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: 1u_< 1X3
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CountBean.java Uc]sWcR
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/* Y;>D"C..
* CountData.java j55OG~)
* 5_Oxl6#
* Created on 2007年1月1日, 下午4:44 *|3G"B{w6
* w(!COu
* To change this template, choose Tools | Options and locate the template under *o#P)H
* the Source Creation and Management node. Right-click the template and choose Xm~N Bt
* Open. You can then make changes to the template in the Source Editor. |OO2>(Fj
*/ -AM(-
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package com.tot.count; Y
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/** b|u0a6
* q,.@<s W
* @author ::p(ViYG
*/ k6^!G "
public class CountBean { crr#tad.
private String countType; 80Z'1'u0
int countId; hta y-
/** Creates a new instance of CountData */ Bx ru7E"
public CountBean() {} xC -&<s
public void setCountType(String countTypes){ Qjd<%!]+\
this.countType=countTypes; nb #)$l
} W=!di3IA
public void setCountId(int countIds){ qnTW?c9Z5
this.countId=countIds; L(_bf/@3
} ,];QzENw
public String getCountType(){ t}f,j^`e
return countType; +YCKd3/
} LAU\.d
public int getCountId(){ 'qiDh[ATa
return countId; 1'BC
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} uN9J?j*ir
} gEkH5|*Y
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CountCache.java R}HNi(%"
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/* m"RSDM!
* CountCache.java h0;R*c
* }MW+K&sIh
* Created on 2007年1月1日, 下午5:01 b!c2j
* \??20iz
* To change this template, choose Tools | Options and locate the template under &v g[k#5
* the Source Creation and Management node. Right-click the template and choose 3&KRG}5
* Open. You can then make changes to the template in the Source Editor. 4s7&*dJ
*/ }^zsN`
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package com.tot.count; I7Xm~w!{qk
import java.util.*; (KnU-E]L
/** ytyB:# J
* Y [%<s/
* @author "-:-!1;Ji
*/ U~q2j#pJ
public class CountCache { 87yZd8+)
public static LinkedList list=new LinkedList(); 9oTtH7%
/** Creates a new instance of CountCache */ W*^_Ul|
public CountCache() {} f yhBfA:u
public static void add(CountBean cb){ _Z_R\
if(cb!=null){ Df.eb|[{
list.add(cb); >Q[3t79^
} fRomP-S
} X|dlVNL8p
} }}u16x}*n
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CountControl.java }0AoV&75
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/* H_FT%`iM
* CountThread.java PpezWo)9
* !Wz4BBU8o
* Created on 2007年1月1日, 下午4:57 `CY c>n"
* WYd9p; k
* To change this template, choose Tools | Options and locate the template under r2T$
;m.
* the Source Creation and Management node. Right-click the template and choose vq:?a
* Open. You can then make changes to the template in the Source Editor. 0^K2"De
*/ a[@Y>
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package com.tot.count; 7\[)5j
import tot.db.DBUtils; u{LtyDnik
import java.sql.*; iaHL&)[YK
/** ] ]XXcQ,A
* W:JR\KKU
* @author TW-^C;
*/ N^4CA@'{
public class CountControl{ xiOAj"}~
private static long lastExecuteTime=0;//上次更新时间 c'SjH".[
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ;$'D13
/** Creates a new instance of CountThread */ aY0{v X
public CountControl() {} 6o&ZS @
public synchronized void executeUpdate(){ `APeS=<
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Connection conn=null; G.]'pn
PreparedStatement ps=null; !3`X Gg
try{ jx14/E+^
conn = DBUtils.getConnection(); qi$nG_<<Z
conn.setAutoCommit(false); %>Mcme>(W
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >f70-D28
for(int i=0;i<CountCache.list.size();i++){ 5O[\gd-
CountBean cb=(CountBean)CountCache.list.getFirst(); #@L5yy2
CountCache.list.removeFirst(); 1|:'jK#gE
ps.setInt(1, cb.getCountId()); /<1zzeHRSD
ps.executeUpdate();⑴ +h@ZnFp3
//ps.addBatch();⑵ oc;4;A-;`c
} DO6
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//int [] counts = ps.executeBatch();⑶ 17#t 7Yk
conn.commit(); VI]~uTV
}catch(Exception e){ QXEz[R
e.printStackTrace(); Y 2[ik<
} finally{ c!N#nt_<
try{ 7n]ukqZ
if(ps!=null) { lofP$
ps.clearParameters(); S/dj])g
ps.close(); GD%qrK?
ps=null; Q7-'5s
} OmlM9cXm^4
}catch(SQLException e){} BvP++,a&Sa
DBUtils.closeConnection(conn); -?w3j9kk>
} |f1RhB
} i?861Hu
public long getLast(){ Ffig0K+`
return lastExecuteTime; 8ib e#jlg
} gts09{"}Y
public void run(){ b9VI(s>
long now = System.currentTimeMillis(); N
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if ((now - lastExecuteTime) > executeSep) { /9o6R:B
//System.out.print("lastExecuteTime:"+lastExecuteTime); V/tl-;W
//System.out.print(" now:"+now+"\n"); iUq_vQ@}}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); q);oO\<
lastExecuteTime=now; 6Ev+!!znu
executeUpdate(); mbHMy[R
} ']N\y6=fn9
else{ KQ ^E\,@o
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); q8MyEoc:n
} <?%49
} r`i.h ^2De
} MzF,is
//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 pm2]
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类写好了,下面是在JSP中如下调用。 n[\L6}
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<% / 2MhP=,
CountBean cb=new CountBean(); E8 5TCS1
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t ?05
CountCache.add(cb); &yI>A1
out.print(CountCache.list.size()+"<br>"); Oj8D+sC{
CountControl c=new CountControl(); $`P]%I}
c.run(); :lu "14
out.print(CountCache.list.size()+"<br>"); bI8')a
%>