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: T0g0jr{
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CountBean.java n.@#rBKZ
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/* z|uOJ0uK
* CountData.java ]n~yp5Nbr
* eUYZxe :6
* Created on 2007年1月1日, 下午4:44 P=2wkzeJj
* w(/7Jt$
* To change this template, choose Tools | Options and locate the template under _jW>dU^B
* the Source Creation and Management node. Right-click the template and choose yXkt:O,i
* Open. You can then make changes to the template in the Source Editor. I[@ts!YD
*/ ?vvG)nW
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package com.tot.count; Bu&So|@TL
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/** >xZ5ac
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* d60c$?"]a(
* @author Qr<AV:
*/ ^,LtEwd~Y
public class CountBean { I<sfN'FpT
private String countType; TFo}\B7
int countId; )GK+
/** Creates a new instance of CountData */ !-7_ +v>
public CountBean() {} \]t]#D>0
public void setCountType(String countTypes){ 5~QhX22
this.countType=countTypes; tbg*_ZQO u
} 3eWJt\}?B
public void setCountId(int countIds){ 2H6:np|O
this.countId=countIds; \/n+j!
} 7vw;Egd@@-
public String getCountType(){ ~)_K"h.DY
return countType; Cc2MYm8
} :Pc(DfkS
public int getCountId(){ 3+e4e
return countId; 5PDSA*
} ,}KwP*:Z
} |hc\jb
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CountCache.java [O(m/
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/* M%3Wy"YQ,n
* CountCache.java GKCM|Y
* 55^tfu
* Created on 2007年1月1日, 下午5:01 >:A<"wZ
* ![
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* To change this template, choose Tools | Options and locate the template under Y|_O8[
* the Source Creation and Management node. Right-click the template and choose 7N|
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* Open. You can then make changes to the template in the Source Editor. pzi q0
*/ RB IOdz
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package com.tot.count; !W~QT}
import java.util.*; X{`1:c'x
/** Oo1ecbY
* (#If1[L
* @author UoHd -
*/ oXdel
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public class CountCache { =MxpH+spI
public static LinkedList list=new LinkedList(); j|mv+O
/** Creates a new instance of CountCache */ !3@{U@*Z]
public CountCache() {} v$;@0t:;#
public static void add(CountBean cb){ Je 31".
if(cb!=null){ Od-Ax+Hp
list.add(cb); WtVf wC_
} fgmSgG"b
} Dm^l?Z
} #~S>K3(
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CountControl.java @`S.@^%7fO
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/* iy}xICt
* CountThread.java Q(e{~
]*
* _$5@uL{n"^
* Created on 2007年1月1日, 下午4:57 `w+1C&>^[
* J0sGvj{
* To change this template, choose Tools | Options and locate the template under YQYX,b
* the Source Creation and Management node. Right-click the template and choose 6A?8tm/0
* Open. You can then make changes to the template in the Source Editor. F\-Si!~oOz
*/ lov%V*tL
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package com.tot.count; r%|A$=[Q
import tot.db.DBUtils; xG1?F_]
import java.sql.*; I|T7+{5z
/** l!:^6i
* lm*g Gy1i
* @author 2T?TM! \Q
*/ zqf[Z3
public class CountControl{ )b0];&hw]
private static long lastExecuteTime=0;//上次更新时间 :v)6gz(p
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 A?r^V2+j
/** Creates a new instance of CountThread */ KUFz:&wK
public CountControl() {} GyK(Vb"h6
public synchronized void executeUpdate(){ [,b)YjO~Xd
Connection conn=null; |z*>ixK
PreparedStatement ps=null; ,56;4)cv
try{ W-m"@<Z
conn = DBUtils.getConnection(); "mA1H]r3
conn.setAutoCommit(false); V&iS~V0.
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); En\Z#0,V
for(int i=0;i<CountCache.list.size();i++){ AG>\aV"b
CountBean cb=(CountBean)CountCache.list.getFirst(); 9@'4P
CountCache.list.removeFirst(); P,ydt
ps.setInt(1, cb.getCountId()); 2M&$Wuu.q
ps.executeUpdate();⑴ (:7a&2/M
//ps.addBatch();⑵ 9go))&`PJL
} Y[um|M315
//int [] counts = ps.executeBatch();⑶ x*q35K^PE
conn.commit(); D5L{T+}Oi%
}catch(Exception e){ QNpuTZn#Q
e.printStackTrace(); d.AC%&W
} finally{ F 7LiG9H6`
try{ J@Yj\9U
if(ps!=null) { 4K7{f+T
ps.clearParameters(); #&BS
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ps.close(); niz 'b]] +
ps=null; wE6A
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} X~L!e}Rz
}catch(SQLException e){} (w$'o*z;(
DBUtils.closeConnection(conn); H+x#gK2l
} cmDT
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} +`}o,z/^
public long getLast(){ N2FbrfNFa
return lastExecuteTime; ;s_"{f`Y6
} iRve)
public void run(){ ix*muVBj.
long now = System.currentTimeMillis(); tvpN/p
if ((now - lastExecuteTime) > executeSep) { x7$ax79ly
//System.out.print("lastExecuteTime:"+lastExecuteTime); [.&[<!,.
//System.out.print(" now:"+now+"\n"); $.8 H>c
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); C:j]43`
lastExecuteTime=now; Yt{&rPv,
executeUpdate(); Y;_T=L
} -Qb0:]sV#
else{ =/}X$,@2
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); X<euD9?
} "~\*If
} ,g|2NjUAc
} 2Y+:,ud\
//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 S>t>6&A
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类写好了,下面是在JSP中如下调用。 nzuF]vo
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<% Pa&4)OD
CountBean cb=new CountBean(); UA(;fZ@
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); m~>@BCn;
CountCache.add(cb); mH\@QdF
out.print(CountCache.list.size()+"<br>"); zP nC=h|g
CountControl c=new CountControl(); |GuEGmR
c.run(); 2f..sNz
out.print(CountCache.list.size()+"<br>"); '5rUe\k
%>