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: r0F_;
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CountBean.java O6yP
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/* 7w "sJ
* CountData.java r_Lu~y|
* 0jBKCu
* Created on 2007年1月1日, 下午4:44 3YR *
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* n}19?K]g
* To change this template, choose Tools | Options and locate the template under mT96]V\
* the Source Creation and Management node. Right-click the template and choose #hIEEkCp +
* Open. You can then make changes to the template in the Source Editor. A?e,U,
*/ A&N$tH
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package com.tot.count; T3=(`
#`/bQ~s
/** mv{<'
* M9gOoYf,~
* @author FIH@2zA
*/ Gc wt7~
public class CountBean { (I[s3EnhS
private String countType; 19'5Re&
int countId; f6Ml[!aU
/** Creates a new instance of CountData */ ThtMRB)9
public CountBean() {} mxgqS=`
public void setCountType(String countTypes){ -!l^]MU
this.countType=countTypes; Q |%-9^
} YV-j/U{&
public void setCountId(int countIds){ [O\9 9>
this.countId=countIds; sJOV2#r
} 0 <g{ V
public String getCountType(){ }B`Ku5 M
return countType; $(3uOsy
} *#zS^b n
public int getCountId(){ JRXRi*@
return countId; 6(Vhtr2(*
} 8fh4%#,C%
} 6AAswz'$P
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CountCache.java +Juh:1H
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/* 4^[
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* CountCache.java `;$h'eI9
* /D'M 24
* Created on 2007年1月1日, 下午5:01 ywOmQcZ
* _lX8K:C(
* To change this template, choose Tools | Options and locate the template under nM8[
* the Source Creation and Management node. Right-click the template and choose 5rloK"
* Open. You can then make changes to the template in the Source Editor. -%,"iaO
*/ i'=2Y9S}
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package com.tot.count; s7l23*Czl
import java.util.*; +P)ys#=
/** R&*@@F-dx
* bY)#v?
* @author Zj!Abji=O
*/ h&`y$Jj
public class CountCache { DW>ES/B8$(
public static LinkedList list=new LinkedList(); :IZ"D40m"
/** Creates a new instance of CountCache */ G?xJv`"9iC
public CountCache() {} o_$&XNC_
public static void add(CountBean cb){ s$ z2 c
if(cb!=null){ Hhl-E:"H`
list.add(cb); to>
} Skxd<gv
} (` c
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} 2w?hgNz
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CountControl.java T$mbk3P
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/* t,<UohL|z
* CountThread.java x)oRSsv!Tr
* "HK/u(z)
* Created on 2007年1月1日, 下午4:57 1m)M;^_
* v* ~3Z1
* To change this template, choose Tools | Options and locate the template under N'?u1P4G
* the Source Creation and Management node. Right-click the template and choose /{*$JF
* Open. You can then make changes to the template in the Source Editor. L;/n!k.A
*/ eV2mMSY
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package com.tot.count; D*2\{W/
import tot.db.DBUtils; +@:L|uFU
import java.sql.*; 8ObeiVXf)
/** ea9oakF
* )(TAT<
* @author N+g@8Q2s;5
*/ /+[63=fl
public class CountControl{ 4XJiIa?
private static long lastExecuteTime=0;//上次更新时间 "rNL
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 NX,-;v
/** Creates a new instance of CountThread */ Vw~\H Gs/~
public CountControl() {} m;,xmEp
public synchronized void executeUpdate(){ a9Y5
Connection conn=null; fZ{[]dn[
PreparedStatement ps=null; 1cC1*c0Z
try{ ^}$O|t
conn = DBUtils.getConnection(); K7(MD1tk
conn.setAutoCommit(false); f.xA_Y>
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); }NCL>l;q
for(int i=0;i<CountCache.list.size();i++){ 3z8C
CountBean cb=(CountBean)CountCache.list.getFirst(); w0J|u'H
CountCache.list.removeFirst(); eJ@~o{,?>
ps.setInt(1, cb.getCountId()); #R&H&1
ps.executeUpdate();⑴ p]T"|! d
//ps.addBatch();⑵ {/8Q)2*>0
} u8L$]vOg
//int [] counts = ps.executeBatch();⑶ KZ:hKY@q
conn.commit(); s0"e'
}catch(Exception e){ T.:+3:8|F
e.printStackTrace(); G|
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} finally{ ~)]} 91p
try{ +OHGn;C
if(ps!=null) { z\!K<d"Xv
ps.clearParameters(); #JW+~FU`
ps.close(); S4o$t-9l
ps=null; H)(jh
} Gc,_v3\
}catch(SQLException e){} 8y2+$
DBUtils.closeConnection(conn); ]uh3R{a/
} Z;DCI-Wg
} ,<Kx{+ [h
public long getLast(){ <[~,uR7
return lastExecuteTime; {MBTP;{*~
} ^+|De}`u
public void run(){ 1NLg _UBOK
long now = System.currentTimeMillis(); e":G*2a
if ((now - lastExecuteTime) > executeSep) { zTm]AG|0
//System.out.print("lastExecuteTime:"+lastExecuteTime); %&<LNEiUN
//System.out.print(" now:"+now+"\n"); @'2m$a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); hGTV;eU
lastExecuteTime=now; E,[xUz"
executeUpdate(); Lxl_"kG
} 0Q9T3X
else{ ef"?|sn
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); sy5 Fn~\R
} `)$_YZq|SR
} Wd,a?31|
} |UUdz_i!:
//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 ))h6~1`
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类写好了,下面是在JSP中如下调用。 ed!>)Cb
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<% GIwh@4;
CountBean cb=new CountBean(); >!6JKL~=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7 A$B{
CountCache.add(cb); 4Ft1@
out.print(CountCache.list.size()+"<br>"); :Ixx<9c.
CountControl c=new CountControl(); y(jg#7)
c.run(); VyLH"cCv
out.print(CountCache.list.size()+"<br>"); D@ek9ARAq
%>