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: iKu4s
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CountBean.java \027>~u
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/* Z1_F)5pn
* CountData.java /[!<rhY
* 9"zp>VR
* Created on 2007年1月1日, 下午4:44 1A[(R T]
* B!U;a=ia
* To change this template, choose Tools | Options and locate the template under 4v`G/w
* the Source Creation and Management node. Right-click the template and choose Lngf,Of.e
* Open. You can then make changes to the template in the Source Editor. ^!z(IE'
*/ / ;+Mz*
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package com.tot.count; +J#8wh
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/** A0OA7m:~4
* \BX9Wn*)a
* @author +S WtHj7e
*/ Bg}l$?S
public class CountBean { {< EPm&q
private String countType; %y7ZcH'
int countId; 1Vc~Sa
/** Creates a new instance of CountData */
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public CountBean() {} q[9N4nj$<
public void setCountType(String countTypes){ &xZSM,
this.countType=countTypes; E#,\[<pc
} Ow(aRWUZD_
public void setCountId(int countIds){ ,U)&ny
this.countId=countIds; xGFbh4H=8p
} -9;?k{{[T
public String getCountType(){ Q @[gj:w
return countType; s6r(\L_Im
} sWB@'P:x
public int getCountId(){ Gpi_p
return countId; H23 O]r
} }Q@~_3,UJ
} 78r0K 5=
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CountCache.java IZ\fvYp
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/* "Q:h[) a
* CountCache.java &n#yxv4
* oz]&=>$1I
* Created on 2007年1月1日, 下午5:01 Gs,e8ri!
* TD%L`Gk
* To change this template, choose Tools | Options and locate the template under ,7k-LAA
* the Source Creation and Management node. Right-click the template and choose ~mwIr
* Open. You can then make changes to the template in the Source Editor. qj `C6_?
*/ *A4eYHn@
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package com.tot.count; cA|vH^:
import java.util.*; z@w}+fYO
/** rV4K@)~
* ||.Hv[
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* @author ~MXhp5PI
*/ GNEPb?+T
public class CountCache { 9_,f)2)~W
public static LinkedList list=new LinkedList(); T,jb%uPcE
/** Creates a new instance of CountCache */ uubIL+
public CountCache() {} Y/"t!
public static void add(CountBean cb){ 8UXRM :Z"
if(cb!=null){ /nu z_y\J
list.add(cb); gu%i|-}
} zx,9x*g
} f$n5$hJlQ
} $IjI{%
{
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CountControl.java =6O*AJ
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/* &"I csxG
* CountThread.java %[s%H)e)
* "tl$JbRTY
* Created on 2007年1月1日, 下午4:57 m{?f,Q=u@
* Crg'AB?
* To change this template, choose Tools | Options and locate the template under y+w,j]
* the Source Creation and Management node. Right-click the template and choose vp.?$(L^@/
* Open. You can then make changes to the template in the Source Editor. B>m*!n:l
*/ a'/i/@h
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package com.tot.count; &e;Qabwxva
import tot.db.DBUtils; ^3S&LC
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import java.sql.*; "y&`,s5}
/** M@<9/xPS
* f7][#EL
* @author Qubu;[0+a
*/ uOJqj{k_."
public class CountControl{ ' h<(
private static long lastExecuteTime=0;//上次更新时间 R3l{.{3p2
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 zBTW&
/** Creates a new instance of CountThread */ B(94; ,(
public CountControl() {} M<n'ZDK`W
public synchronized void executeUpdate(){ H?8'(
Connection conn=null; m,!SDCq
PreparedStatement ps=null; RR
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try{ FE&:?
conn = DBUtils.getConnection(); :S_]!'H
conn.setAutoCommit(false); VZI!rFac
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {vCtp
for(int i=0;i<CountCache.list.size();i++){ \#t)B
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CountBean cb=(CountBean)CountCache.list.getFirst(); 0
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CountCache.list.removeFirst(); 9jqsEd-SW
ps.setInt(1, cb.getCountId()); BLO ]78
ps.executeUpdate();⑴ ^N|8
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//ps.addBatch();⑵ o!KDeY
} , >S7c
//int [] counts = ps.executeBatch();⑶ W_JO~P
conn.commit(); wN4#j}C
}catch(Exception e){ \rzMgR$/rj
e.printStackTrace(); ?\, ^>4x?
} finally{ z<vh8dNl
try{ ]kTxVe
if(ps!=null) { QO(F%&v++
ps.clearParameters(); w,FPL&{
ps.close(); ">z3i`#C'
ps=null; @|c])
} jd-]q2fQ|
}catch(SQLException e){} yvoz 3_!
DBUtils.closeConnection(conn); ~r5S{&
} UWvVYdy7
} aYb97}kI
public long getLast(){ diY7<u#
return lastExecuteTime; ; s/<wx-C
} ud$-A
public void run(){ 3EICdC
long now = System.currentTimeMillis(); {XmCG%%L
if ((now - lastExecuteTime) > executeSep) { * /n8T]s
//System.out.print("lastExecuteTime:"+lastExecuteTime); ")STB8kQ
//System.out.print(" now:"+now+"\n"); % (y{Sca
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); za@/4z
lastExecuteTime=now; j/d}B_2
executeUpdate(); ~EPVu
} 2]]v|Z2M4
else{ +wmG5!%$|
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); aY>v
} BA]$Fi.Mw
} \}?X5X>
} LD}~]
//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 ZhA_d#qH
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类写好了,下面是在JSP中如下调用。 $}gMJG
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<% W-n4wIj"
CountBean cb=new CountBean(); LnI
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 3uqhYT;
CountCache.add(cb); 6`e7|ilh6
out.print(CountCache.list.size()+"<br>"); MVsFi]-
CountControl c=new CountControl(); rm,`M
c.run(); VWvSt C
out.print(CountCache.list.size()+"<br>"); GT&}Burl/n
%>