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: it]im
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CountBean.java abiZ"?(
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/* t80s(e
* CountData.java _5TSI'@.4
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* Created on 2007年1月1日, 下午4:44 HT&CbEa4'
* <=.0
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* To change this template, choose Tools | Options and locate the template under Pyh+HD\
* the Source Creation and Management node. Right-click the template and choose \7rAQ[\#V
* Open. You can then make changes to the template in the Source Editor. .nN=M>#/
*/ X`i'U7%I
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package com.tot.count; iUSP+iC,
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/** 0K/Pth"*
* S_; 5mb+b
* @author oSVo~F
*/ I5]=\k($
public class CountBean { 1o"/5T:S[
private String countType; K$v
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int countId; rEz-\jLD~
/** Creates a new instance of CountData */ +8qtFog$\g
public CountBean() {} o6`4y^Q{/
public void setCountType(String countTypes){ 'a.n
this.countType=countTypes; )9/.K'o,dy
} p3tu_If
public void setCountId(int countIds){ h OYm
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this.countId=countIds; 9R_2>BDn
} 9/A$3#wF
public String getCountType(){ 5=/&[=
return countType; /`(Kbwh
} 0XouHU
public int getCountId(){ UNLmnj;-Q
return countId; X3[gi`
} W\]bh'(
} ;R[ xo!
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CountCache.java |OW/-&)
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/* #I>
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* CountCache.java YywiY).]@
* cr GFU?8
* Created on 2007年1月1日, 下午5:01 +*u'vt?
* 590.mCm
* To change this template, choose Tools | Options and locate the template under &gF*p
* the Source Creation and Management node. Right-click the template and choose m]H[$Q
* Open. You can then make changes to the template in the Source Editor. OAigq6[,
*/ Zop3[-
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package com.tot.count; A8,9^cQ]
import java.util.*; M)v\7a
/** ++ O
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* OJ#ehw <
* @author j,<3[
*/ W,sU5sjA
public class CountCache { D5]AL5=Xt2
public static LinkedList list=new LinkedList(); -64@}Ts*?
/** Creates a new instance of CountCache */ /<[S> ;!kr
public CountCache() {} &6]+a4
public static void add(CountBean cb){ '?| (QU:)F
if(cb!=null){ ? :StFlie
list.add(cb); +_^Rxx!XA
} ggluQGA
} l^`& Tnzv
} `Fn"%P!
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CountControl.java x"g-okLN
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/* ~nit~;
* CountThread.java `As|MYv
* D$X9xtT
* Created on 2007年1月1日, 下午4:57 7
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* un*Ptc2%
* To change this template, choose Tools | Options and locate the template under (pBPf
* the Source Creation and Management node. Right-click the template and choose jbQ N<`!
* Open. You can then make changes to the template in the Source Editor. XKp$v']u
*/ 2Y~UeJ_\Lq
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package com.tot.count; TcB^Sctf
import tot.db.DBUtils; -Iq
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import java.sql.*; ~bm
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/** _(J;!,
* T,'{0q
* @author GCrIaZ
*/ 1zo0/<dk
public class CountControl{ 3C:!\R
private static long lastExecuteTime=0;//上次更新时间 ^3>Qf
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MHF31/g\
/** Creates a new instance of CountThread */ Z|78>0SAt
public CountControl() {} rbC4/ 9G\
public synchronized void executeUpdate(){ !T+jb\O_
Connection conn=null; cL+--$L
PreparedStatement ps=null; Mn)>G36(
try{ Oup5LH!sW
conn = DBUtils.getConnection(); p#14
conn.setAutoCommit(false); bxxazsj^
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ';H"Ye:D=7
for(int i=0;i<CountCache.list.size();i++){ O
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CountBean cb=(CountBean)CountCache.list.getFirst(); r'TxYM-R
CountCache.list.removeFirst(); [_$r- FA
ps.setInt(1, cb.getCountId()); :eK(9o
ps.executeUpdate();⑴ l ~bjNhk
//ps.addBatch();⑵ )7X+T'?%
} |AosZeO_
//int [] counts = ps.executeBatch();⑶ ~Onj|w7
conn.commit(); 72i]`
}catch(Exception e){ -|1H-[Y(
e.printStackTrace(); w@K4u{|
} finally{ W|~Jl7hs8Q
try{ #=}dv8
if(ps!=null) { =O~ J
ps.clearParameters(); sObH#/l`
ps.close(); 7z.(pg=
ps=null; O~p@87aq
} }"$2F0
}catch(SQLException e){} A~2U9f+\
DBUtils.closeConnection(conn); t>f61<27eB
} FWi c/7
} g&79?h4UXQ
public long getLast(){ t h!$R
return lastExecuteTime; bHJKX>@{
} M-#OPj*
public void run(){ Lg;b17
long now = System.currentTimeMillis(); Y 6NoNc]h
if ((now - lastExecuteTime) > executeSep) { UU7E+4O&
//System.out.print("lastExecuteTime:"+lastExecuteTime); "-y2En
//System.out.print(" now:"+now+"\n"); cpIFjb>u{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); p3m!Iota
lastExecuteTime=now; Ou26QoT9XI
executeUpdate(); Gky
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} EnM }H9A
else{ 9S<87sO
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); FJ/>=2^B
} Z$UPLg3=;_
} bCV3h3<
} TO(2n8'fdO
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 MC
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类写好了,下面是在JSP中如下调用。 'ycr/E&m{
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<% t)#dR._q
CountBean cb=new CountBean(); 9/8#e+L
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); +*I'!)T^B
CountCache.add(cb); uTWij4)a
out.print(CountCache.list.size()+"<br>"); y v$@i A
CountControl c=new CountControl(); |8QXjzH
c.run(); 2H,^i,
out.print(CountCache.list.size()+"<br>"); sIVVF#0}]
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