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: l0Y?v 4
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CountBean.java mpAHL(
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/* 0vn[a,W<A
* CountData.java gM#jA8gz
* \-c#jo.$8
* Created on 2007年1月1日, 下午4:44 :@/"abv
* e=7W7^"_
* To change this template, choose Tools | Options and locate the template under &+G;R
* the Source Creation and Management node. Right-click the template and choose R]Ek}1~?
* Open. You can then make changes to the template in the Source Editor. SRItE\"Xe
*/ ei|cD[
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package com.tot.count; @; ;G88=
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/** doM?8C#`
* 1A^1@^{m'
* @author iX%n0i
*/ IC/Q
public class CountBean { LWD#a~
private String countType; nv)))I\
int countId; w.uK?A>W,
/** Creates a new instance of CountData */ hg8Be6G<
public CountBean() {} &\^rQi/tf
public void setCountType(String countTypes){ U-g9C.
this.countType=countTypes; yUe+":7k.
} =Dk7RKoHF
public void setCountId(int countIds){ @\jQoaLT$_
this.countId=countIds; _=EZ `!%
} Xk,>l6vc
public String getCountType(){ ZdH1nX(Yh3
return countType; ,Kw5Ro`I:
} Sy
public int getCountId(){ 1"YpO"Rh
return countId; Y\(;!o0a
} ezn`
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} $P nLG]X
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CountCache.java QPs:R hV7
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/* CT p!di|
* CountCache.java 7$7n71o
* H\#:,s {1
* Created on 2007年1月1日, 下午5:01
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* 3D_"yZ
* To change this template, choose Tools | Options and locate the template under ){ gAj
* the Source Creation and Management node. Right-click the template and choose :gf;}
* Open. You can then make changes to the template in the Source Editor. k. GA8=]>
*/ XYAmJ
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package com.tot.count; uPLErO9Es[
import java.util.*; m$:&P|!'p
/** X#ZgS!Mn
* 5)M2r!\
* @author Fw"$A0
*/ eFFc 9'o
public class CountCache { 3sbK7,4
public static LinkedList list=new LinkedList(); 6I>^Pf'ND
/** Creates a new instance of CountCache */ /g76Hw>H
public CountCache() {} !` 26\@1
public static void add(CountBean cb){ y@;%Uv&
if(cb!=null){ MhxDV d
list.add(cb); cAEok P
} au$"B/
} AVFjBybu9
} J@]k%h
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CountControl.java B4Lx{uno
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/* mQr0sI,o]
* CountThread.java 8\#
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* #SnvV
* Created on 2007年1月1日, 下午4:57 Uf$i3
* X+l'bp]Ry
* To change this template, choose Tools | Options and locate the template under :E'P7A
* the Source Creation and Management node. Right-click the template and choose O+"ac /r
* Open. You can then make changes to the template in the Source Editor. Vz"u>BP3~
*/ XYfv(y
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package com.tot.count;
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import tot.db.DBUtils; ST;t,
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import java.sql.*; &&7r+.Y
/** o~1 Kp!U
* f*fE};
* @author 1*UNsEr
*/ LchnBtjn
public class CountControl{ ?KP}#>Ba@
private static long lastExecuteTime=0;//上次更新时间
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 'jjb[{g^}}
/** Creates a new instance of CountThread */ $$1qF"GF
public CountControl() {} v\%G|8+]
public synchronized void executeUpdate(){ d,9`<1{9
Connection conn=null; i9m*g*"2
PreparedStatement ps=null; '~Q2!F
try{ YI@Fhr
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conn = DBUtils.getConnection(); =SBBvnPLI
conn.setAutoCommit(false); yPgmg@G@/
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ir[jCea,
for(int i=0;i<CountCache.list.size();i++){ ,Z~;U
CountBean cb=(CountBean)CountCache.list.getFirst(); hfrnxeM#~
CountCache.list.removeFirst(); C@gXT]Q
0}
ps.setInt(1, cb.getCountId()); qp~gP
ps.executeUpdate();⑴ >/^#Drwb!i
//ps.addBatch();⑵ UtJ a3ya
} `78V%\
//int [] counts = ps.executeBatch();⑶ ~?U*6P)o
conn.commit(); KnzsHli,~k
}catch(Exception e){ YQ]\uT>}&
e.printStackTrace(); !;3PG9n3|h
} finally{ a07=tD
try{ ll<NIdf\r
if(ps!=null) { M1!pQC_9
ps.clearParameters(); \Fb| {6+
ps.close(); Qe$k3!
ps=null; jH*)%n5,\
} _*6v|Ed?
}catch(SQLException e){} k\7:{y@,
DBUtils.closeConnection(conn); XDz5b.,
} ry0%a[[
} 9uYyfb:
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public long getLast(){ HeA{3s
return lastExecuteTime; OB^Tq~i
} PQ U]l"A
public void run(){ {9 PR()_
long now = System.currentTimeMillis(); !;
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if ((now - lastExecuteTime) > executeSep) { ^g>1U5c
//System.out.print("lastExecuteTime:"+lastExecuteTime); x\@*60o
//System.out.print(" now:"+now+"\n"); <J{'o`{
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); I+;-p]~
lastExecuteTime=now; L%cVykWY"
executeUpdate(); vqNsZ 8|`
} 5#2F1NX
else{ jC, FG'P
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); G|u3UhyB
} BNucc']
} xWX*tJ4
} eon!CE0
//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 b ,^*mx=
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类写好了,下面是在JSP中如下调用。 mpay^.(%
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<% #exss=as/
CountBean cb=new CountBean(); 7Z,/g|s}z
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 1np^(['ih
CountCache.add(cb); U4,2 br>
out.print(CountCache.list.size()+"<br>"); TMVryb
CountControl c=new CountControl(); =
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c.run(); KEr\nKT1
out.print(CountCache.list.size()+"<br>"); Ufid%T'
%>