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: Z/-%Eb]L1
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CountBean.java Bl`e+&b
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/* Kyl(
* CountData.java dje3&a
* ) 0}o bPp
* Created on 2007年1月1日, 下午4:44 LiV]!*9$KG
* >^InNJd
* To change this template, choose Tools | Options and locate the template under u]dpA
* the Source Creation and Management node. Right-click the template and choose Z,iklB-
* Open. You can then make changes to the template in the Source Editor. yAi4v[
*/ T}!7LNE
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package com.tot.count; ,+'f unH
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/** ae!_u
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* }f-rWe{gs>
* @author IL%&*B
*/ W2^eE9
public class CountBean { aO<d`DTyJ
private String countType; nAts.pVy"
int countId; V|a59[y?
/** Creates a new instance of CountData */ 9h0|^ttF
public CountBean() {} > %Y#(_~a
public void setCountType(String countTypes){ T3?kabbF
this.countType=countTypes; ;F0A\5I
} T@vVff
public void setCountId(int countIds){ 1}ToR=
this.countId=countIds; [e^i".
} ;N1FP*
public String getCountType(){ k2+Z7#2n
return countType; y4?>5{`W
} R,^FJ
public int getCountId(){ ,*lK4?v
return countId; %xk]y&jv
} M]_vb,=1
} \Fj4Gy?MW
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CountCache.java Bf*
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/* pEaH^(I*
* CountCache.java 0>?mF]M
* ~~fL`"
* Created on 2007年1月1日, 下午5:01 WYzY#-j
* e4`KnHsL
* To change this template, choose Tools | Options and locate the template under QB@*/Le
* the Source Creation and Management node. Right-click the template and choose ome>Jbdhe
* Open. You can then make changes to the template in the Source Editor. jS- QTG!=
*/ eBN>|mE4N
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package com.tot.count; ]D]K_`!K
import java.util.*; eb8_guZ
/** Q@j:b]Y9
* q{5Vq_s\
* @author OB^
*/ {U<htl4
public class CountCache { 4Sl^cKb$7
public static LinkedList list=new LinkedList(); eo,]b1C2n
/** Creates a new instance of CountCache */ .LS.Z
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public CountCache() {} D0]9
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public static void add(CountBean cb){ EnUo B<
if(cb!=null){ 4C[gW
list.add(cb); d)AkA\neWo
} a*D|$<V
} \C6m.%%={R
} (J;?eeP
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CountControl.java ujSzm=_P
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/* [&4y@
* CountThread.java He@= bLLa
* ZEMo`O
* Created on 2007年1月1日, 下午4:57 ?@,:\ ,G
* z&:[.B
* To change this template, choose Tools | Options and locate the template under u,]yd*
* the Source Creation and Management node. Right-click the template and choose df)1}/*L
* Open. You can then make changes to the template in the Source Editor. gbh:Y}_FU
*/ $R5-JvJJH
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package com.tot.count; axl?t|~I
import tot.db.DBUtils; +Q9HsfX/
import java.sql.*; ?=G H{
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/** [/kO>
* 3_>1j
* @author 7/yd@#$X
*/ lu}[XN
public class CountControl{ #}Cwn$
private static long lastExecuteTime=0;//上次更新时间 0t&H1xsxX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 sg y
/** Creates a new instance of CountThread */ kO#`m]
public CountControl() {} )}aF=%
public synchronized void executeUpdate(){ 4~/6d9f
Connection conn=null; tv{.iM|V c
PreparedStatement ps=null;
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try{ ][mc^eI0s|
conn = DBUtils.getConnection(); lyPXlt
conn.setAutoCommit(false); W7
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); z~_\onC
for(int i=0;i<CountCache.list.size();i++){ -jy"?]ve.
CountBean cb=(CountBean)CountCache.list.getFirst(); Rju8%FRO
CountCache.list.removeFirst(); &Y>u2OZ
ps.setInt(1, cb.getCountId()); -$q/7,os
ps.executeUpdate();⑴ |{nI.>
//ps.addBatch();⑵ LKZI@i)
} }X?*o`sW
//int [] counts = ps.executeBatch();⑶ WWLVy(
conn.commit(); _7<U[63
}catch(Exception e){ d7P @_jO6
e.printStackTrace(); ba ?k:b
} finally{ vB{b/xmah
try{ ?uN(" I
if(ps!=null) { )-{~7@yqZ
ps.clearParameters(); a8 1%M
ps.close(); @rMW_7[y
ps=null; 9|`@czw
} <j#EyGAV
}catch(SQLException e){} -T8
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DBUtils.closeConnection(conn); !O-+h0Z
} |gz,Ip{
} SDwSlwf
public long getLast(){ bij?q\
return lastExecuteTime; C] w< &o
} 6~S0t1/t?
public void run(){ U!5*V9T~J
long now = System.currentTimeMillis(); (n/1:'
if ((now - lastExecuteTime) > executeSep) { )8SP$
//System.out.print("lastExecuteTime:"+lastExecuteTime); <&2,G5XA
//System.out.print(" now:"+now+"\n"); =1VH5pVr}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); m { fQL
lastExecuteTime=now; lo: ~~l
executeUpdate(); c5R{Sl
} yh:,[<q
else{ VZoOdR:d
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); }v,THj
} bEKLameKv
} DO1{r/Ib.{
} Oy&'zigJ
//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 q#`^EqtUF
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类写好了,下面是在JSP中如下调用。
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<% Z L</
CountBean cb=new CountBean(); ([*t.
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); DcA'{21
CountCache.add(cb); ~S6 {VK.
out.print(CountCache.list.size()+"<br>"); njMy&$6a##
CountControl c=new CountControl(); ~P_kr'o
c.run(); P{eRDQ=
out.print(CountCache.list.size()+"<br>"); #pSOZX
%>