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: G/<zd)
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CountBean.java d"9tP&
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/* **Ioy+
* CountData.java hr
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* Created on 2007年1月1日, 下午4:44 05q760I+
* bGH#s {'5
* To change this template, choose Tools | Options and locate the template under j)mU`b_
* the Source Creation and Management node. Right-click the template and choose }q.D)'g_
* Open. You can then make changes to the template in the Source Editor. 5]N0p,f
*/ |(3y09
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package com.tot.count; lx%c&~.DiB
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/** fd&Fn=!
* 1@}F8&EZ
* @author <|}Z6Ti
*/ Z^&G9I#
public class CountBean { ~R
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private String countType; WzN c=@[W
int countId; #T_!-;(Z
/** Creates a new instance of CountData */ '"
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public CountBean() {} A-CU%G9
public void setCountType(String countTypes){ 9j>2C
this.countType=countTypes; vn^O m-\
} G<$:[ +w
public void setCountId(int countIds){ #cfiN b}GX
this.countId=countIds; ;\mX=S|a
} 8(%F{&<;
public String getCountType(){ G;G*!nlWf
return countType; JY#vq'dl|
} X3:z=X&Zd
public int getCountId(){ ZL6HD n!
return countId; wf\"&xwh?
} cmG27\c RO
} ;{sZDjev>
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CountCache.java NZvgkci_(u
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/* @*YF!LdU{M
* CountCache.java ! Ld5Y$
* =6[.||9
* Created on 2007年1月1日, 下午5:01 u?Ffqt9'
* f1 x&Fk
* To change this template, choose Tools | Options and locate the template under F}_b7|^
* the Source Creation and Management node. Right-click the template and choose ;'n%\*+fHH
* Open. You can then make changes to the template in the Source Editor. =GX5T(P8k
*/ 6!m#;8 4
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package com.tot.count; &j F'2D^_
import java.util.*; *-nO,K>y`
/** Te+(7
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* el9P@r0
* @author mAW.p=;
*/ u5oM;#{@-
public class CountCache { |2j,
public static LinkedList list=new LinkedList(); PEf yHf7`
/** Creates a new instance of CountCache */ }HoCfiE=X
public CountCache() {} e'3V4iU]
public static void add(CountBean cb){ X,k^p[Rcu
if(cb!=null){ $gUlM+sK
list.add(cb); N#T'}>t y
} ^jMrM.GY
} + `|A/w
} ,UY1.tR(
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CountControl.java ks#3
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/* -#|;qFD]
* CountThread.java l)%PvLbL
* Tx;a2:6\[
* Created on 2007年1月1日, 下午4:57 =NF0E8O
* ..)J6L5l
* To change this template, choose Tools | Options and locate the template under $l]:2!R
* the Source Creation and Management node. Right-click the template and choose qIi
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* Open. You can then make changes to the template in the Source Editor. _i05'_
*/ r:g\
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package com.tot.count; EqW~K@
import tot.db.DBUtils; 1+FVM\<&
import java.sql.*; q?}C`5%D
/** iW` tr
* Lnh=y2
* @author PK[mf\G\
*/ ojd0um6I{
public class CountControl{ ybBmg'198
private static long lastExecuteTime=0;//上次更新时间 {18hzhs
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 tMxde+$y
/** Creates a new instance of CountThread */ k>($[;k|b
public CountControl() {} (P|[<Sd
public synchronized void executeUpdate(){ Tv=lr6t8
Connection conn=null; (7Z+ De?
PreparedStatement ps=null; `8!9Fp
try{ h=#w< @
conn = DBUtils.getConnection(); `B)@
conn.setAutoCommit(false); Z`S#> o
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w2DC5ei'
for(int i=0;i<CountCache.list.size();i++){ ix!xLm9\
CountBean cb=(CountBean)CountCache.list.getFirst(); m/=nz.
CountCache.list.removeFirst(); A=N$5ZJ
ps.setInt(1, cb.getCountId()); 28!C#.(h
ps.executeUpdate();⑴ AP&//b,^M
//ps.addBatch();⑵ 53i]Q;k [
} h:aa^a~yi
//int [] counts = ps.executeBatch();⑶ [neuwdN
conn.commit(); E5ce=$o
}catch(Exception e){ QLd*f[n
e.printStackTrace(); m!<HZvq?vf
} finally{ UGcmzwE
try{ :?Ns>#6t
if(ps!=null) { 7ch9Pf
ps.clearParameters(); mLhM_=
ps.close(); /v
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ps=null; Q~N,QMr)k&
} 981-[ga`Y
}catch(SQLException e){} -<#)
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DBUtils.closeConnection(conn); Nfa&r
} 5XKTb
} S{=5nR9 j
public long getLast(){ /WN YS
return lastExecuteTime; G2`z?);1b
} ~5KcbGD~
public void run(){ b80#75Bj>
long now = System.currentTimeMillis(); Y(PCc}/\
if ((now - lastExecuteTime) > executeSep) { k\f
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//System.out.print("lastExecuteTime:"+lastExecuteTime); J,Sa7jv[
//System.out.print(" now:"+now+"\n"); )WqolB
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); /qLO/Mim
lastExecuteTime=now; "hk#pQ
executeUpdate(); e*:K79y
} | v!N1+v0
else{ 1VJ${\H]
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p D<w@2K
} $.`o
} ?NMk|+
} 8 .%0JJ .3
//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 QEyL/#Q
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类写好了,下面是在JSP中如下调用。 +z;*r8d<X
_T\ ~%
<% PT/Nz+
CountBean cb=new CountBean(); I6.rN\%b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); UoT`/.
CountCache.add(cb); }A3/(
out.print(CountCache.list.size()+"<br>"); =D1
CountControl c=new CountControl(); _p )NZ7yC
c.run(); v=llg ^
out.print(CountCache.list.size()+"<br>"); @v)Z>xv
%>