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: C\hM =%
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CountBean.java h'nY3GrU
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/* v4 E}D
* CountData.java j3ls3H&
* 0jWVp-y
* Created on 2007年1月1日, 下午4:44 Bk{]g=DO
* vtJJ#8a]
* To change this template, choose Tools | Options and locate the template under k4zZ7H
* the Source Creation and Management node. Right-click the template and choose gI|~|-'
* Open. You can then make changes to the template in the Source Editor. =($xG#g`
*/ ,|/f`Pl
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package com.tot.count; YtLt*Ig%
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/** Q\0'lQJdy
* E' uZA
* @author */S_Icf
*/ Ab;.5O$y
public class CountBean { NvX[zqNP_R
private String countType; E _|<jy$`
int countId; <IW$m!{VG
/** Creates a new instance of CountData */ @IZnFHN
public CountBean() {} ~pky@O#b
public void setCountType(String countTypes){ uCB=u[]y4
this.countType=countTypes; ;722\y(Y
} ;-Aa|aT!
public void setCountId(int countIds){ %J-GKpo/S
this.countId=countIds; >y+B
} f*
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public String getCountType(){ fI|$K)K
return countType; p5*jzQ
} 4?01s-Y
public int getCountId(){ L-&\\{X
return countId; _,*r_D61S
} KqP#6^ _
} 4Wp=y
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CountCache.java bcz:q/f}@
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/* oxtay7fx
* CountCache.java F((4U"
* _)iCa3z
* Created on 2007年1月1日, 下午5:01 An0GPhC
* yaX
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* To change this template, choose Tools | Options and locate the template under cm+P]8o%{
* the Source Creation and Management node. Right-click the template and choose i"=\d
* Open. You can then make changes to the template in the Source Editor. b7ZSPXV
*/ NwfVL4Xg
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package com.tot.count; PQE=D0
import java.util.*; DVeE1Q
/** 2B`JGFcdcB
* #lO Mm9
* @author `EQL" =)
*/ !bP@n
public class CountCache {
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public static LinkedList list=new LinkedList(); TkF[x%o
/** Creates a new instance of CountCache */ z0Z%m@
public CountCache() {} MWh6]gGs
public static void add(CountBean cb){ W}ofAkF
if(cb!=null){ -tU'yKhn
list.add(cb); ?&uu[y
} /zox$p$?h
} `
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} {2gwk8
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CountControl.java :~SyL !
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/* _(zG?]y0P
* CountThread.java G KeU%x
* 4 H&#q>
* Created on 2007年1月1日, 下午4:57 DW3G
* og>uj>H&
* To change this template, choose Tools | Options and locate the template under f,Ghb~y
* the Source Creation and Management node. Right-click the template and choose O&hTNIfi
* Open. You can then make changes to the template in the Source Editor. e~(5%CO>#j
*/ -7|H}!DFT
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package com.tot.count; 7PF%76TO
import tot.db.DBUtils; 51.%;aY~z
import java.sql.*; 5E
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/** :fJN->wY^s
* /Gfw8g\}
* @author q0\6F^;M
*/ Zgb!E]V[
public class CountControl{ P+HXn8@
private static long lastExecuteTime=0;//上次更新时间 'we>q@
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 >C~6\L`c
/** Creates a new instance of CountThread */ bQ5\ ]5M
public CountControl() {} Ht&YC<X
public synchronized void executeUpdate(){ -%4,@
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Connection conn=null; @[v~y"tE}
PreparedStatement ps=null; ,wPr"U+7
try{ ~bpgSP"
conn = DBUtils.getConnection(); r@,2E6xn
conn.setAutoCommit(false); ]]Ufas9
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); %N_%JK\{@
for(int i=0;i<CountCache.list.size();i++){ {f p[BF
CountBean cb=(CountBean)CountCache.list.getFirst(); ^dxTm1Z
CountCache.list.removeFirst(); Wn}'bqp
ps.setInt(1, cb.getCountId()); Vf1^4t
ps.executeUpdate();⑴ Dum9lj
//ps.addBatch();⑵ N4HqLh23H
} @|T'0_'
//int [] counts = ps.executeBatch();⑶ Z$? #
conn.commit(); ^d73Ig:8q
}catch(Exception e){ HkVB80hv
e.printStackTrace(); +qdEq_m
} finally{ An/|+r\
try{ >c}u>]D
if(ps!=null) { AkiDL=;w
ps.clearParameters(); .5{ab\_af
ps.close(); =H]@n|$(
ps=null; 2I{"XB
} pI<f) r
}catch(SQLException e){} l}M!8:UzU
DBUtils.closeConnection(conn); 1yY0dOoLG)
} S`Rs82>
} [=`q>|;pOv
public long getLast(){ J9S>yLQK
return lastExecuteTime; 6D_D' ;o
} o3}3p]S\
public void run(){ }SCM I4\
long now = System.currentTimeMillis(); )}O8?d`
if ((now - lastExecuteTime) > executeSep) { w@fi{H(R
//System.out.print("lastExecuteTime:"+lastExecuteTime); ( &x['IR
//System.out.print(" now:"+now+"\n"); bi;1s'Y<D
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); g<
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lastExecuteTime=now; 13/]DF,S"^
executeUpdate(); P{^6v=8)
} o#1 $q`Z
else{ Eu04e N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); seeBS/%
} El"Q'(:/U
} LBP`hK:>W~
} ?=pT7M
//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 Yc*;/T}
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类写好了,下面是在JSP中如下调用。 BTrn0
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<% 8DaL,bi*.
CountBean cb=new CountBean(); ^sWT:BDh
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); o2\8OxcA
CountCache.add(cb); R@rBEW&
out.print(CountCache.list.size()+"<br>"); d m%8K6|
CountControl c=new CountControl(); E8&TO~"a]e
c.run(); ,
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out.print(CountCache.list.size()+"<br>"); ufT`"i
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