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: v4,Dt
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CountBean.java FzG>iC}
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/* EKEJ9Y+47H
* CountData.java 'i4L.&
* cVDcda|PE
* Created on 2007年1月1日, 下午4:44 bP&1tE
* N t\ZM
* To change this template, choose Tools | Options and locate the template under VPb8dv(a3
* the Source Creation and Management node. Right-click the template and choose Qw<&N$
* Open. You can then make changes to the template in the Source Editor. LHSbc!Y'.
*/ ;?%_jB$P
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package com.tot.count; 9^@)R
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/** o_03Io
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* \susLD
* @author wYQEm
*/ R$;TX^r'o&
public class CountBean { )T^xDx
private String countType; i:1
@ vo
int countId; zpZfsn!
/** Creates a new instance of CountData */ \} _,g
public CountBean() {} -B?cF9
public void setCountType(String countTypes){ aP#/%
this.countType=countTypes; Q"H/RMo-
} L2OR<3*|Av
public void setCountId(int countIds){ J M`[|"R%
this.countId=countIds; Rx?ze(
} I
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public String getCountType(){ my#\(E+
return countType; R[@}Lg7+v
} X!m
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public int getCountId(){ ],Yy)<e.
return countId; /@I`V?Q!a
} 6"R'z#{OF
} >T-4!ZvS\j
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CountCache.java `\f 3Ij,
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/* cZ# %tT#
* CountCache.java F6aC'<#/
* KtGbpcS$f
* Created on 2007年1月1日, 下午5:01 !;0K=~(Y^
* l2I%$|)d
* To change this template, choose Tools | Options and locate the template under SYa
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* the Source Creation and Management node. Right-click the template and choose %`YR+J/V
* Open. You can then make changes to the template in the Source Editor. [2E(3`-u
*/ h`iOs>
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package com.tot.count; F<XOt3VY.
import java.util.*; QWtDZ>
/** (e0(GOqf4
* KC)}Mzt6_
* @author r-.>3J
*/ YrV@k*O*
public class CountCache { d</F6aM\
public static LinkedList list=new LinkedList(); nv\K!wZI=b
/** Creates a new instance of CountCache */ Qqs1%u;e8
public CountCache() {} pTXF^:8
public static void add(CountBean cb){ A0:rn\$l3
if(cb!=null){ W#=,FZT
list.add(cb); W1EYVXN
} N1B$z3E*
} 9Vo*AK'&U
} Keem\/
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CountControl.java SMzq,?-`
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/* <'N:K@Cs
* CountThread.java </u=<^ire
* *QV"o{V
* Created on 2007年1月1日, 下午4:57 ambr}+}
* ,Vw>3|C
* To change this template, choose Tools | Options and locate the template under hS&l4 \I'Z
* the Source Creation and Management node. Right-click the template and choose ,~DV0#"
* Open. You can then make changes to the template in the Source Editor. ZvMU3])u
*/ _54gqD2C,
}
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package com.tot.count; LD1&8kJ*l
import tot.db.DBUtils; cnI5G!
import java.sql.*; @bJIN]R
/** ^39lUKL
* : ^("L,AF
* @author M:b#">M
*/ 8;r #HtFM
public class CountControl{ *0to,$ n
private static long lastExecuteTime=0;//上次更新时间 i;-M8Q^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 v?Utz~lQ
/** Creates a new instance of CountThread */ gu+zfvkcY
public CountControl() {} Y~e)3e
public synchronized void executeUpdate(){ <f M}Kk
Connection conn=null; Fm,` ]CO
PreparedStatement ps=null; `j(._`8%a
try{ @Z2np{X:
conn = DBUtils.getConnection(); Gx6%Z$2n
conn.setAutoCommit(false); zRou~Kxi
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); o+7)cI
for(int i=0;i<CountCache.list.size();i++){ -*z7`]5J
CountBean cb=(CountBean)CountCache.list.getFirst(); Jv+w{"&
CountCache.list.removeFirst(); Fx|`0LI+C
ps.setInt(1, cb.getCountId()); ][
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ps.executeUpdate();⑴ R TpNxr{[
//ps.addBatch();⑵ ;81,1
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} q\~
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//int [] counts = ps.executeBatch();⑶ -z0;4O (K]
conn.commit(); iER@_?
}catch(Exception e){ tH44\~
e.printStackTrace(); >6HGh#0(p
} finally{ a4*976~![
try{ p6R+t]oH
if(ps!=null) { /s}
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ps.clearParameters(); {(!JYz~P
ps.close(); 1l"2 ~k
ps=null; kDMvTVd
} d?T!)w
}catch(SQLException e){} b5LToy:
DBUtils.closeConnection(conn); q\]X1N
} }cr'o"4
} J E7m5kTa
public long getLast(){ f?51sr
return lastExecuteTime; dGn0-l'q
} :C(/yg
public void run(){ #[bL9R5NC
long now = System.currentTimeMillis(); }#7rg_O]>
if ((now - lastExecuteTime) > executeSep) { yV )fJ_
//System.out.print("lastExecuteTime:"+lastExecuteTime); .Zv~a&GE
//System.out.print(" now:"+now+"\n"); nqm=snh
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Z$JJ0X
lastExecuteTime=now; _X~O6e-!
executeUpdate(); (8)9S6
} BEvY&3%l
else{ ?'z/S5&j
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CV.|~K0O
} &h5Y_no GX
} Xt<1b
} lz~^*\ F
//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 %DYh<U4N
"(7y%TFt:
类写好了,下面是在JSP中如下调用。
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<% T\uIXL?3
CountBean cb=new CountBean(); 7I
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); j2<+[h-
CountCache.add(cb); wW1VOj=6V"
out.print(CountCache.list.size()+"<br>"); {zvaZY|K"
CountControl c=new CountControl(); m^}|LB:5
c.run(); Cl<!S`
out.print(CountCache.list.size()+"<br>"); 3HpqMz
%>