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: >
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CountBean.java A-io-P7qyj
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/* r Lh
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* CountData.java =<05PB
* _:L*{=N
* Created on 2007年1月1日, 下午4:44 .T|NB8 rS
* xD=D *W
* To change this template, choose Tools | Options and locate the template under rYJ))@
* the Source Creation and Management node. Right-click the template and choose R}>Do=hAO
* Open. You can then make changes to the template in the Source Editor. ,gvX ~k
*/ !D3}5A1,
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package com.tot.count; }D^Gt)
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/** CA4-&O"
* o^?{j*)g
* @author WI6E3,ejB1
*/ *ls6#j@
public class CountBean { bwJi[xF
private String countType;
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int countId; eFQi
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/** Creates a new instance of CountData */ 4Le5Ms/
public CountBean() {} o,yvi
public void setCountType(String countTypes){ yLx.*I^6
this.countType=countTypes; [q&J"dt
} c)8wO=!
public void setCountId(int countIds){ Ic
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this.countId=countIds; qt(:bEr^6b
} 8ilbX)O
public String getCountType(){ IdxTo Mr
return countType; 4AYc8Z#'
} Xoy 1Gi?
public int getCountId(){ zq.&Mw?
return countId; ]3xa{h~4
} =]a@)6y
} %7#Zb '
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CountCache.java
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/* 3kCbD=yF
* CountCache.java Y14R"*t~
* Wu( 8G
* Created on 2007年1月1日, 下午5:01 `tG_O
* s
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* To change this template, choose Tools | Options and locate the template under Rda1X~-g
* the Source Creation and Management node. Right-click the template and choose e<4z)
* Open. You can then make changes to the template in the Source Editor. :dN35Y] a
*/ /8}+#h)[
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package com.tot.count; U.U.\
import java.util.*; es[5B* 5
/** K eI:/2
* CLEG'bZa,
* @author e:LZ s0
*/ $ud>Z;X=P
public class CountCache { 1gm/{w6O
public static LinkedList list=new LinkedList(); O&w3@9KJ?
/** Creates a new instance of CountCache */ l;*lPRoW,
public CountCache() {} 1bg@[YN!;
public static void add(CountBean cb){ @$d\5Q(G
if(cb!=null){ i\;&CzC:
list.add(cb); `E=rh3 L0o
} cqY.^f.
} xm|4\H&Bg
} yH%+cmp7
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CountControl.java {(}w4.!
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/* SU
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* CountThread.java `u~
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* Created on 2007年1月1日, 下午4:57 ~f10ZB_k>'
* "42$AaS
* To change this template, choose Tools | Options and locate the template under f WjS)
* the Source Creation and Management node. Right-click the template and choose >zg8xA1zL
* Open. You can then make changes to the template in the Source Editor. &]6K]sWJK{
*/ Kn#xY3W6
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package com.tot.count; a^c,=X3
import tot.db.DBUtils; N~5WA3xd
import java.sql.*; :F>L;mp
/** s.;KVy,=Bu
* 90iW-"l+[
* @author l ~4e2xoT
*/ 5u)^FIBj
public class CountControl{ A
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private static long lastExecuteTime=0;//上次更新时间 h0GdFWN
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 /P!X4~sTM
/** Creates a new instance of CountThread */ 4 uy @ {
public CountControl() {} 9Ir~X|}\iL
public synchronized void executeUpdate(){ y-<PsP-I
Connection conn=null; t+!gzZ
PreparedStatement ps=null; <]Pix)
try{ ?PE1aB+{:
conn = DBUtils.getConnection(); IEoR7:
conn.setAutoCommit(false); >9tkx/J
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); >\7RIy3
for(int i=0;i<CountCache.list.size();i++){ &lh_-@Xz
CountBean cb=(CountBean)CountCache.list.getFirst(); |:=b9kv
CountCache.list.removeFirst(); !|<f%UO
ps.setInt(1, cb.getCountId()); *K jVPs
ps.executeUpdate();⑴ pmW6~%}*
//ps.addBatch();⑵ t6bWSz0
} I0l.KiBm
//int [] counts = ps.executeBatch();⑶ xeYySM=
conn.commit(); I"Q9W|J_&
}catch(Exception e){ ;/";d]j
e.printStackTrace(); /cL9?k;o
} finally{ FJjF*2 .
try{ I6hhU;)C
if(ps!=null) { ;;y@z[ >
ps.clearParameters(); z<[.MH`ln
ps.close(); R!/,E
ps=null; 4-M6C 5#.
} Eo {1y
}catch(SQLException e){}
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DBUtils.closeConnection(conn); +<!)k?
} "`jZ(+
}
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public long getLast(){ mU?&\w=v$
return lastExecuteTime; SJ@8[n.x
} yToT7 X7F7
public void run(){ Xw*%3'
long now = System.currentTimeMillis(); ;ad9{":J#B
if ((now - lastExecuteTime) > executeSep) { 4('0f:9z+
//System.out.print("lastExecuteTime:"+lastExecuteTime); GwMUIevO_
//System.out.print(" now:"+now+"\n"); neB.Wu~WH
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); +2V%'{:
lastExecuteTime=now; \}u7T[R=`
executeUpdate(); Owh*KY:
} Q_dXRBv=n
else{ 9!O+Ryy?\
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} hHfe6P
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} iC\rhHKQ
} ,WO%L~db
//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 t7*G91Hoq&
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类写好了,下面是在JSP中如下调用。 =0s`4Y"+
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<% <nOuyGIZ
CountBean cb=new CountBean(); r?"}@MRW
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); $LxG>db
CountCache.add(cb); GFQG(7G9
out.print(CountCache.list.size()+"<br>"); ~51kiQW
CountControl c=new CountControl(); EbBv}9g
c.run(); xS
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out.print(CountCache.list.size()+"<br>"); ,<Grd5em.
%>