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: }WkR-5N
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CountBean.java rUF= uO(
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/*
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* CountData.java 0j~C6vp
* T xwZ3E
* Created on 2007年1月1日, 下午4:44 a
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* Jqi^Z*PuX
* To change this template, choose Tools | Options and locate the template under [.iz<Yh
* the Source Creation and Management node. Right-click the template and choose i%_nH"h
* Open. You can then make changes to the template in the Source Editor. B8G1
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*/ au1(.(
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package com.tot.count; l7JY`x
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/** RnkrI~x
* ZgI1Byf
* @author '.DFyHsq
*/ bc|DC,n?
public class CountBean { G_x<2E"d
private String countType; 0l ]K%5#
int countId; )Wm:Ilq
/** Creates a new instance of CountData */ Q<pL5[00fD
public CountBean() {} h|1 /Q
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public void setCountType(String countTypes){ MkG*6A
this.countType=countTypes; 4h~o>(Sq
} i/UHDqZ
public void setCountId(int countIds){ Nu'T0LPNq(
this.countId=countIds; *<_8]C0>
} 3v%V\kO=F
public String getCountType(){ e'z[JG=
return countType; vN%SN>=L<
} Hh8)d/D
public int getCountId(){ LN?W~^gsR
return countId; 9q-9UC!g
} 5}4r'P$m:
} .pOTIRbA
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CountCache.java W`^Zb[
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/* 64>o3Hb2
* CountCache.java Q0_UBm^f
* >\ :kP>U
* Created on 2007年1月1日, 下午5:01 PI#xRKt
* -Ug
* To change this template, choose Tools | Options and locate the template under <OcD [5
* the Source Creation and Management node. Right-click the template and choose $!x8XpR8s
* Open. You can then make changes to the template in the Source Editor. h+!Ld^'c
*/ I7hE(2!$
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package com.tot.count; VMUK|pC4K
import java.util.*; r-+ .Ax4L"
/** ~g+?]Lk}
* jLf. qf8qm
* @author ^xO
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*/ ;k<g#She
public class CountCache { &oTUj'$
public static LinkedList list=new LinkedList(); ! 3O#'CV
/** Creates a new instance of CountCache */ '@h5j6:2
public CountCache() {} PG8|w[V1 "
public static void add(CountBean cb){ 3EN?{T<yf
if(cb!=null){ f YR*B0tu
list.add(cb); i*' 6"
} t3.;W/0_
} |~Hlv^6H
} pzP~,cdf
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CountControl.java WUSkN;idVG
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/* 18 pi3i[
* CountThread.java {1.t ZCMT
* Re**)3#gn
* Created on 2007年1月1日, 下午4:57 vd>X4e^j
* F'DO46
* To change this template, choose Tools | Options and locate the template under j_VTa/
* the Source Creation and Management node. Right-click the template and choose hmv"|1Sa!~
* Open. You can then make changes to the template in the Source Editor. (-tF=wR,W
*/ ,c#=qb8""
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package com.tot.count; GtRc7,
import tot.db.DBUtils; 4i>sOP3
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import java.sql.*; j'#M'W3@
/** /(Se:jH$>
* wiXdb[[#
* @author vq|o}6Et
*/ u/3 4E=
public class CountControl{ c0.i
private static long lastExecuteTime=0;//上次更新时间 $IzhaX
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 48JD >=@7
/** Creates a new instance of CountThread */ y#Je%tAe
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public CountControl() {} fX=o,=-f
public synchronized void executeUpdate(){ C~IsYdln
Connection conn=null; FMCX->}$
PreparedStatement ps=null; ;q&6WO
try{ bLyU;
conn = DBUtils.getConnection(); v`ckvl)(C
conn.setAutoCommit(false); ^W|B Xxo
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); E? 1"&D
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for(int i=0;i<CountCache.list.size();i++){ ;v0M
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CountBean cb=(CountBean)CountCache.list.getFirst(); 7/nnl0u8
CountCache.list.removeFirst(); .'QE o
ps.setInt(1, cb.getCountId()); ],l
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ps.executeUpdate();⑴ #?/&H;n_8S
//ps.addBatch();⑵ m%Ah]x;
} &eYnO~$!
//int [] counts = ps.executeBatch();⑶ 5 Z+2
conn.commit();
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}catch(Exception e){ R0dIxG%
e.printStackTrace(); `NqX{26GV+
} finally{ &VG|*&M
try{ es}j6A1
if(ps!=null) { Y0`@$d&n
ps.clearParameters(); #w\Bc\
ps.close(); egcJ@Of
ps=null; "iFA&$\
} Id`?yt
}catch(SQLException e){} : tKa1vL
DBUtils.closeConnection(conn); 6% +s`
} DA'A-C2
} Hgs=qH
public long getLast(){ ,MkldCV
return lastExecuteTime; u2=gG.
} m/W0vPM1
public void run(){ n3w(zB
long now = System.currentTimeMillis(); Q"UWh~
if ((now - lastExecuteTime) > executeSep) { 6")co9
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6- H81y3
//System.out.print(" now:"+now+"\n"); OnGtIY
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); r?Y+TtF\e
lastExecuteTime=now; fNz*E|]8&
executeUpdate(); o(iv=(o
} 5r1{l%?
else{ TE+d?
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1eG@?~G
} {4u8~whLp
} 7bBOV(/s
} c-S_{~~
//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 &%YFO'>>}
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类写好了,下面是在JSP中如下调用。 slSQ \;CDA
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<% 8ut:cCrmg
CountBean cb=new CountBean(); C:C9swik"5
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ['F,
CountCache.add(cb); I{Pny/d`
out.print(CountCache.list.size()+"<br>"); 3wRk -sl
CountControl c=new CountControl(); -OLXR c=
c.run(); *ml&}9
out.print(CountCache.list.size()+"<br>"); .:eNL]2%:
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