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: ht5eb"c+8
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CountBean.java W=ar&O~}n
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/* :8 jaW?~
* CountData.java *\T
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* ]q<Zc>OC
* Created on 2007年1月1日, 下午4:44 mQqv{1
* $G.ws
* To change this template, choose Tools | Options and locate the template under a@}A;y'd
* the Source Creation and Management node. Right-click the template and choose Z0Df~ @
* Open. You can then make changes to the template in the Source Editor. t%Hy#z1W_
*/ ! C|VX,w
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package com.tot.count; \'.#of
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/** \aB>Q"pS
* ,+hH|$
* @author RT$.r5l_@
*/ A0`#n|(Ad!
public class CountBean { LJ+Qe%|
private String countType; [(PD2GO+
int countId; +*vg)F:
/** Creates a new instance of CountData */ b$k|D)_|
public CountBean() {} DU=rsePWE
public void setCountType(String countTypes){ y8|?J\eRy
this.countType=countTypes; qt{{q
} Q{"QpVY8
public void setCountId(int countIds){ QfHO3Y6h[
this.countId=countIds; E"[h20`\/
} sfwlv^
public String getCountType(){ L]ce13K
return countType; hA!kkNqV
} SFQYrY
public int getCountId(){ Hd9vS"TN]
return countId; **!
} mf\eg`'4?
} %
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CountCache.java 2qkZ B0[
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/* 3HI-G.]hC
* CountCache.java jt? .g'
* gvl3NQQ%t
* Created on 2007年1月1日, 下午5:01 MzudCMF
* a][QY1E@?
* To change this template, choose Tools | Options and locate the template under t/`~(0F
* the Source Creation and Management node. Right-click the template and choose cN(Toj'`
* Open. You can then make changes to the template in the Source Editor. )%T<Mw2u
*/ s%c>Ge
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package com.tot.count; cEc_S42Z
import java.util.*; ;ZVT[gi*
/** !CO1I-yL
* GL<u#[
* @author SWpvbs.'so
*/ 6-oy%OnN
public class CountCache { 2MQ
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public static LinkedList list=new LinkedList(); Tb@r@j:V
/** Creates a new instance of CountCache */ 8nSEAr~
public CountCache() {} ]dj
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public static void add(CountBean cb){ jqeR{yo&0b
if(cb!=null){ xS>d$)rIj
list.add(cb); h]{V/
} i3[%]_eP.
} >&g^ `
} v+b#8
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CountControl.java N9}27T+4
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/* jr`;H
* CountThread.java ^
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* 1](PuQm7+
* Created on 2007年1月1日, 下午4:57 h%*@82DKK
* Z,Z4Sp
* To change this template, choose Tools | Options and locate the template under $]`rWSYtv`
* the Source Creation and Management node. Right-click the template and choose RNMd,?dj
* Open. You can then make changes to the template in the Source Editor. 5z~O3QX
*/ r\."=l
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package com.tot.count; 0`y*7.Ip
import tot.db.DBUtils; +~[>Usf
import java.sql.*; u"s@eN
/** d"0=.sA
* <<M1:1
* @author W_bp~Wu
*/ @yj$
public class CountControl{ L}M%z9K`h
private static long lastExecuteTime=0;//上次更新时间 aT_%G&.
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 &)ED||r,
/** Creates a new instance of CountThread */ w =2; QJ<
public CountControl() {} vBLs88
public synchronized void executeUpdate(){ #i'wDvhol
Connection conn=null; !(8)'<t9
PreparedStatement ps=null; qvC 2BQ
try{ F6Ne?[b
conn = DBUtils.getConnection(); f>zd,|)At
conn.setAutoCommit(false); Is[n7Q
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @=NTr
for(int i=0;i<CountCache.list.size();i++){ n3"
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CountBean cb=(CountBean)CountCache.list.getFirst(); "%rzL.</
CountCache.list.removeFirst(); 'TO/i:{\
ps.setInt(1, cb.getCountId()); lKBI3oYn
ps.executeUpdate();⑴ E@J}(76VS
//ps.addBatch();⑵ 9
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} .$U=ngj\t
//int [] counts = ps.executeBatch();⑶ OD6dMql
conn.commit(); u$rSM0CJ
}catch(Exception e){ $[U:Dk}
e.printStackTrace(); 9WT{~PGj
} finally{ Xk?Y
try{ r*kz`cJ
if(ps!=null) { f64}#E|w
ps.clearParameters(); kIJ=]wU|v
ps.close(); ;-quK%VO!
ps=null; #}+_Hy
} vs2xx`Y<Lq
}catch(SQLException e){} PnJA'@x
DBUtils.closeConnection(conn); < c[dpK5c
} "~aCW~
} m'ykDK\B
public long getLast(){ y3pr(w9A
return lastExecuteTime; "P{T]
} Wf:I
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public void run(){ \F8*HPM=*
long now = System.currentTimeMillis(); %)G]rta#
if ((now - lastExecuteTime) > executeSep) { 3bPF+(`J
//System.out.print("lastExecuteTime:"+lastExecuteTime); 9Sk?tl
//System.out.print(" now:"+now+"\n"); 4O'X+dv^I
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 1U< g
lastExecuteTime=now;
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executeUpdate(); cQldBc
} h` ,! p
else{ (
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//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); ({#M*=&"
} 6zJfsKf$
} "8h7"WR
} iLD:}yK
//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 yZ]u{LJS
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类写好了,下面是在JSP中如下调用。 by8~'?
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<% &?gvW//L2
CountBean cb=new CountBean(); "iY=1F"\R
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); \,5OPSB
CountCache.add(cb); c})f&Z@<
out.print(CountCache.list.size()+"<br>"); mh=YrDU+L
CountControl c=new CountControl(); 1y($h<
c.run(); !*@sX7H
out.print(CountCache.list.size()+"<br>"); wio}<Y6Xz
%>