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: juHL$SGC
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CountBean.java ?6:qAFw
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/* kOQ)QX
* CountData.java I0}.!
* ztO)~uL
* Created on 2007年1月1日, 下午4:44 U<j5s\Y,
* lCU clD
* To change this template, choose Tools | Options and locate the template under & &}_[{fc
* the Source Creation and Management node. Right-click the template and choose 6(8F4[D
* Open. You can then make changes to the template in the Source Editor. SxRJ{m~
*/ j[r}!;O
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package com.tot.count; ZsP ^<
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/** HgQjw!
* !eyLh&]5
* @author ;73S;IPR
*/ 2)=whnFS
public class CountBean { W> pe-
private String countType; JqzoF}WH
int countId; rRe5Q
/** Creates a new instance of CountData */ f-F=!^.
public CountBean() {} +VUkV-kP
public void setCountType(String countTypes){ {lds?AuK
this.countType=countTypes; 2w.FC
} ,XT,t[w
public void setCountId(int countIds){ ,%9XG077
this.countId=countIds; Vh\_Ko\V5
} }QI \K
public String getCountType(){ e/D{^*~S
return countType; <,~OcJG(
} x/s:/YN'
public int getCountId(){ |
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return countId; #*.!J zOg
} ^OY$
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} }WsPu o
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CountCache.java iE'_x$i
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/* 2y!n c%
* CountCache.java m^ xTV-#l@
* e)e(f"t6Q
* Created on 2007年1月1日, 下午5:01 qR@ESJ_
* Lvf<g}?4
* To change this template, choose Tools | Options and locate the template under Z[@ i/. I
* the Source Creation and Management node. Right-click the template and choose t utk*|S
* Open. You can then make changes to the template in the Source Editor. e1Db
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*/ e4YfJd
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package com.tot.count; j
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import java.util.*; pf8'xdExH)
/** [E9iuym
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* @author \n_7+[=E
*/ ='"Yj
public class CountCache { q2%cLbI
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public static LinkedList list=new LinkedList(); {-5)nS^_
/** Creates a new instance of CountCache */ $1 ])>m_ct
public CountCache() {} ,buX|
public static void add(CountBean cb){ IUOf/mM5
if(cb!=null){ ;u2[Ww~k
list.add(cb); Mq91HmC(@
} &E`Nu (e
} B!&5*f}*
} !td!">r46e
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CountControl.java 08ZvRy(Je<
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/* H>+/k-n-
* CountThread.java
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* vC,FE
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* Created on 2007年1月1日, 下午4:57 T, #-: }
* Vg$d|m${
* To change this template, choose Tools | Options and locate the template under C1-U2@
* the Source Creation and Management node. Right-click the template and choose :-x?g2MY
* Open. You can then make changes to the template in the Source Editor. a?-J j\q
*/ m'2F#{
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package com.tot.count; ["nWIs[h
import tot.db.DBUtils; !{l% 3'2
import java.sql.*; ?c8~VQaQ
/** dC6>&@
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* I!/EQO|
* @author O<vBuD2
*/ 9':Ipf&x
public class CountControl{ W1)SgiXnuy
private static long lastExecuteTime=0;//上次更新时间 0Jv6?7]LKa
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 (%R%UkwP9
/** Creates a new instance of CountThread */ $j- Fm:ZIA
public CountControl() {} X0j\nXk
public synchronized void executeUpdate(){ F>.y>h
Connection conn=null; v
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PreparedStatement ps=null; >"/TiQt
try{ s~,!E
conn = DBUtils.getConnection(); s$(%]~P
conn.setAutoCommit(false); yD<#Q\,
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); t3$ cX_
for(int i=0;i<CountCache.list.size();i++){ ytj});,>
CountBean cb=(CountBean)CountCache.list.getFirst(); 91z=ou
CountCache.list.removeFirst(); jZIT[HM
ps.setInt(1, cb.getCountId()); /[6wm1?!
ps.executeUpdate();⑴
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//ps.addBatch();⑵ S:!5|o|
} KLe6V+ki*
//int [] counts = ps.executeBatch();⑶ R V#w0 r
conn.commit(); 7b1
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}catch(Exception e){ :+YHj)mN
e.printStackTrace(); TD\TVK3P
} finally{ -,
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try{ ;*5z&1O
if(ps!=null) { Dml?.-Uv<
ps.clearParameters(); "pt[Nm76)8
ps.close(); ,q*|R
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ps=null; pRfKlTU\
} m&A bH&;
}catch(SQLException e){} Cnpl0rV~5
DBUtils.closeConnection(conn); 7UBW3{d/u5
} -F`gRAr-
} .x$V~t
public long getLast(){ A]"6/Lr9P
return lastExecuteTime; ,GWa3.&.d
} yMW3mx301j
public void run(){ -}@C9Ja[?
long now = System.currentTimeMillis(); O4-#)#-)S~
if ((now - lastExecuteTime) > executeSep) { xpa+R^D5G
//System.out.print("lastExecuteTime:"+lastExecuteTime); q!&:y7O8
//System.out.print(" now:"+now+"\n"); N_D=j6B
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); j &[lDlI_
lastExecuteTime=now; kX V
executeUpdate(); .NdsKhg
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} e`+
else{ 6 w!qZ4$
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ="T}mc
} -)J*(7F(6^
} ';eAaDM
} .dzw5R&
//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 5@.8O VPz
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类写好了,下面是在JSP中如下调用。 <> =(BAw
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<% qw4wg9w5p
CountBean cb=new CountBean(); wB 8548C}-
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); =YYqgNz+\w
CountCache.add(cb); Z+R-}<
out.print(CountCache.list.size()+"<br>"); lxTqGwx
CountControl c=new CountControl(); iMVQt1/
c.run(); "=?JIQ
out.print(CountCache.list.size()+"<br>"); 0Wd5s{S
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