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: g?Jx99c;
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CountBean.java 9a4Xf%!F>z
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/* =/_tQR~
* CountData.java dS9L( &
* B5FRe'UC
* Created on 2007年1月1日, 下午4:44 `+Ko{rf+9
* +\r=/""DW
* To change this template, choose Tools | Options and locate the template under ~ti{na4W<
* the Source Creation and Management node. Right-click the template and choose JQSp2b@'H
* Open. You can then make changes to the template in the Source Editor. 7&ty!PpD
*/ A}K2"lQ#>,
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package com.tot.count; -44{b<:D
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/** zT_
* l]:nncpns
* @author 2|2'?
*/ kY e3A&J
public class CountBean { !aylrJJ
private String countType; ?;{d
int countId; >\J({/ #O
/** Creates a new instance of CountData */ O+ ].'
public CountBean() {} Pr|:nJs
public void setCountType(String countTypes){ d"h*yH@
this.countType=countTypes; CJ'pZ]\G
} 53vnON#{*
public void setCountId(int countIds){ .&|Ivz6
this.countId=countIds; Id_?
} yWsJa)e3*@
public String getCountType(){ *CsRO
return countType; bU3e*Er
} /3( a'o[
public int getCountId(){ cu)ssT
return countId; u;-_%?
} 0f"9wPC
} 99xs5!4s
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CountCache.java SEf:u
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/* <m") 2dJ
* CountCache.java ?\_\pa/+
* H);O. m
* Created on 2007年1月1日, 下午5:01 EMe3Xb
`
* . \/jy]Y
* To change this template, choose Tools | Options and locate the template under OC(S"&D
* the Source Creation and Management node. Right-click the template and choose 12W`7
* Open. You can then make changes to the template in the Source Editor. W Z!?O0.A
*/ .Oh4b5
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package com.tot.count; B;[ai?@c(_
import java.util.*; EL--?<g
/** ]f%yeD
* LYYz =gvZl
* @author =IbDGw(
*/ (Nzup3j
public class CountCache { b#h}g>l
public static LinkedList list=new LinkedList(); ~Bw)rf,
/** Creates a new instance of CountCache */ Rv-`6eyAA
public CountCache() {} %Y0,ww2
public static void add(CountBean cb){ HNFG:t9
if(cb!=null){ 6bv~E.
list.add(cb); R&lJ& SgC
} UG@9X/l}
} olHT* mr
} ]6:|-x:m
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CountControl.java CxvL!ew
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/* @e`%'
* CountThread.java REEs}88);'
* FabDK :
* Created on 2007年1月1日, 下午4:57 {Kbb4%P+h
* %MA o<,ha
* To change this template, choose Tools | Options and locate the template under 5X4 #T&.
* the Source Creation and Management node. Right-click the template and choose V*}xlxSL
* Open. You can then make changes to the template in the Source Editor. pJnT \~o
*/ CrvL[6i
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package com.tot.count; \B72 #NR
import tot.db.DBUtils; .dbZ;`s
import java.sql.*; %S'gDCwq
/** 0@O:C::
* >g {w,
* @author ( o(, ;
*/ }jfOs(Q]
public class CountControl{ ,sa%u Fm
private static long lastExecuteTime=0;//上次更新时间 -[h2fqu1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 <`PW4zSI
/** Creates a new instance of CountThread */ #![9QUvcf
public CountControl() {} *VP-fyJp
public synchronized void executeUpdate(){ sf7~hN*
Connection conn=null; Fj_6jsDb
PreparedStatement ps=null; )U2cS\k'7n
try{ K@RE-K6{
conn = DBUtils.getConnection(); %oee x1`=
conn.setAutoCommit(false); yF [|dB
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); @k|V4
for(int i=0;i<CountCache.list.size();i++){ 55%j$f
CountBean cb=(CountBean)CountCache.list.getFirst(); >+/2g
CountCache.list.removeFirst(); WLO4P
ps.setInt(1, cb.getCountId()); e$vvm bK.
ps.executeUpdate();⑴ 4~s{zob
//ps.addBatch();⑵ :kQ%Mj>
} ?KB+2]7m6
//int [] counts = ps.executeBatch();⑶ uG\ @e'pr
conn.commit(); Ro2Ab^rQ|
}catch(Exception e){ 006qj.
e.printStackTrace(); 6bE~m<B\`
} finally{ EuJ_UxkG
try{ O4 +a[82
if(ps!=null) { P(Gv|Q@
ps.clearParameters(); uQ(C,f[6p
ps.close(); # $N)
ps=null; uV|%idC
} /QgU!:e
}catch(SQLException e){} 1M={8}3
DBUtils.closeConnection(conn); qV7F=1k]
} pHftz-RS!
} 7NFRCCXHQ
public long getLast(){ X2[d15!9
return lastExecuteTime; -ff@W m
} ><HHO
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public void run(){ )j_Y9`R
long now = System.currentTimeMillis(); (#)-IdXXO<
if ((now - lastExecuteTime) > executeSep) { ,E._A(Z
//System.out.print("lastExecuteTime:"+lastExecuteTime); \>G :mMk/
//System.out.print(" now:"+now+"\n"); 0#/N ZO
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); U!TSAg21P
lastExecuteTime=now; E! s?amM4
executeUpdate(); R(1N]>
} rL KwuZ
else{ ~43T$^<w;
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); `[(.Q
} .='hYe.
} dlf nhf
} _rN1(=J
//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 <N~&Leh
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类写好了,下面是在JSP中如下调用。 [_X.Equ
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<% s(?A=JJ
CountBean cb=new CountBean(); c %f'rj
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); v PJ=~*P=
CountCache.add(cb); 1y{@fg~..
out.print(CountCache.list.size()+"<br>"); y@'~fI!E4
CountControl c=new CountControl(); ir?Y>
c.run(); =qNZ7>Qw
out.print(CountCache.list.size()+"<br>"); o9JZ-biH
%>