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: GP(nb,
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CountBean.java k5|GN Y6a
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/* $3S`A]xO
* CountData.java {Ia1Wd 8n
* G b4p"3
* Created on 2007年1月1日, 下午4:44 J'%W_?wZ
* ,z01*Yx
* To change this template, choose Tools | Options and locate the template under x21XzGLY|}
* the Source Creation and Management node. Right-click the template and choose GMY[Gd
* Open. You can then make changes to the template in the Source Editor. <Zo{D |hW
*/ n0FzDQt26
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package com.tot.count; _n0NE0
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/** b"2_EnE}1
* IC6'>2'=T
* @author ;*{Ls#
*/ SAU` u]E
public class CountBean { NE><(02qW
private String countType; ` Nv1sA#C
int countId; QBCEDv&j
/** Creates a new instance of CountData */ kZ0z]Y
public CountBean() {} Ekn3ODz,
public void setCountType(String countTypes){ ? r}2JHvN
this.countType=countTypes; YB_fy8Tfx
} dtBr#Te
public void setCountId(int countIds){ fRwr}n'
this.countId=countIds; ~uG/F?= Q:
} q#F+^)DD [
public String getCountType(){ hT%
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return countType; VHLt,?G
} yuhY )T
public int getCountId(){ ey$H2zmo
return countId; ^e]h\G
} DB0?H+8t
} I :8s 3;
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CountCache.java P\h1%a/D
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/* 7e[&hea
* CountCache.java RJ-J/NhWyI
* &srD7v9M8
* Created on 2007年1月1日, 下午5:01 psuK\s
* ky'G/z
* To change this template, choose Tools | Options and locate the template under lm*C:e)4A
* the Source Creation and Management node. Right-click the template and choose ./<giTR:p
* Open. You can then make changes to the template in the Source Editor. NAO0b5-h
*/ 5^{ I}Q
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package com.tot.count; hP_{$c{4:g
import java.util.*; i&-g
/** _z\qtl~3
* `,Fc271`
* @author /Ri-iC >
*/ T#KVN{O
public class CountCache { ~ymSsoD^
public static LinkedList list=new LinkedList(); J&L#^f*d
/** Creates a new instance of CountCache */ 9R:?vk4
public CountCache() {} a_zf*;
public static void add(CountBean cb){ <.ZD.u
if(cb!=null){ Z^ .qX\<M
list.add(cb); (rQ)0g@
}
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} !>WW(n07Ma
} bV:MOj^
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CountControl.java KDr)'gl&
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/* k;<F33v;Mh
* CountThread.java xv7nChB
* XvZ5Q
* Created on 2007年1月1日, 下午4:57 wsj5;(f+
* )o;n2T#O
* To change this template, choose Tools | Options and locate the template under F<O<=Ww
* the Source Creation and Management node. Right-click the template and choose =%{E^z>1
* Open. You can then make changes to the template in the Source Editor. SJlL!<i$
*/ XcKyrh;i
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package com.tot.count; Hiih$O+
import tot.db.DBUtils; 9 LUk[V
import java.sql.*; +WvW#wpH
/** 7'7o^>
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* ?Hbi[YD
* @author j?(@x>HA
*/ ,U fB{BW
public class CountControl{ -];Hb'M.!e
private static long lastExecuteTime=0;//上次更新时间 h:
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 E6xWo)`%5s
/** Creates a new instance of CountThread */ Oe0dC9H
public CountControl() {} (Li)@Cn%
public synchronized void executeUpdate(){ OQ _wsAA
Connection conn=null; 3ZqtIQY`
PreparedStatement ps=null; nz`"f,
try{ D[(T--LLT
conn = DBUtils.getConnection(); [ZETyM`
conn.setAutoCommit(false); (N{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,-.=]r/s
for(int i=0;i<CountCache.list.size();i++){ )J&!>GP
CountBean cb=(CountBean)CountCache.list.getFirst(); {#l@9r%
CountCache.list.removeFirst(); $]b&3_O$N8
ps.setInt(1, cb.getCountId()); CM+wkU ?,
ps.executeUpdate();⑴ BgwZZ<B
//ps.addBatch();⑵ pXe]hnY
} tmC9p6%
//int [] counts = ps.executeBatch();⑶ &uJ7[m19z
conn.commit(); _LLE~nUK"/
}catch(Exception e){ yF1^/y!@
e.printStackTrace(); WhL1OG
} finally{ a; 0$fRy
try{ 9R|B 5.
if(ps!=null) { @"`{Sh`Y$
ps.clearParameters(); hF-X8$[
ps.close(); Y0nuwX*{
ps=null; SFa^$w
} jqy?Od)
}catch(SQLException e){} N-GQ\&
DBUtils.closeConnection(conn); [mQ*];GA
} ^Cn_
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} 7h.:XlUm|
public long getLast(){ }u~r.=
return lastExecuteTime; y{\(|j
} }{e7wqS$&,
public void run(){ +isaqfy/
long now = System.currentTimeMillis(); ]TKM.[[
if ((now - lastExecuteTime) > executeSep) { kN$L8U8f
//System.out.print("lastExecuteTime:"+lastExecuteTime); H @8 ;6D
//System.out.print(" now:"+now+"\n"); o#F0 3
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /J'dG%
lastExecuteTime=now; A\<WnG>xjP
executeUpdate(); *!+?%e{;b
} fpvzx{2
else{ <txzKpM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 5$f*fMd;
} HltURTbI
} ,_yf5 a
} N%`Eq@5
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 h2edA#bub
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类写好了,下面是在JSP中如下调用。 610hw376B
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<% !yX4#J(
CountBean cb=new CountBean(); pmi`Er
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mH09*
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CountCache.add(cb); K\>CXa
out.print(CountCache.list.size()+"<br>"); ic|>JX$G
CountControl c=new CountControl(); }g[(h=Qi
c.run(); [+v}V ,jb
out.print(CountCache.list.size()+"<br>"); D`uOBEX
%>