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: nkPh,X\N0
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CountBean.java R*,MfV
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/* .'6gZKXY
* CountData.java 7g^]:3f!
* XPc^Tq
* Created on 2007年1月1日, 下午4:44 [NTzcSN.
* 8\^R~K`sY
* To change this template, choose Tools | Options and locate the template under Xg6Jh``
* the Source Creation and Management node. Right-click the template and choose JtE M,tK
* Open. You can then make changes to the template in the Source Editor. Ov@gh
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*/ {p2!|A&a
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package com.tot.count; t9lPb_70
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/** <sbu;dQ`
* )$2QZ
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* @author hgG9m[?K
*/ M-VX;/&FR
public class CountBean { "nynl'Ryk
private String countType; 2k~l$p>CN!
int countId; SO/c}vnBB
/** Creates a new instance of CountData */ AYBns]!
public CountBean() {} #^0R&) T
public void setCountType(String countTypes){ VD*6g%p
this.countType=countTypes; x8 2cT21b
} h'llK6_)
public void setCountId(int countIds){ 9cbd~mM{
this.countId=countIds; h,:m~0gmj
} gjyYCjF
public String getCountType(){ P\tB~SZ*
return countType; >58YjLXb
} [>I<#_^~
public int getCountId(){ l:~/<`o
return countId; J3V=
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} uo9B9"&
} ;?Tbnn Wn
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CountCache.java n`_{9R
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/* ,_ H:J.ik
* CountCache.java mthA4sz
* n&4N[Qlv,
* Created on 2007年1月1日, 下午5:01 C}j"Qi`
* N{!i=A
* To change this template, choose Tools | Options and locate the template under 5{WE~8$
* the Source Creation and Management node. Right-click the template and choose UW={[h{.|@
* Open. You can then make changes to the template in the Source Editor. KfEx"94
*/ Y1\ }5k{>
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package com.tot.count; Pbn*_/H
import java.util.*; x;.Jw6g
/** 9.M4o[
* )
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* @author H7Rx>h_
*/ ?=msH=N<l
public class CountCache { /U*C\ xMm
public static LinkedList list=new LinkedList(); J1U/.`Oy
/** Creates a new instance of CountCache */ q[_VuA]&
public CountCache() {} oH?b}T=9jz
public static void add(CountBean cb){ p<FzJ
if(cb!=null){ HyQJXw?A:
list.add(cb); O/(`S<iip
} }"H,h)T
} R%WCH?B<}
}
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CountControl.java &m7]v,&
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/* sE<V5`Z=
* CountThread.java 79j+vH!zh
* H2 {+)
* Created on 2007年1月1日, 下午4:57 u~:y\/Y6
* 05#1w#i
* To change this template, choose Tools | Options and locate the template under PdFKs+Z`
* the Source Creation and Management node. Right-click the template and choose h2A <" w
* Open. You can then make changes to the template in the Source Editor. qA7>vi%
*/ k"%~"9
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package com.tot.count; :pY/-Cgv
import tot.db.DBUtils; fw~Bza\e
import java.sql.*; +o{R _
/** M/'sl;
* U}[d_f
* @author bH9kj/q\b
*/ UhWNl]Z
public class CountControl{ )EuvRLo{S7
private static long lastExecuteTime=0;//上次更新时间 HWrO"b*tO
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 {]!mrAjD
/** Creates a new instance of CountThread */ i#/Jr=
public CountControl() {} {lDd.Fn
public synchronized void executeUpdate(){ {4}yKjW%z
Connection conn=null; pj{`';
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PreparedStatement ps=null; XEp{VC@=
try{ ]cWUZ{puRB
conn = DBUtils.getConnection(); n)-$e4u2
conn.setAutoCommit(false); {6|G@""O
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); *%NT~C
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for(int i=0;i<CountCache.list.size();i++){ /t57!&
CountBean cb=(CountBean)CountCache.list.getFirst(); ~H_/zK6e
CountCache.list.removeFirst(); nNV'O(x}
ps.setInt(1, cb.getCountId()); =:Fc;n>c<K
ps.executeUpdate();⑴ Fnv;^}\z
//ps.addBatch();⑵ }eU*(
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} ~$cV:O7
//int [] counts = ps.executeBatch();⑶ Lx1FpHo
conn.commit(); KP^V>9q
}catch(Exception e){ `2WFk8) F
e.printStackTrace(); )[6U^j4
} finally{ xC:L)7#aw
try{ qJs<#MQ2
if(ps!=null) { L| +~"'l
ps.clearParameters(); P6`u._mX
ps.close(); iN\4gQ!
ps=null; zkrM/ @p#
} 4r#= *
}catch(SQLException e){} orpri O|qD
DBUtils.closeConnection(conn); -HbC!wv
} [A~xy'T
} iRbT/cc{
public long getLast(){ -#[a7',Z;
return lastExecuteTime; _ QI\
} z+wA
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public void run(){ !u[9a;Sa#
long now = System.currentTimeMillis(); }5[qo`M
if ((now - lastExecuteTime) > executeSep) { 'RR~7h
//System.out.print("lastExecuteTime:"+lastExecuteTime); '~<m~UXvD#
//System.out.print(" now:"+now+"\n"); #aJ(m&
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 81F/G5
lastExecuteTime=now; . B9iLI
executeUpdate(); LVfF[
} Ecefi
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else{ &K.d'$q
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); m+R[#GE8#
} 3?9IJ5p
} YeL#jtC
} J.b9F:&}
//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 t;Sb/ 3
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类写好了,下面是在JSP中如下调用。 e7Z32P0ls
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<% Su7?;Oh/yI
CountBean cb=new CountBean(); $\BE&4g
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); S(I{NL}=$
CountCache.add(cb); L|:`^M+^w
out.print(CountCache.list.size()+"<br>"); .-c4wm}
CountControl c=new CountControl(); =E4LRKn
c.run(); Q5`*3h6p=
out.print(CountCache.list.size()+"<br>"); kQSy+q
%>