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: r=Lgh#9S
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CountBean.java OQ?N_zs,
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/* msfE;
* CountData.java 9+N%Io?!
* EXVZ?NG
* Created on 2007年1月1日, 下午4:44 llX `
* ?%Nh4+3N>
* To change this template, choose Tools | Options and locate the template under [tfB*m5
* the Source Creation and Management node. Right-click the template and choose ~BJE~
* Open. You can then make changes to the template in the Source Editor. Pm/i,T6&\
*/ *{fs{gFw9
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package com.tot.count; |w{Qwf!2
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/** ~KMah
* E;C{i
* @author j`RG Moq
*/ *qO)MpG{
public class CountBean { 0,ryy,2
private String countType; =ejU(1 g
int countId; TQ4L~8
/** Creates a new instance of CountData */ Ri" hU/H{
public CountBean() {} lNg){3
public void setCountType(String countTypes){ LiT%d
this.countType=countTypes; A2M(
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} =#W:z.w
public void setCountId(int countIds){ -9= DDoO
this.countId=countIds; OriYt
} jj]\]6@+P
public String getCountType(){ ;n(f?RO3X
return countType; Fk 3(( n=
} P%e7c,
public int getCountId(){ rn*'[i?
return countId; ,*6K3/kW
} l|gi2~ %Y
} mXyP;k
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CountCache.java \M\7k5$
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/* $ -1ajSVJ
* CountCache.java ye$_=KARP
* kpn|C 9r
* Created on 2007年1月1日, 下午5:01 9Tt%~m^
* pK3A/ry<
* To change this template, choose Tools | Options and locate the template under @y;VV*
* the Source Creation and Management node. Right-click the template and choose .@OQ$D <
* Open. You can then make changes to the template in the Source Editor. Pa3-0dUr
*/ !9/`PcNIpy
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package com.tot.count; <>\|hno}
import java.util.*; `Fr ,,Q81\
/** -GPBX?
* )x/#sW%)
* @author ;(`bP
*/ d0I s|Gs
public class CountCache {
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public static LinkedList list=new LinkedList(); ?{f6su@rW
/** Creates a new instance of CountCache */ o1(;"5MM
public CountCache() {} t(*n[7e
public static void add(CountBean cb){ %[*-aA
if(cb!=null){ 0@zJa;z'
list.add(cb); ?(=|!`IoO
} :gwmk9LZ
} KZ7B2
} M+
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CountControl.java ]z^jz#>um&
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/* 1 gjaTPwY
* CountThread.java %@a;q?/?Nd
* %MHL@Nn>e
* Created on 2007年1月1日, 下午4:57 BNdq=|,+"
* U U_0@V<
* To change this template, choose Tools | Options and locate the template under /=6_2t#vA
* the Source Creation and Management node. Right-click the template and choose qco'neR"z
* Open. You can then make changes to the template in the Source Editor. # atq7tX
*/ Ly2,*\7
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package com.tot.count; 1sj7]G]`k
import tot.db.DBUtils; $mM"C+dD
import java.sql.*; x&;AY
/** $mGzJ4&
* 2PSExK57
* @author j
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*/ &EV%g6
public class CountControl{ WS n>P7sY
private static long lastExecuteTime=0;//上次更新时间 1iz =i^}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 _9lMa7i
/** Creates a new instance of CountThread */ {"Sv~L|J;
public CountControl() {} \UK}B
public synchronized void executeUpdate(){ ]gPx%c
Connection conn=null; -&2Z/qM&!
PreparedStatement ps=null; #1J,!seJ
try{ lot`6]
conn = DBUtils.getConnection(); @
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conn.setAutoCommit(false); RG45S0Ygj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); lF(v<drkB
for(int i=0;i<CountCache.list.size();i++){ }XBF#BN
CountBean cb=(CountBean)CountCache.list.getFirst(); Qt4mg?X/
CountCache.list.removeFirst(); I*a@_EO
ps.setInt(1, cb.getCountId()); #(614-r/
ps.executeUpdate();⑴ ?fy37m(M}
//ps.addBatch();⑵ /Kli C\
} md{nHX&
//int [] counts = ps.executeBatch();⑶ K@1gK<,a
conn.commit(); ENhLonMeV
}catch(Exception e){ n}Z%D-b$
e.printStackTrace(); [ ft6xI
} finally{ akbB=:M,x
try{ ^x O](,H
if(ps!=null) { ^ou)c/68aQ
ps.clearParameters(); >WLX5i&
ps.close(); NHyUHFY
ps=null; Jp"29
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} h<&GdK2U+
}catch(SQLException e){} 4Px|:7~wT8
DBUtils.closeConnection(conn); )Q`Ycz-
} =a,qRO
} N:U}b1$L6
public long getLast(){ s&nat4{B
return lastExecuteTime; =p.avAuSn
} FA-cTF[,(
public void run(){ K]$PRg1|3
long now = System.currentTimeMillis(); ||X3g"2W9
if ((now - lastExecuteTime) > executeSep) { kBk>1jn"
//System.out.print("lastExecuteTime:"+lastExecuteTime);
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//System.out.print(" now:"+now+"\n"); l3b=8yn.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); h!SsIy(
lastExecuteTime=now; u
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executeUpdate(); 'M6+(`x
} ri4z^1\
else{ "|(.W3f1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m@kLZimD
} "W+>?u )
} >C_G~R
} 3mU~G}ig
//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 hev;M)t
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类写好了,下面是在JSP中如下调用。 i=<;$+tW
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<% bEcN_7
CountBean cb=new CountBean(); *ilh/Hd>
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); )I*(yUj
CountCache.add(cb); eV}" L:bgJ
out.print(CountCache.list.size()+"<br>"); nQV0I"f]?]
CountControl c=new CountControl(); $#f_p-N
c.run(); 1#3|PA#>
out.print(CountCache.list.size()+"<br>"); 6ZE`'pk<
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