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: dscgj5b1~
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CountBean.java YN,A)w:]
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/* G"6 !{4g
* CountData.java y^k$Us
* `gJ(0#ac
* Created on 2007年1月1日, 下午4:44 yr6V3],Tp
* ?CZd Ol
* To change this template, choose Tools | Options and locate the template under 0erNc'e
* the Source Creation and Management node. Right-click the template and choose y(&Ac[foS}
* Open. You can then make changes to the template in the Source Editor. G6/m#
*/ _&x%^&{
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package com.tot.count; <GJbmRc|
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/** dveiQ
* ~@!bsLSMU
* @author z{6Z
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*/ ?5p>BER?
public class CountBean { pw#-_
private String countType; ':q p05t
int countId; 4
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/** Creates a new instance of CountData */ i1085ztN
public CountBean() {} .d*8C,
public void setCountType(String countTypes){ @d_M@\r=j
this.countType=countTypes; Lr+$_ t}r
} wq{hF<
public void setCountId(int countIds){ _M1 %Z~
this.countId=countIds; NRuNKl.v
} /}$+uBgJm
public String getCountType(){ ~~.}ah/_d
return countType; ni<(K
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} 3R/bz0 V>
public int getCountId(){ [ )F<V!
return countId; rA1._
} y}
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} JT?h1v<H]
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CountCache.java =D(j)<9$A
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/* cNrg#Asen&
* CountCache.java +_!QSU,@
* jdN`mosJ
* Created on 2007年1月1日, 下午5:01 ^q&x7Kv%
* ;a/E42eN;
* To change this template, choose Tools | Options and locate the template under TC('H[
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* the Source Creation and Management node. Right-click the template and choose b>W%t
* Open. You can then make changes to the template in the Source Editor. hPh-+Hb
*/ "Q<MS'a
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package com.tot.count; =|=(l)8
import java.util.*; 0K+ne0I
/** 965jtn
* b>|6t~}M
* @author @~e5<:|5#
*/ _!6jR5&r,
public class CountCache { I]575\bA
public static LinkedList list=new LinkedList(); PCvWS.{
/** Creates a new instance of CountCache */ 3]>| i
public CountCache() {} Z;i:](
public static void add(CountBean cb){ \zY!qpX<
if(cb!=null){ [
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list.add(cb); QZs!{sZ
}
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} Ba,`TJ%y
} KXy6Eno
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CountControl.java hM{bavd
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/*
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* CountThread.java UZMd~|
* q'DW~!>qX
* Created on 2007年1月1日, 下午4:57 M7T5
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* 53D]3
* To change this template, choose Tools | Options and locate the template under %{|p j
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* the Source Creation and Management node. Right-click the template and choose &HW9Jn
* Open. You can then make changes to the template in the Source Editor. Za9qjBH
*/ paK2xX8E
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package com.tot.count; +2{Lh7Ks
import tot.db.DBUtils; vQCy\Gi
import java.sql.*; NOva'qk
/** =euni}7a
* nKY6[|!#
* @author yAt^;
*/ YWLj?+
public class CountControl{ <YY 14p
private static long lastExecuteTime=0;//上次更新时间 KPF1cJ2N
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 QV!up^Zso
/** Creates a new instance of CountThread */ fVlB=8DNk&
public CountControl() {} }tz7b#
public synchronized void executeUpdate(){ 0S"MC9beg
Connection conn=null; ;I}fBZ3
PreparedStatement ps=null; l**X^+=$
try{ se)TzI^]b@
conn = DBUtils.getConnection(); )e{aN+
conn.setAutoCommit(false); (zk"~Ud
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); aUp
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for(int i=0;i<CountCache.list.size();i++){ +[VXs~I
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CountBean cb=(CountBean)CountCache.list.getFirst(); iTwm3V
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CountCache.list.removeFirst(); 7I}uZ/N
ps.setInt(1, cb.getCountId()); Ac@VGT:9
ps.executeUpdate();⑴ occ7zcA
//ps.addBatch();⑵ 7! Nsm
} OXA7w.^
//int [] counts = ps.executeBatch();⑶ %EH)&k
conn.commit(); &
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}catch(Exception e){ gdc<ZYcM
e.printStackTrace(); l#o
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} finally{ >Tgv11[
try{ a(nlTMfu
if(ps!=null) { IxU/?Zm
ps.clearParameters(); sRs>"zAg
ps.close(); M%HU4pTW#o
ps=null; la!~\wpa
} lxx2H1([
}catch(SQLException e){} -n
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DBUtils.closeConnection(conn); Ui~>SN>s
} XS#Qu=,-
} uRvP hkqm
public long getLast(){ 6x`t{g]f,
return lastExecuteTime; pBHRa?Y5
} y(#e}z:
public void run(){ ftb\0,-
long now = System.currentTimeMillis(); )9g2D`a4
if ((now - lastExecuteTime) > executeSep) { Lbgi7|&
//System.out.print("lastExecuteTime:"+lastExecuteTime); V[LglPt
//System.out.print(" now:"+now+"\n"); >MZ/|`[M
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ytImB`'\
lastExecuteTime=now; oH@78D0A
executeUpdate(); Q &8-\
} @ArSC
else{ *dQSw)R
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); Gc?a +T
} /~1+i'7V.,
} %{W6PrY{
} dtDFoETz
//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 Wtnfa{gP%
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类写好了,下面是在JSP中如下调用。 vx
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<% /vt3>d%B;
CountBean cb=new CountBean(); 6tZI["\
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $nb[GV
CountCache.add(cb); w0.
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out.print(CountCache.list.size()+"<br>"); Eci\a]
CountControl c=new CountControl(); +A+)=/i;
c.run(); HS$r8`S?)
out.print(CountCache.list.size()+"<br>"); h[ ZN+M
%>