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: %1Pn;bUU!
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CountBean.java ?9)-?tZ^Q
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/* .7"]/9oB
* CountData.java 6AW{qU6
* Eoo[)V#x{
* Created on 2007年1月1日, 下午4:44 v|r=}`k=
* 3TDjWW;#~
* To change this template, choose Tools | Options and locate the template under @TTB$
* the Source Creation and Management node. Right-click the template and choose }%;o#!<N(@
* Open. You can then make changes to the template in the Source Editor. V&75n.L
*/ (6*CORE
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package com.tot.count; r- :u*
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/** O
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* bZB7t`C5
* @author 0 kM4\En
*/ 9O.okU
public class CountBean { `qnNEJL,
private String countType; S1B^FLe7X
int countId;
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/** Creates a new instance of CountData */ scsN2#D7U/
public CountBean() {} I!L`W
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public void setCountType(String countTypes){ l; ._
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this.countType=countTypes; T|{1,wP
} gq^j-!Q)Q<
public void setCountId(int countIds){ #nv =x&g
this.countId=countIds; Wt%+q{
} ^D=1%@l?#
public String getCountType(){ 88GS Bg:YH
return countType; ^"?fZSC
} =y$|2(6
public int getCountId(){ *QIlh""6
return countId; 5ZX P$.
} #Oeb3U
} k[`9RGT
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CountCache.java k\qF> =
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/* m@z.H ;
* CountCache.java YA:7^-Bv
* %ZajM
* Created on 2007年1月1日, 下午5:01 w4m)lQM
* {7%W/C#A
* To change this template, choose Tools | Options and locate the template under DLWG0$#!
* the Source Creation and Management node. Right-click the template and choose srh>"
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* Open. You can then make changes to the template in the Source Editor. nI_43rG:Uf
*/ Ob+Rnfx37
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package com.tot.count; m!qbQMXn
import java.util.*; yFYFFv\?
/** z;dFS
* 0Q]ZS
* @author kTjx.
*/ |A'y|/)#Z
public class CountCache { ~ryB*eZH
public static LinkedList list=new LinkedList(); xE2sb*
/** Creates a new instance of CountCache */ &RzkM4"
public CountCache() {} =nQgS.D
public static void add(CountBean cb){ 'nrXRDb
if(cb!=null){ * 7<{Xbsj^
list.add(cb); 0I`)<o-
} /oWn0
} .}wVM`81z
} q,8TOn
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CountControl.java /{[Y l[{"<
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/* cL]vJ`?Ih
* CountThread.java .;1tu+S
* 8,0WHivg
* Created on 2007年1月1日, 下午4:57 |[RoR
* YPV@/n[N
* To change this template, choose Tools | Options and locate the template under ZCT\4Llv#
* the Source Creation and Management node. Right-click the template and choose JBYmy_Su
* Open. You can then make changes to the template in the Source Editor. %z0;77[1 I
*/ )\qA[rTG
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package com.tot.count; X3bPBv
import tot.db.DBUtils; U/W<Sa\`
import java.sql.*; Z8 X=Md8=
/** ;V=Y#|o
* z^ai *
* @author b6mSPH@
*/ GQ@`qYLZ+
public class CountControl{ j.?c~Fh
private static long lastExecuteTime=0;//上次更新时间 b-d{)-G{(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 = 02$Dwr
/** Creates a new instance of CountThread */ B=>VP-:
public CountControl() {} V>$A\AWw
public synchronized void executeUpdate(){ ?F^$4:
Connection conn=null; 0bR)]"K
PreparedStatement ps=null; <Va7XX%>
try{ fI_I0dc.p
conn = DBUtils.getConnection(); z frEM
conn.setAutoCommit(false); %M=Ob k
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); L[|($vQ"
for(int i=0;i<CountCache.list.size();i++){ /#lqv)s'
CountBean cb=(CountBean)CountCache.list.getFirst(); !iys\ AV
CountCache.list.removeFirst(); r@O5{V
ps.setInt(1, cb.getCountId()); uuD|%-Ng
ps.executeUpdate();⑴ DFk0"+Ky
//ps.addBatch();⑵ 7CK3t/3D
} B$Z%_j&
//int [] counts = ps.executeBatch();⑶ isG8S(}IW&
conn.commit(); Q1b<=,
}catch(Exception e){ 4R(H@p%+r2
e.printStackTrace(); t-gLh(-.
} finally{ /S9(rI<'
try{ `/"rs@
if(ps!=null) { 17
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ps.clearParameters(); ccdP}|9e
ps.close(); :Zs i5>MT
ps=null; 3.t
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} v_ U$jjO1
}catch(SQLException e){} >-%}'iz+
DBUtils.closeConnection(conn); @L 9C_a
} pL&
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} ,cesQ
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public long getLast(){ <-]qU}-
return lastExecuteTime; JNJ96wnX1
} N<$dbqoT|
public void run(){ b%-S'@ew
long now = System.currentTimeMillis(); y[C++Q
if ((now - lastExecuteTime) > executeSep) { A"V($:>U
//System.out.print("lastExecuteTime:"+lastExecuteTime); /O^aFIxk
//System.out.print(" now:"+now+"\n"); '[Ue0r<jn
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); c SV`?[a
lastExecuteTime=now; 7 K5D,"D;1
executeUpdate(); 9GV1@'<Y]
} Qf>$'C(7!a
else{ 'o!{YLJ fM
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); _x2i=SFo*$
} Mur)'
} o4zX
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} 1Z h4)6x
//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 ^%qe&Pe2
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类写好了,下面是在JSP中如下调用。 Fuz'!
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<% !jySID?q
CountBean cb=new CountBean(); ZNKopA(=|%
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); r*r3QsO
CountCache.add(cb);
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out.print(CountCache.list.size()+"<br>"); _, ki/7{
CountControl c=new CountControl(); xsO
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c.run(); O-=~Bn
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out.print(CountCache.list.size()+"<br>"); UGb<&)
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