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: 9p!d Q x
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CountBean.java m mw)C"
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/* \v B9fA:*
* CountData.java \["1N-q b
* fte!Ll'
* Created on 2007年1月1日, 下午4:44 \L&qfMjW"Z
* ZfF`kD\
* To change this template, choose Tools | Options and locate the template under rl_1),J\qG
* the Source Creation and Management node. Right-click the template and choose +X4ttv
* Open. You can then make changes to the template in the Source Editor. =t <:zLe
*/ .oB'ttF1
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package com.tot.count; C: TuC5Sr
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/** .XZ 71E
* 9e|{z9z[l
* @author 7zi^{]
*/ s7X~OF(#
public class CountBean { yS(=eB_
private String countType; M<hs_8_*
int countId; bDcWb2lqs
/** Creates a new instance of CountData */ JRcuw'8+q
public CountBean() {} Fb$5&~d
public void setCountType(String countTypes){ ?.|wfBI
this.countType=countTypes; :$u{
} F\YcSDM
public void setCountId(int countIds){ cPa 0n4
this.countId=countIds; yBD.Cs@
} ?`BED6$`G9
public String getCountType(){ Yn?2,^?N
return countType; *+zy\AhkP
} @/Wty@PU
public int getCountId(){ -6*OF.Ag`
return countId; lu9Ir>c
} $rV:&A
} {&Gk.ODI7
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CountCache.java *U5>j#,
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/* &'oacV=
* CountCache.java 5Rt0h$_J
* 1f bFNxo8M
* Created on 2007年1月1日, 下午5:01 ~]D\&D9=?
* #RZJ1uL
* To change this template, choose Tools | Options and locate the template under aL$c).hq0
* the Source Creation and Management node. Right-click the template and choose UC<[z#]\;
* Open. You can then make changes to the template in the Source Editor. [M zc^I&
*/ vX!dMJa0
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package com.tot.count; yQQDGFTb!=
import java.util.*; n=Z[w5
/** GurE7J^=
* a#~Z5>{
* @author y("0Xve
*/ n?KS]ar>
public class CountCache { _tR.RAaa"
public static LinkedList list=new LinkedList(); 4jZi62
/** Creates a new instance of CountCache */ jd*%.FDi{
public CountCache() {} PxCl]~v
public static void add(CountBean cb){ M,v@G$pW
if(cb!=null){ VNh,pQ(
list.add(cb); [F9KC^%S
} j#.-MfB
} Duo#WtC
} SS<+fWXE
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CountControl.java QYCNO#*
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/* BIB>U W
* CountThread.java o^"d2=
* 7l|>
* Created on 2007年1月1日, 下午4:57 ~QQ23k&
* 1rzq$, O
* To change this template, choose Tools | Options and locate the template under \t~u
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* the Source Creation and Management node. Right-click the template and choose S0o,)`ZB
* Open. You can then make changes to the template in the Source Editor. \gk3w,B?E
*/ )v$Cv|"
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package com.tot.count; /x"pj3
import tot.db.DBUtils; >+c`GpZH
import java.sql.*; "x) pp
/** ,Elga}7u
* DF&jZ[##
* @author dXcMysRc%&
*/ N<i Vs
public class CountControl{ VRN9 yn2
private static long lastExecuteTime=0;//上次更新时间 /dP8F
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 |LGNoP}SA
/** Creates a new instance of CountThread */ zR/p}Wu|!
public CountControl() {} MZ+IorZl
public synchronized void executeUpdate(){ U8I~co:h
Connection conn=null; aPP<W|Cmo2
PreparedStatement ps=null; 2g07wJ6x
try{ laRKt"A
conn = DBUtils.getConnection(); (NWN&
conn.setAutoCommit(false); e4_aKuA
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W3-Rs&se
for(int i=0;i<CountCache.list.size();i++){ &oEq&
CountBean cb=(CountBean)CountCache.list.getFirst(); i:Ct6[
CountCache.list.removeFirst(); ?lw[
ps.setInt(1, cb.getCountId()); @p'v.;~#
ps.executeUpdate();⑴ D+U/ ]sW
//ps.addBatch();⑵ X52jqXjg
} !JQ~r@j
//int [] counts = ps.executeBatch();⑶ m$UT4,Ol
conn.commit(); Q Fqv,B\<
}catch(Exception e){ })u}PQ
e.printStackTrace(); es(LE/`e
} finally{ n^(yW
try{ _q 9lr8hx
if(ps!=null) { QNI|h;D
ps.clearParameters(); hO@v\@;r
ps.close(); wyhf:!-I
ps=null; S2GBX1
} >wm$,%zk
}catch(SQLException e){} u~T$F/]k>
DBUtils.closeConnection(conn); H;!hp0y
} f*&JfP
} GB0b|9(6D"
public long getLast(){ >^ 1S26
return lastExecuteTime; $5AtI$TV_!
} ifCGNvDR
public void run(){ _"Ke=v_5
long now = System.currentTimeMillis(); (pK4i5lT
if ((now - lastExecuteTime) > executeSep) { ?m7" G)
//System.out.print("lastExecuteTime:"+lastExecuteTime); FG36,6N%2j
//System.out.print(" now:"+now+"\n"); xla^A}{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 9}Ave:X^
lastExecuteTime=now; {3uSg)
executeUpdate(); Wjk;"_"gd
} !P^$g
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else{ 1? hd
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); qJzK8eW
} v})Ti190
} a7d-
} 12DdUPOi
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 v@s`l#
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类写好了,下面是在JSP中如下调用。 2EcYO$R!
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<% %}5"5\Zz
CountBean cb=new CountBean(); R[-:-8
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); _qo1 GM&
CountCache.add(cb); l"!;Vkg.5
out.print(CountCache.list.size()+"<br>"); 3n)iTSU3
CountControl c=new CountControl(); ,#;ahwU~s
c.run(); Elk$9 <<
out.print(CountCache.list.size()+"<br>"); b!P;xLcb
%>