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: gL/9/b4
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CountBean.java F#5~M<`.o
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/* /PXzwP_(A
* CountData.java G7/ +ogV
* 1<aP92/N&
* Created on 2007年1月1日, 下午4:44 g2Z`zQA7
* }3WxZv]I}
* To change this template, choose Tools | Options and locate the template under aV0"~5
* the Source Creation and Management node. Right-click the template and choose ]\HvK CN}
* Open. You can then make changes to the template in the Source Editor. /&JT~M
*/ s_p!43\J
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package com.tot.count; [AJJSd/:
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/** :e+jU5;]3
* <<O$ G7c
* @author *wjrR1#81x
*/ -M#Wt`6A
public class CountBean { ZXPX,~ 5o
private String countType; C\hM =%
int countId; o.`5D%}i
/** Creates a new instance of CountData */ sU^1wB
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public CountBean() {} (+hK%}K>
public void setCountType(String countTypes){ KD.]i' d<
this.countType=countTypes; y$M%2mh`
} =:U`k0rn!
public void setCountId(int countIds){ +:/%3}`
this.countId=countIds; :7;@ZEe
} H3oFORh
public String getCountType(){ "_?nN"A7
return countType; pEz_qy[#
} _+3::j~;m
public int getCountId(){ 0JujesUw(
return countId; Zx>=tx}
} \o3gKoL%
} S$-7SEkO+
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CountCache.java ?:9"X$XR
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/* *|HY>U.
* CountCache.java eS){1
*
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* Created on 2007年1月1日, 下午5:01 E=O\0!F|b
* J]r^W)O
* To change this template, choose Tools | Options and locate the template under bpa?C
* the Source Creation and Management node. Right-click the template and choose 3=V&K-
* Open. You can then make changes to the template in the Source Editor. 'dc#F3
*/ 1Ai^cf:S
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package com.tot.count; cso8xq|b7
import java.util.*; tfWS)y7
/** dlnX_+((KC
* /G`]=@~
* @author ZWm6eD
*/ `XDl_E+>l
public class CountCache { M869MDo
public static LinkedList list=new LinkedList(); *qpSXmOz
/** Creates a new instance of CountCache */ M )(DZ}
public CountCache() {} oxtay7fx
public static void add(CountBean cb){ F((4U"
if(cb!=null){ _)iCa3z
list.add(cb); An0GPhC
} yaX
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} cm+P]8o%{
} i"=\d
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CountControl.java NwfVL4Xg
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/* pQQH)`J|t
* CountThread.java gnHbb-<i,
* 2B`JGFcdcB
* Created on 2007年1月1日, 下午4:57 #lO Mm9
* f%8C!W]Dm
* To change this template, choose Tools | Options and locate the template under "ocyK}l.?
* the Source Creation and Management node. Right-click the template and choose zKK9r~ M
* Open. You can then make changes to the template in the Source Editor. b~cZS[S
*/ l%=;
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package com.tot.count; V]?R>qhgu
import tot.db.DBUtils; l}P=/#</T
import java.sql.*; u$`a7Lp,n
/** lk =<A"^S
* !PE]C!*gv&
* @author 1AFA=t:]p
*/ NCD04U5y
public class CountControl{ dgP3@`YS
private static long lastExecuteTime=0;//上次更新时间 #p{4^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 c[s4EUG
/** Creates a new instance of CountThread */ (w zQ2Dk
public CountControl() {} ?r!o~|9|
public synchronized void executeUpdate(){ [<TrS/,)>
Connection conn=null; '0,^6'VWOV
PreparedStatement ps=null; CNx8]
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try{ &,)&%Sg[
conn = DBUtils.getConnection(); A/?7w
conn.setAutoCommit(false); c4z R*
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); 3r1*m
+
for(int i=0;i<CountCache.list.size();i++){ ,tRj4mx
CountBean cb=(CountBean)CountCache.list.getFirst(); fd9k?,zM
CountCache.list.removeFirst(); L\iFNT}g`
ps.setInt(1, cb.getCountId()); 7mfS*aCb
ps.executeUpdate();⑴ 'E.w=7z&
//ps.addBatch();⑵ f<6lf7qzC
} /<BI46B\
//int [] counts = ps.executeBatch();⑶ *n"{J(Jt`
conn.commit(); d0 /#nz
}catch(Exception e){ ll?X@S
e.printStackTrace(); (Awm9|.{+
} finally{ G]aOHJ:.
try{ kvj#c
if(ps!=null) { U`s{Jm
ps.clearParameters(); W(/h Vt
ps.close(); HLi%%"'
ps=null; XB5DPx
} \.}c9*)
}catch(SQLException e){} 9MqGIOQ${j
DBUtils.closeConnection(conn); NyuQMU
} 7>*vI7O0l
} Vf1^4t
public long getLast(){ Dum9lj
return lastExecuteTime; N4HqLh23H
} @|T'0_'
public void run(){ Z$? #
long now = System.currentTimeMillis(); ^d73Ig:8q
if ((now - lastExecuteTime) > executeSep) { kAGBdaJ"
//System.out.print("lastExecuteTime:"+lastExecuteTime); Jfl!#UAD|n
//System.out.print(" now:"+now+"\n"); +qdEq_m
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 3T0"" !Q
lastExecuteTime=now; j_7mNIr
executeUpdate(); t.C5+^+%
} <
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else{ {+ b7sA3
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p{dj~ &v
} B#1;r-^P<
} IEvdV6{K
} Jj%K=sw
//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 ""~ajy
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类写好了,下面是在JSP中如下调用。 Ny)X+2Ae
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<% DLNbo2C
CountBean cb=new CountBean(); jb!i$/%w
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ZqO^f*F>h
CountCache.add(cb); 18:%~>.!
out.print(CountCache.list.size()+"<br>"); 0+b1vhQ
CountControl c=new CountControl(); FHI ;)wn=
c.run(); ENY+^7
out.print(CountCache.list.size()+"<br>"); cj5+NM"
%>