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: s=d+GMa
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CountBean.java (=1q!c`
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/* ZXsYn
* CountData.java QsF4Dl
* dhHEE|vrz
* Created on 2007年1月1日, 下午4:44 s`hav
* G#H9g PY
* To change this template, choose Tools | Options and locate the template under bD35JG^&i
* the Source Creation and Management node. Right-click the template and choose RF_[?O)Q
* Open. You can then make changes to the template in the Source Editor. X JY5@I.
*/ ^qxdmMp)l
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package com.tot.count; BeK2;[5C
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/** <EMkD1e
* =m}TU)4.
* @author I>A^I
*/ ]gu1#
public class CountBean { Q|Pbt(44
private String countType; n]+.
int countId; sVu k
/** Creates a new instance of CountData */ .H8mRvd?
public CountBean() {} 1SW4Y
public void setCountType(String countTypes){ |q;Al
z{
this.countType=countTypes; rA,CQypo
} Xv0F:1
public void setCountId(int countIds){ K@HQrv<
this.countId=countIds; \a\= gn
} U98_M)-%&
public String getCountType(){ ->\N_|_
return countType; Ap%O~wA'
} q
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public int getCountId(){ Z>F@nTzb>
return countId; k6@b|
} J58#$NC
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} @\)fzubu
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CountCache.java Z_FNIM0f
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/* rvic%bsk
* CountCache.java R2w`Y5#`
* &5u BNpH
* Created on 2007年1月1日, 下午5:01 Y0@yD#,0~
* mDfwn7f
* To change this template, choose Tools | Options and locate the template under #vQ?
* the Source Creation and Management node. Right-click the template and choose QY@u}&m%o
* Open. You can then make changes to the template in the Source Editor. LM:)j:gS6
*/ d$K=c1
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package com.tot.count; e*:}$u8a
import java.util.*; JA`H@qE
/** f&ytK
* FI{AZb_'
* @author h*s`^W3
*/ @EHIp{0.
public class CountCache { SK+@HnKd
public static LinkedList list=new LinkedList(); IIxJqGN:
/** Creates a new instance of CountCache */ e_/x&a(i8
public CountCache() {} s~J=<)T*6
public static void add(CountBean cb){ <F7V=Er
if(cb!=null){ R:/ha(+
list.add(cb); WmNYO,>
} t?{B_Bf
} -`7$Qu2
} !\;:36B#6
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CountControl.java mV?&%>*(f
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/* :y#T9R9
* CountThread.java R"+wih
* o.Oq__ >$H
* Created on 2007年1月1日, 下午4:57 Nb;H`<JP
* )TU<:V
* To change this template, choose Tools | Options and locate the template under h*Je35
* the Source Creation and Management node. Right-click the template and choose tPU-1by$
* Open. You can then make changes to the template in the Source Editor. Uoji@
*/ s<vs:jna
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package com.tot.count; 7Fz
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import tot.db.DBUtils; \}JrFc%O
import java.sql.*; #Qh>z%Mn^3
/** b9Y_!Qe
* - $JO8'TP
* @author >w.'KR0L
*/ C>X|VP|C
public class CountControl{ ]^K;goQv
private static long lastExecuteTime=0;//上次更新时间 VFj(M
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /0lC KU!=
/** Creates a new instance of CountThread */ S~)w\(r
public CountControl() {} z/ 7$NxJH
public synchronized void executeUpdate(){ 3;_
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Connection conn=null; -(#-I$z
PreparedStatement ps=null; LA4<#KP
try{ ;`(R7X
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conn = DBUtils.getConnection(); MBw-*K'?zB
conn.setAutoCommit(false); 8IGt4UF&?
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); _1|$P|$P.
for(int i=0;i<CountCache.list.size();i++){ /L v1$~
CountBean cb=(CountBean)CountCache.list.getFirst(); 7I}P*%(f
CountCache.list.removeFirst(); #BY`h~&T
ps.setInt(1, cb.getCountId()); #@qN8J}R
ps.executeUpdate();⑴ 6/tI8H3E
//ps.addBatch();⑵ SfB8!V|;
} m"d/b~q
//int [] counts = ps.executeBatch();⑶ uzBz}<M=
conn.commit(); ?j{C*|yHO
}catch(Exception e){ OBOwz4<
e.printStackTrace(); =o^|b ih
} finally{ WeMAe
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try{ sx
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if(ps!=null) { A:# k
ps.clearParameters(); DBs DkkB{
ps.close(); M#,Q
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ps=null; j6g@tx^)'
} 8=;k"
}catch(SQLException e){} 'bu )M1OLi
DBUtils.closeConnection(conn); >t <pFh
} &@v<nO-
} t'1Y@e
public long getLast(){ YF[f Z
return lastExecuteTime; 9V
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} N|:'XwL
public void run(){ 0CAa^Q^w
long now = System.currentTimeMillis(); $t/rOo9cV
if ((now - lastExecuteTime) > executeSep) { 7J*N_8?2
//System.out.print("lastExecuteTime:"+lastExecuteTime); 1n=_y o
//System.out.print(" now:"+now+"\n"); L":bI&V?:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H !)=y
lastExecuteTime=now; x_MJJ(q8g
executeUpdate();
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} *>q/WLR
else{ sZhMa>
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 'Ot,H_pE
} a|_p,_
} 9YN?
} e8P-k3a"5:
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 .Zmp ,
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类写好了,下面是在JSP中如下调用。 QM<y`cZ8
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<% },@^0UH4c
CountBean cb=new CountBean(); S*
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 7 sFz?`-
CountCache.add(cb); y$W|~ H
out.print(CountCache.list.size()+"<br>");
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CountControl c=new CountControl(); )3A{GZj#6
c.run(); BiwieF4x
out.print(CountCache.list.size()+"<br>"); !mJo'K
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