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: 2o5<nGn
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CountBean.java
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/* z4+6k-#):
* CountData.java <ORz`^27o
* =F-^RnO%\
* Created on 2007年1月1日, 下午4:44 -6 Si
* j/IZm)\
* To change this template, choose Tools | Options and locate the template under P87Fg
* the Source Creation and Management node. Right-click the template and choose *TI6Z$b|6
* Open. You can then make changes to the template in the Source Editor. D>^ix[:J
*/ ")gCA:1-
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package com.tot.count; VCtiZ4
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/** eQIi}\`
* RSeezP6#
* @author H 6<@
*/ >-+X;0&
public class CountBean { rbS=Ewk
private String countType; !D5`8
int countId; 0x/V1?gm
/** Creates a new instance of CountData */ &WU*cfJn)A
public CountBean() {} %4^/.) Q
public void setCountType(String countTypes){ rAdcMFW
this.countType=countTypes; 7B2Og{P
} 54j
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public void setCountId(int countIds){ d>-EtWd
this.countId=countIds; z2zp c^i
} rzj'!~>U
public String getCountType(){ >c>ar>4xF
return countType; M_)T=s *
} vt=S0X^$yc
public int getCountId(){ LMzYsXG*[
return countId; "G)?
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} e(5R8ud
} _)"
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CountCache.java 3yX^R^`
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/* bFXCaD!{G
* CountCache.java 8rNxd=!
* b4PK
* Created on 2007年1月1日, 下午5:01 Tj+WO6#V
* Gukq}ZQ d
* To change this template, choose Tools | Options and locate the template under u[qtuM?&
* the Source Creation and Management node. Right-click the template and choose 0evZg@JP`
* Open. You can then make changes to the template in the Source Editor. -e\kIK
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*/ 4Lb<#e13R?
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package com.tot.count; HWZ*Htr
import java.util.*; {IwYoR aXa
/** []^>QsS(X
* (o=iX,@'2
* @author 4D$E
*/ *~X\c Z
public class CountCache { Ob+c*@KiW
public static LinkedList list=new LinkedList(); K_.x(Z(;4
/** Creates a new instance of CountCache */ (dZ&Af
public CountCache() {} #2=3 0
public static void add(CountBean cb){ C`K/ai{4
if(cb!=null){ zg"ZXZ
list.add(cb); 0CYI,V
} $OuA<-
} O-Y E6u
} @#">~P|Hp
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CountControl.java Iqv
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/* >cLZP#^\2E
* CountThread.java h2K
* *i90[3l
* Created on 2007年1月1日, 下午4:57 c5u?\
* =p:6u_@XWj
* To change this template, choose Tools | Options and locate the template under >MLqOUr#
* the Source Creation and Management node. Right-click the template and choose tzPe*|m<
* Open. You can then make changes to the template in the Source Editor. Hqv(X=6E0
*/ [c~zO+x
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package com.tot.count; :l{-UkbB
import tot.db.DBUtils; #,C{?0!
import java.sql.*; c-{]H8$v
/** ymu# u
* r v>6k:(
* @author :PJjy6,1
*/ nAOId90wue
public class CountControl{ g}7%3D
private static long lastExecuteTime=0;//上次更新时间 +(T,d ]o]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 dfce/QOV
/** Creates a new instance of CountThread */ EY(4<;)
public CountControl() {} 0jMrL\>C
public synchronized void executeUpdate(){ oizoKwp%
Connection conn=null; Dc5XU3Eu`
PreparedStatement ps=null; s RB8 jY
try{ _1QNO#X
conn = DBUtils.getConnection(); >FO=ioNY
conn.setAutoCommit(false); C_o.d~xm
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); HH+XEM P/g
for(int i=0;i<CountCache.list.size();i++){ $@X,J2&
CountBean cb=(CountBean)CountCache.list.getFirst(); z841g `:C
CountCache.list.removeFirst(); [a2/`ywdV
ps.setInt(1, cb.getCountId()); }z6HxB]$
ps.executeUpdate();⑴ L;;x%>
//ps.addBatch();⑵ ,KWeW^z'7
} [;}c@
//int [] counts = ps.executeBatch();⑶ z
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conn.commit(); 9i@*\Ada
}catch(Exception e){ z;)% i f6
e.printStackTrace(); p w8'+FX
} finally{ ^;e`ZtcI
try{ /on p<u
if(ps!=null) { '=5N?)
ps.clearParameters(); wlJ_,wA
ps.close(); 1Y_fX
ps=null; AkF3F^
} 7e4\BzCC
}catch(SQLException e){} _*_zyWW_j
DBUtils.closeConnection(conn); uxBk7E%6
} snrfHDhUw
} 1'iRx,
public long getLast(){ SJfsFi?n
return lastExecuteTime; -M:.D3,L
} S<44{
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public void run(){ xxYFWvi
long now = System.currentTimeMillis(); 1E(pJu'K
if ((now - lastExecuteTime) > executeSep) { QLn5:&
//System.out.print("lastExecuteTime:"+lastExecuteTime); 6FfDif
//System.out.print(" now:"+now+"\n"); G{<wXxq%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); E[y?\{
lastExecuteTime=now; H!N,PI?rn
executeUpdate(); s<{c?4T
} "D+QT+sD
else{ '5IJ;4k
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W c nYD)
} CwAl-o
} gS!M7xy
} DWDe5$^{
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 QP'*
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类写好了,下面是在JSP中如下调用。 ie)Qsw@
/*[a>B4-q
<% V6c?aZ,O
CountBean cb=new CountBean(); ({)_[dJ'
cb.setCountId(Integer.parseInt(request.getParameter("cid")));
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CountCache.add(cb); j_Fr3BWS
out.print(CountCache.list.size()+"<br>"); ~0`Pe{^*
CountControl c=new CountControl(); ;YB8X&H$
c.run(); rq=R},p
out.print(CountCache.list.size()+"<br>"); dg-pwWqN
%>