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: =(7nl#o
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CountBean.java EI 35&7(
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/* ML\>TDt
* CountData.java kO3\v)B;
* Pb8@owG8
* Created on 2007年1月1日, 下午4:44 "#o..?K
* `wt so
* To change this template, choose Tools | Options and locate the template under 77)WNL/
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* the Source Creation and Management node. Right-click the template and choose RM `qC
* Open. You can then make changes to the template in the Source Editor. $+7uB-KsU
*/ '-RacNY
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package com.tot.count; < z2wt
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/** @lE'D":?
* /
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* @author |0=UZK7%O
*/ +K'Hr:(
public class CountBean { ZzupK^5Z
private String countType; ySmbX
int countId; .nrllVG%`
/** Creates a new instance of CountData */ v}Ju2 }IK
public CountBean() {} rjK`t_(=
public void setCountType(String countTypes){ u7[}pf$}
this.countType=countTypes; 4_=2|2Wz[
} _#:/ ~Jp
public void setCountId(int countIds){ h.PBe
this.countId=countIds; Q&I`uS=F
} `nl n@ ;
public String getCountType(){ TMj;NSc3
return countType; I!S Eb
} !>`Fg>uy
public int getCountId(){ JaRsm'SIk~
return countId; n^T,R
} kUgfFa#_
} V3t#kv
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CountCache.java ~bhS$*t64
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/* be,Rj,-
* CountCache.java 3J+2#ML
*
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* Created on 2007年1月1日, 下午5:01 ]oB~8d
* ]h,rgO;
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose c lB K
* Open. You can then make changes to the template in the Source Editor. ccHf+=
*/ zOs}v{8"
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package com.tot.count; 9aJIq{ `E
import java.util.*; VIT|#
/** LWF,w7v[L
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* @author :D) (3U5
*/ xmvE*q"9]
public class CountCache { {?H5Pw>{%h
public static LinkedList list=new LinkedList(); tR|dnC4U
/** Creates a new instance of CountCache */ EsMX#1>/m
public CountCache() {}
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public static void add(CountBean cb){ Oo|PZ_P
if(cb!=null){ Ur(R[*2bx
list.add(cb); r0XEB,}
} 2jFuF71
} u
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} }xk(aM_
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CountControl.java oBkhb
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/* At iUTA
* CountThread.java !@=S,Vc.
* Cq\XLh `
* Created on 2007年1月1日, 下午4:57 nF,F#V8l
* &<PIm
* To change this template, choose Tools | Options and locate the template under P]43FPb
* the Source Creation and Management node. Right-click the template and choose V\;Xa0
* Open. You can then make changes to the template in the Source Editor. _B0(1(M<2
*/ \wK&wRn)
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package com.tot.count; 5qb93E"C
import tot.db.DBUtils; {]T?) !Vm
import java.sql.*; @Vre)OrN#
/** ]4l2jY
* UTD_rQ
* @author <q'l7S
*/ C`[<6>&y
public class CountControl{ f+h\RE=BGt
private static long lastExecuteTime=0;//上次更新时间 ,CfslhO{j
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 -]Z7^
/** Creates a new instance of CountThread */ r/j:A#6M]o
public CountControl() {} Dr3_MWJ+
public synchronized void executeUpdate(){ QqA=QTZ}
Connection conn=null; rAH!%~
PreparedStatement ps=null; bhqSqU}6~
try{ yQK{ +w
conn = DBUtils.getConnection(); tVAi0`DV
conn.setAutoCommit(false); y{%0[x*N<m
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ^65I,Z"
for(int i=0;i<CountCache.list.size();i++){ O3} JOv_
CountBean cb=(CountBean)CountCache.list.getFirst(); MCKN.f%lP
CountCache.list.removeFirst(); g#J`7n
ps.setInt(1, cb.getCountId()); PI9,*rOy
ps.executeUpdate();⑴ {&=+lr_h?
//ps.addBatch();⑵ YB 38K(
} TN(Vzs%
//int [] counts = ps.executeBatch();⑶ xyp{_ MZ
conn.commit(); 8xPt1Sotq[
}catch(Exception e){ hNN>Pd~;
e.printStackTrace(); *F\wWg'!B
} finally{ n
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try{ 6"Uu;Q
if(ps!=null) { 0q}i5%m7
ps.clearParameters(); Z0,jg)sA4
ps.close(); S,m(
ps=null; 5\+*ml
} D*M `qPX~
}catch(SQLException e){} EoAr}fI
DBUtils.closeConnection(conn); J:Cr.K`
} 4t,
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} aLa<zEssz
public long getLast(){ n{tc{LII/
return lastExecuteTime; 0#*6:{/^
} OQ-)
4Uk}
public void run(){ !HY^QK
long now = System.currentTimeMillis(); YuK+N
if ((now - lastExecuteTime) > executeSep) { [G<ga80
//System.out.print("lastExecuteTime:"+lastExecuteTime); yw^Pok5.
//System.out.print(" now:"+now+"\n"); n1sYD6u<&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); pbH!u+DF
lastExecuteTime=now; jIol`WX
executeUpdate(); Cj-s
} Y^fw37b
else{ \ruQx)5M
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 1m*)MZ)
} EA"hie7
} W$4$%r8
} Coi[cfg0
//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 mY"7/dw<v
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类写好了,下面是在JSP中如下调用。 #l=yD]tPU
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<% 6{h\CU}"
CountBean cb=new CountBean(); &
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); #])"1fk
CountCache.add(cb); bb6x} jR
out.print(CountCache.list.size()+"<br>"); (GJtTp~2C4
CountControl c=new CountControl(); _Mw3>GNl
c.run(); D2$9$xeR
out.print(CountCache.list.size()+"<br>"); UB$}`39@
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