wO
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