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:
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CountBean.java /[L)tj7B
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/* `
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* CountData.java hJ4S3b
* r?]%d!
* Created on 2007年1月1日, 下午4:44 #O><A&FrF`
* ]
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* To change this template, choose Tools | Options and locate the template under ~RCg.&[ou
* the Source Creation and Management node. Right-click the template and choose M0L-u
* Open. You can then make changes to the template in the Source Editor. A{t"M-<
*/ $&Ac5Zo%}
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package com.tot.count; k)Zn>
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/** 2gH_$
* m/KjJ"s,
* @author ,=x
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*/ ?}v}U^
public class CountBean { GGp{b>E+
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private String countType; 0hb/`[Q
int countId; cPm~`
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/** Creates a new instance of CountData */ >z5Oy
public CountBean() {} y78z>(jV
public void setCountType(String countTypes){ b<8q 92F
this.countType=countTypes; >07shNX
} >waN;&>/
public void setCountId(int countIds){ %/X2 l
this.countId=countIds; }oV3EIH
} M-vC>u3Y
public String getCountType(){ bbO+%-(X
return countType; wyNC|P;j$g
} =}"R5
public int getCountId(){ H[Cj7{V
return countId; 3 ^pYCK%
} :K:f^o]s
} s v6INe:
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CountCache.java vD_u[j]
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/* i5Eeg`NMl
* CountCache.java G}s;JJax
* e7h\(`J0lj
* Created on 2007年1月1日, 下午5:01 ?${V{=)*X'
* W.z$a.<(rF
* To change this template, choose Tools | Options and locate the template under fHLFeSfH
* the Source Creation and Management node. Right-click the template and choose aQxe)
* Open. You can then make changes to the template in the Source Editor. 7Onk!NH
*/ 3V"dG1?
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package com.tot.count; zv`zsqDJ
import java.util.*; CJ0$;et
/** nhp)yW
* n}+wd9J*!2
* @author ?-4OfGN
*/ k"0%' Y
public class CountCache { ]}_p3W "Y9
public static LinkedList list=new LinkedList(); @h!U
/** Creates a new instance of CountCache */ L,O>6~9:^1
public CountCache() {} ]X/O IfdWe
public static void add(CountBean cb){ vi^z5n
if(cb!=null){ 33O)k*g
list.add(cb); @Ap@m6K?q
} 8TUF w@H%
} i'U,S`L6>
} ;g&7*1E
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CountControl.java zI1(F67d`
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/*
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* CountThread.java O.]_Ry\OXA
* 3&O% &
* Created on 2007年1月1日, 下午4:57 }R4(B2vup
* m2jwqx{G
* To change this template, choose Tools | Options and locate the template under ~WzMK
* the Source Creation and Management node. Right-click the template and choose ~}epq6L>
* Open. You can then make changes to the template in the Source Editor. 3O #~dFnp
*/ GU2]/\W*a
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package com.tot.count; ^ b=5 6~[
import tot.db.DBUtils; EPQ&?[6
import java.sql.*; Dm&lSWW`/
/** e6Wl7&@6
* Ma% E&.ed
* @author D%6ir*%T
*/ 2=i+L z^
public class CountControl{ jn0t-":
private static long lastExecuteTime=0;//上次更新时间 c`rfKr&z
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 n iXHK$@5
/** Creates a new instance of CountThread */ <{3q{VW*
public CountControl() {} 7Ntjx(b$"h
public synchronized void executeUpdate(){ s$K@X `
Connection conn=null; FEge+`{,
PreparedStatement ps=null; 'SsPx&)l
try{ ~vO'p
conn = DBUtils.getConnection(); ZJ;wRd@
conn.setAutoCommit(false); -HO6K)ur
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @hE7r-}]
for(int i=0;i<CountCache.list.size();i++){ kxcgOjrmI
CountBean cb=(CountBean)CountCache.list.getFirst(); %Y#[%~|(
CountCache.list.removeFirst(); x&mz-
ps.setInt(1, cb.getCountId()); "Nk`RsW
ps.executeUpdate();⑴ x0}<n99qE
//ps.addBatch();⑵ |:!EHFr
} iuvtj]/
//int [] counts = ps.executeBatch();⑶ WiPM <'
conn.commit(); }Z~pfm_S
}catch(Exception e){ !~6'@UYo
e.printStackTrace(); z:0-aDeM
} finally{ $}^Rsv(
try{ m0dFA<5-
if(ps!=null) { KfJ c
ps.clearParameters(); 7vB9K _wCI
ps.close(); ctnAVm
ps=null; (:tTx>V#
} I^rZgp<'i
}catch(SQLException e){} 6)tB{:h&~0
DBUtils.closeConnection(conn); YzforM^F
} yHa:?u6
} FCS5@l,'<
public long getLast(){ U'f$YVc
return lastExecuteTime; 5$(b3]
} 'fp<FeTg
public void run(){ p,_6jdz
long now = System.currentTimeMillis(); T%N~oa
if ((now - lastExecuteTime) > executeSep) { \@iOnRuHn9
//System.out.print("lastExecuteTime:"+lastExecuteTime); "<g?x`iz
//System.out.print(" now:"+now+"\n"); -f-O2G=
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); t-?KKU8
lastExecuteTime=now; Z<$E.##
executeUpdate(); 8`R +y
} D}k-2RM2k
else{ 1{;[q3a
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); x
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} WrIL]kJw^
} 6Zl.Lh
} +73=2.C0
//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 =:ya;k&
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类写好了,下面是在JSP中如下调用。 ai<MsQQ:=
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<% 'p|Iwtjn>
CountBean cb=new CountBean(); URmAI8fq*M
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); mE3SiR "
CountCache.add(cb); O>tC]sm%
out.print(CountCache.list.size()+"<br>"); {GG~E54&B
CountControl c=new CountControl(); 0C"PC:h5
c.run(); 7Y_fF1-wY
out.print(CountCache.list.size()+"<br>"); O9Jx%tolF%
%>