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: ;,Q6AS!
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CountBean.java *m9,_~t
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/* (v$$`zh
* CountData.java s2M|ni=
* {rWFgn4Li
* Created on 2007年1月1日, 下午4:44 h!UB#-
* /ng+IC3
* To change this template, choose Tools | Options and locate the template under Q^z&;%q1
* the Source Creation and Management node. Right-click the template and choose "8YXFg
* Open. You can then make changes to the template in the Source Editor. ]eD5It\
*/ ;yVT:qd
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package com.tot.count; ~Y /55uC
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/** hY-;Vh0J
* Nw=mSW^E
* @author "f-z3kL
*/ 2h^9lrQcQG
public class CountBean { H&3i[D!p
private String countType; {9yW8&m
int countId; Z2wgfP`
/** Creates a new instance of CountData */ A3=$I&!%
public CountBean() {} t:<dirw,o
public void setCountType(String countTypes){ >7^i>si
this.countType=countTypes; [r"`rBw
} ~Q/G_^U:
public void setCountId(int countIds){ tW#=St0<.o
this.countId=countIds; j/Rm~!q
} ZQQ0}
public String getCountType(){ f}U@e0Lsb
return countType; % HK \
} "G,$Sqi@
public int getCountId(){ MEZc/Ru-[
return countId; @5y ~A}Vd
} hJcN*2\:
} 5gnmRd
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CountCache.java P-c<[DSM'I
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/* [#hoW"'Q9
* CountCache.java F4%vEn\!
* 5v@-.p
* Created on 2007年1月1日, 下午5:01 jaq`A'o5
* K=`;D
* To change this template, choose Tools | Options and locate the template under bPHqZ*f
* the Source Creation and Management node. Right-click the template and choose $pOgFA1'
* Open. You can then make changes to the template in the Source Editor. +bv-! rf
*/ Ar:ezA
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package com.tot.count; -g;cg7O#(
import java.util.*; Z(=UZI?
/** t@1bu$y
* zjVQ \L
* @author !04zWYHo
*/ y Ddi+
public class CountCache { E6FT*}Q
public static LinkedList list=new LinkedList();
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/** Creates a new instance of CountCache */ ejuw+@ _
public CountCache() {} k_}aiHdG
public static void add(CountBean cb){ Im* ~6[
if(cb!=null){ %]15=7#'y
list.add(cb); 5/>W(,5}
}
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} *tD`X(K
} {zf)im[.
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CountControl.java YrWC\HR_
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/* &/7D4!N]
* CountThread.java ;[~:Y[N
* ZLRAiL
* Created on 2007年1月1日, 下午4:57 a7Fc"s*
* 6]*~!al?
* To change this template, choose Tools | Options and locate the template under ueM[&:g&MU
* the Source Creation and Management node. Right-click the template and choose }&{z-/;H
* Open. You can then make changes to the template in the Source Editor. I3wv6xZ2
*/ w6 x{<d
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package com.tot.count; :Vyr8+]
import tot.db.DBUtils; kA1C&
import java.sql.*; Pfv| K;3i
/** ^bjaa
* =oPc\VYW
* @author IV5B5Q'D
*/
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public class CountControl{ >P/Nb]C
private static long lastExecuteTime=0;//上次更新时间 1 ynjDin<
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ."#M
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/** Creates a new instance of CountThread */ ief~*:5
public CountControl() {} Fu%%:3_
public synchronized void executeUpdate(){ ]U8VU
Connection conn=null; b+ g(=z+
PreparedStatement ps=null; %di]1vQ
try{ =h<LlI^v
conn = DBUtils.getConnection(); v_$'!i$
conn.setAutoCommit(false); 4CT _MAj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); > (.V(]{3y
for(int i=0;i<CountCache.list.size();i++){ L
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CountBean cb=(CountBean)CountCache.list.getFirst(); 8a;I,DK=j
CountCache.list.removeFirst(); w>q:&Q
ps.setInt(1, cb.getCountId()); Q0\tK=Z/
ps.executeUpdate();⑴ d,R
//ps.addBatch();⑵ W=9Zl(2C
} ~baVS-v
//int [] counts = ps.executeBatch();⑶ L:(>ON
conn.commit(); tL;!!vg#V
}catch(Exception e){ LXm5f;
e.printStackTrace(); d\R]>
} finally{ w!=Fi
try{ p? dXs^ c
if(ps!=null) { I,:R~^qJ8v
ps.clearParameters(); G q" [5r"
ps.close(); R6N+c\W
ps=null; FccT@,.F
} 6U`<+[K7
}catch(SQLException e){} d0;$k,
DBUtils.closeConnection(conn); |"Rl_+d7D
} b"t<B2N
} H)Zb _>iV
public long getLast(){ g@<E0
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return lastExecuteTime; bHi0N@W!vG
} 4K(AXk
public void run(){ z/,qQVv=}4
long now = System.currentTimeMillis(); 1ud+~y$K
if ((now - lastExecuteTime) > executeSep) { =ca<..yh[d
//System.out.print("lastExecuteTime:"+lastExecuteTime); WI?iz-,](
//System.out.print(" now:"+now+"\n"); 7I,/uv?
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); F>0[v|LG
lastExecuteTime=now;
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executeUpdate(); h#o3qY
} ~_z"So'|F_
else{ nJvDk h#h1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Jf/X3\0N7
} XM+o e0:[
} I.M@we/bR}
} b* QRd
//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 /%#LA
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类写好了,下面是在JSP中如下调用。 #DN5S#Ic
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<% Q
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CountBean cb=new CountBean(); m5G9
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); T JB)]d<
CountCache.add(cb); {G+pI2^
out.print(CountCache.list.size()+"<br>"); O%g%*9
CountControl c=new CountControl(); X/
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c.run(); $ON4nx
out.print(CountCache.list.size()+"<br>"); abHW[VP9
%>