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: 4HJZ^bq9|
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CountBean.java r
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/* ~QEXB*X-g'
* CountData.java
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* P9tQS"Rs
* Created on 2007年1月1日, 下午4:44 /qz "I-a
* 'Kso@St`o
* To change this template, choose Tools | Options and locate the template under E23 Yk?"
* the Source Creation and Management node. Right-click the template and choose 4W//Oc@e
* Open. You can then make changes to the template in the Source Editor. \w0b"p
*/ wMPw/a;
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package com.tot.count; (Q+:N;
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/** 7)(`
* V^$rH<
* @author v(Zi;?c
*/ {i%xs#0h
public class CountBean { %3l;bR>
private String countType; ^Mvsq)
int countId; 1f pS"_}
/** Creates a new instance of CountData */ D8D!1 6_
public CountBean() {} !qw=I(
public void setCountType(String countTypes){ V.gY1
this.countType=countTypes;
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} >*t>U8
public void setCountId(int countIds){ <K=B(-~
this.countId=countIds; -C'X4C+
} c%LB|(@j{
public String getCountType(){ )`+@j.75
return countType; @aV~.!!
} .dKRIFo
public int getCountId(){ yL3<X w|
return countId; 7U[L\1zS
} <Ec)m69P
} Va
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CountCache.java YT(1
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/* S_ -QvG2
* CountCache.java };|PFWs
* 5 *pN<S
* Created on 2007年1月1日, 下午5:01 ks#Z~6+3
* /jn3'q_,
* To change this template, choose Tools | Options and locate the template under 4@mXtA
* the Source Creation and Management node. Right-click the template and choose }
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* Open. You can then make changes to the template in the Source Editor. M+R)P+
*/ j.'"CU
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package com.tot.count; `w=H'"Zv
import java.util.*; dK;\`>8
/** jme5'FR
* ~!d)J
* @author ,S0~:c:)
*/ FqUt uN
public class CountCache { q}F%o0
public static LinkedList list=new LinkedList(); #HuA(``[d
/** Creates a new instance of CountCache */ O"^a.`27
public CountCache() {} &P{p\ v2Y
public static void add(CountBean cb){ )< a8a@
if(cb!=null){ G*~*2>~
list.add(cb); pn%|;
} TX
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} qD%&\ZT
} -b>O4_N
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CountControl.java %FWfiFV|<
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/* A{Htpm ~
* CountThread.java )>M@hIV5>
* '-]BSU
* Created on 2007年1月1日, 下午4:57 [`-O-?=
* 8!%"/*P$
* To change this template, choose Tools | Options and locate the template under gL}Y5U+s
* the Source Creation and Management node. Right-click the template and choose Q.2nUT`
* Open. You can then make changes to the template in the Source Editor. &|\}\+0Z
*/ Vv)E41
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package com.tot.count; S@G{|. )2
import tot.db.DBUtils; U8$dG)PhA
import java.sql.*; 9PGR#!!F$
/** Cbg#Yz~/
* e, 0I~:
* @author IS
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*/ p>tdJjnt
public class CountControl{ f<sPh>n
private static long lastExecuteTime=0;//上次更新时间 d<'Yt|zt
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 @gjdyz
/** Creates a new instance of CountThread */ s1\BjSzk
public CountControl() {} MHyl=5
public synchronized void executeUpdate(){ 2-c0/?_4
Connection conn=null; d~Ry>
PreparedStatement ps=null; ^t
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try{ Bpo68%dx89
conn = DBUtils.getConnection(); Cl.T'A$
conn.setAutoCommit(false); |j}F$*SE[
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); k\<Ln
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for(int i=0;i<CountCache.list.size();i++){ N b[o6AX
CountBean cb=(CountBean)CountCache.list.getFirst(); 0\ w[_H
CountCache.list.removeFirst(); 10 H!
ps.setInt(1, cb.getCountId()); k Q(y^t W
ps.executeUpdate();⑴ _%TeTNY#
//ps.addBatch();⑵ ^r
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} !gew;Jz
//int [] counts = ps.executeBatch();⑶ N&h!14]{Z
conn.commit(); /cen#pb
}catch(Exception e){ 1`_)%Y[ZJ
e.printStackTrace(); [_hhC
} finally{ <a[8;YQC
try{ v]U;5Uo
if(ps!=null) { 7<o;3gR7Kj
ps.clearParameters(); vGHYB1=~
ps.close(); A y[L{!)2{
ps=null; JsEEAM:w
} T`ZJ=gv
}catch(SQLException e){} 'R'a/ZR`B7
DBUtils.closeConnection(conn); 9:w,@Phe
} -86:PL(I"
} "I FGW4FnL
public long getLast(){ $cU/Im`
return lastExecuteTime; .%Q Ea_\
} ,4W((OQ^
public void run(){ y]4`d
long now = System.currentTimeMillis(); Hll}8d6[
if ((now - lastExecuteTime) > executeSep) { }/0dfes
//System.out.print("lastExecuteTime:"+lastExecuteTime); yZ0ZP
//System.out.print(" now:"+now+"\n"); +M&S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Y mjS!H
lastExecuteTime=now; r+pjv_R
executeUpdate(); ~Fb?h%w
} swL|Ff`$
else{ 2B dr#qr
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xF|*N<9(</
} .LR>&N _U
} N4jLbnA
} m9cT}x&j
//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 r['C.S6
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类写好了,下面是在JSP中如下调用。 i4rF~'h@
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<% NWK_(=n
CountBean cb=new CountBean(); ,x.)L=Cx8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); A_|FsQ6$P
CountCache.add(cb); ta.,4R&K
out.print(CountCache.list.size()+"<br>"); F]#fl%
CountControl c=new CountControl(); bI(98V,t
c.run(); H5 hUY'O
out.print(CountCache.list.size()+"<br>"); Z@/5~p
%>