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: 8+5-7)
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CountBean.java u_.`I8qa
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/* PqMU&H_
* CountData.java [ Fid
* \hSOJ,{)U
* Created on 2007年1月1日, 下午4:44 g0-hN%=6
* rf.w}B;V;
* To change this template, choose Tools | Options and locate the template under MqXN,n+`k
* the Source Creation and Management node. Right-click the template and choose Jq1 Zb
* Open. You can then make changes to the template in the Source Editor. C!N&uNp@s
*/ ]<D9Q>
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package com.tot.count; IZ /M d@C
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/** mgeNH~%m@*
* p;av63i
* @author $0rSb0[
*/ MrIo.
public class CountBean { { Z<4
private String countType; ]wLHe2bEu
int countId; _iBNy
/** Creates a new instance of CountData */ CA[-\>J7y
public CountBean() {} 9H5S@w[je
public void setCountType(String countTypes){ jdxwS
this.countType=countTypes; ZgCG'SU
} =>".
public void setCountId(int countIds){ .{as"h-.O
this.countId=countIds; ^S*~<0NQ'
} 9I*zgM!F
public String getCountType(){ VZNMom,Wr
return countType; e2|2$|
} \`?l6'!
public int getCountId(){ F3/aq+<P[
return countId; .L'>1H]B
} +rS}f
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} l0Wp%T
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CountCache.java F"xD^<i
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/* L~fxVdUz
* CountCache.java "\bbe @
* Y9fktg.
* Created on 2007年1月1日, 下午5:01 k4te[6)
* NDLk+n
* To change this template, choose Tools | Options and locate the template under &6nOCU)
* the Source Creation and Management node. Right-click the template and choose Rk8>Ak(/
* Open. You can then make changes to the template in the Source Editor. , Z*Fo: q
*/ SBo>\<@
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package com.tot.count; )`?Es8uW
import java.util.*; *Q=ER
/** <oG+=h
* ehQ"<.sQ
* @author a]^hcKo4
*/ Z+h^ ie"g
public class CountCache { .ky((
public static LinkedList list=new LinkedList(); $@kGbf~k
/** Creates a new instance of CountCache */ iL f:an*vH
public CountCache() {} (6i)m
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public static void add(CountBean cb){ ~`M>&E@Y_/
if(cb!=null){ "X~ayn'@w,
list.add(cb); ZzET8?8
} %O-RhB4q
} =~Oi:+L
} 8%OS ,Z
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CountControl.java S'~Zlv3`
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/* $!P(Q
* CountThread.java tpw0j
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* = Ly7H7Q2
* Created on 2007年1月1日, 下午4:57 t]1j4S"pm
* Am=D kkP%
* To change this template, choose Tools | Options and locate the template under ,|SO'dG
* the Source Creation and Management node. Right-click the template and choose Bs2.$~
* Open. You can then make changes to the template in the Source Editor. <1#v}epD#
*/ Ezw(J[).C
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package com.tot.count; Oq~>P!=
import tot.db.DBUtils; ZzfGs
import java.sql.*; Ql8E9~h
/** BEM_y:#
* IxC/X5Mp^q
* @author `c@KlL*!Q
*/ Yjxa=CD
public class CountControl{ OoOKr
private static long lastExecuteTime=0;//上次更新时间 A-gNfXP,D
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 g0t$1cUR
/** Creates a new instance of CountThread */ pVe@HJy6G
public CountControl() {} pC,MiV$c"
public synchronized void executeUpdate(){ Rfh#JO@%[
Connection conn=null; SpbOvY=>
PreparedStatement ps=null; xzF@v>2S+
try{ fhqc[@Y[
conn = DBUtils.getConnection(); hU=n>g>nx
conn.setAutoCommit(false); v|acKux=t
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); lV!ecJw$
for(int i=0;i<CountCache.list.size();i++){ XE);oL2xP
CountBean cb=(CountBean)CountCache.list.getFirst(); "'p;Udt/Qm
CountCache.list.removeFirst(); \wR bhN
ps.setInt(1, cb.getCountId());
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ps.executeUpdate();⑴ 0]
e=
//ps.addBatch();⑵ e|Iylv[3
} +P,hT
//int [] counts = ps.executeBatch();⑶ tj 6 #lM9
conn.commit(); TTcMIMyLT
}catch(Exception e){ b*=eMcd
e.printStackTrace(); m}w~ d /
} finally{ H
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try{ w^tNYN,i
if(ps!=null) { _ +Ww1f
ps.clearParameters(); 4eapR|#T
ps.close(); f h05*]r
ps=null; WP&P#ju&
} X8l[B{|
}catch(SQLException e){} QCkPua9
DBUtils.closeConnection(conn); e#0C
} _YzItge*
} {>[,i`)
public long getLast(){ j|3p.Cy
return lastExecuteTime; oLVy?M%{P
} B0I(/ 7
public void run(){ n%PHHu
long now = System.currentTimeMillis(); vk\a>};
if ((now - lastExecuteTime) > executeSep) { 5Z{i't0CQ
//System.out.print("lastExecuteTime:"+lastExecuteTime); +')\,m "z
//System.out.print(" now:"+now+"\n"); 1(0LX^%
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Cv{>|g#
lastExecuteTime=now; >mRA|0$
executeUpdate(); 4Z>KrFO
} M\zM-B
else{ 8Z{&b,Y4L
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); "w]
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} \{
} &Ji!*~sE
} e"HA.t[A
//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 h-u63b1"?
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类写好了,下面是在JSP中如下调用。 ^(7<L<H
$ )q?z.U
<% 7+wy`xi
CountBean cb=new CountBean(); \zioIfHm
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); >Qg`Us#y
CountCache.add(cb); jyRSe^x
out.print(CountCache.list.size()+"<br>"); -[A4B)
CountControl c=new CountControl(); WVDkCo@
c.run(); E0QrByr_
out.print(CountCache.list.size()+"<br>"); )P
%>