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: f^e6<5gdf
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CountBean.java +&KQ28r
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/* weMww,: ^[
* CountData.java HEqWoV]{d
* K7I&sS^x
* Created on 2007年1月1日, 下午4:44 04!(okubyp
* 7:=5"ScV
* To change this template, choose Tools | Options and locate the template under 0e["]Tlnm
* the Source Creation and Management node. Right-click the template and choose l6[lJ0Y
* Open. You can then make changes to the template in the Source Editor. \F, DA"K_
*/ !~<siy
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package com.tot.count; ,(G%e
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/** NkxCs
* 2}}?'PwwT
* @author Ja]oGT=e
*/ &Y@#g9G
public class CountBean { 3HyhEVR-#~
private String countType; M4Z@O3OIE
int countId; !}3,B28
/** Creates a new instance of CountData */ P,gdnV
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public CountBean() {} 151tXSzLT
public void setCountType(String countTypes){ "fQRk
this.countType=countTypes; C-P06Q]
} c.H?4j7ga
public void setCountId(int countIds){ PBks`
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this.countId=countIds; e`{0d{Nd
} |P6EO22p
public String getCountType(){ I.}1JJF*
return countType; ;)DzCc/
} z}}]jR\y?
public int getCountId(){ V9x8R
return countId; e1
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} zvv:dC/p<
} )He#K+[}^4
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CountCache.java %R0v5=2'
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/* xFp<7p
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* CountCache.java +-068k(
* ;~HNpu$
* Created on 2007年1月1日, 下午5:01
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* 'Tb0-1S?
* To change this template, choose Tools | Options and locate the template under ?SY<~i<K-
* the Source Creation and Management node. Right-click the template and choose 71B3a
* Open. You can then make changes to the template in the Source Editor. YTY%#"
*/ 4YbC(f
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package com.tot.count; U2*6}c<
import java.util.*; ^o<:;{
/** SA6hbcYk
* ^[h2% c$
* @author & %}/AoU
*/ TW`mxj_J2
public class CountCache { g jG2
public static LinkedList list=new LinkedList(); mp`PE=
/** Creates a new instance of CountCache */ x;$|#]+
public CountCache() {} m^!Sv?hV
public static void add(CountBean cb){ 1JTbCS
if(cb!=null){ .PVLWW
list.add(cb); eVnbRT2y&
} ?)A2Kw>2
} `]2@_wa
} d5xxb _oE
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CountControl.java ui.'^F<
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/* 7#4%\f+'t
* CountThread.java &>}.RX]t
* ;cSGlE |
* Created on 2007年1月1日, 下午4:57 :B#EqeI
* y~#\#w{
* To change this template, choose Tools | Options and locate the template under zi!#\s^
* the Source Creation and Management node. Right-click the template and choose t/:w1rw
* Open. You can then make changes to the template in the Source Editor. O4+F^+qN
*/ <GW R7rUH
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package com.tot.count; N2~$rpU3
import tot.db.DBUtils; cIw
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import java.sql.*; :zL 393(
/** < tQc_
* l=Wd,$\
* @author 7u%a/ <
*/ QJ<[Zx
public class CountControl{ n! .2aq
private static long lastExecuteTime=0;//上次更新时间 H/i<_L P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <Ry$7t,
/** Creates a new instance of CountThread */ ko[TDh$T5
public CountControl() {} Vq}r_#!Q
public synchronized void executeUpdate(){ QaMDGD
Connection conn=null; eOrYa3hQ
PreparedStatement ps=null; CM 9P"-
try{ J~J@ ]5/
conn = DBUtils.getConnection(); 7Jx%JgF
conn.setAutoCommit(false); GJak.,0t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); .)ST[G]WK
for(int i=0;i<CountCache.list.size();i++){ 1)U}i ^
CountBean cb=(CountBean)CountCache.list.getFirst(); SMq9j,k
CountCache.list.removeFirst(); qc0 B<,x7
ps.setInt(1, cb.getCountId()); Zd<[=%d
ps.executeUpdate();⑴ R#0{Wg0O)
//ps.addBatch();⑵ W(k:Pl#
} UD*+"~
//int [] counts = ps.executeBatch();⑶ ]V<"(?,K
conn.commit(); x YT}>#[
}catch(Exception e){ EhXiv#CZ
e.printStackTrace(); e{t=>vry
} finally{ nYov>x]
try{ _W9&J&l0so
if(ps!=null) { rbh[j@s@
ps.clearParameters(); 94z8B;+H]
ps.close(); ^gm>!-Gx
ps=null; A7'b Nd6f9
} 5^F]tRz-
}catch(SQLException e){} uu3M{*}
DBUtils.closeConnection(conn); _<u;4RO(s
} [2H[5<tH
} ,Oi^ySn
public long getLast(){ .YiaXP
return lastExecuteTime; =jUnM>23
} 56ZrCr
public void run(){ 0ny{)Sd6um
long now = System.currentTimeMillis(); R92R}=G!
if ((now - lastExecuteTime) > executeSep) { K`gc 4:A
//System.out.print("lastExecuteTime:"+lastExecuteTime); J9a $AU*
//System.out.print(" now:"+now+"\n"); {5 Kz' FT
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); e`ex]py<C
lastExecuteTime=now; !w=,p.?V=
executeUpdate(); .Cfp'u%\;
} hZ o5p&b
else{ \1{_lynD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); I7b i@t
} v$JLDt_
} @Z=wE3T@
} /hfUPO5
//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 wiBuEaUkW
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类写好了,下面是在JSP中如下调用。 \>;%Ji
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<% D2?S,9+E_
CountBean cb=new CountBean(); iPkT*Cl8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); qzlER
CountCache.add(cb); t[j9R#02?
out.print(CountCache.list.size()+"<br>"); 2$DSBQEx
CountControl c=new CountControl(); 5*XH6g F
c.run(); _Ff".t<"
out.print(CountCache.list.size()+"<br>"); 7?"9J`*
%>