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: :o8`2Z *g
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CountBean.java D-/6RVq0m
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/* "BSY1?k{
* CountData.java IVh5SS
* /GGyM]k3
* Created on 2007年1月1日, 下午4:44 UH>~Y
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* 7_ix&oVI
* To change this template, choose Tools | Options and locate the template under ch8VJ^%Ra1
* the Source Creation and Management node. Right-click the template and choose 4uiq'-
* Open. You can then make changes to the template in the Source Editor. i6V$m hL
*/ w317]-n
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package com.tot.count; iXm&\.%
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/** U6/7EOW,
* Jt5V{9:('
* @author ltuV2.$
*/ /= ;,lC
public class CountBean { [`GSc6j
private String countType; +=J$:/&U
int countId; r[V%DU$dj
/** Creates a new instance of CountData */ 5Hu[*
public CountBean() {} anW['!T9{s
public void setCountType(String countTypes){ [nxYfER7
this.countType=countTypes; :<P4=P P
} gg#9I(pX
public void setCountId(int countIds){ i[KXkjr
this.countId=countIds; Fl.?*KBz
} z|3v~,
public String getCountType(){ @]n8*n
return countType; q.=Q
} H7+z"^s*
public int getCountId(){
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return countId; :'bZ:J>f
} /}@F
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} }BM`4/
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CountCache.java \YzKEYx+
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/* HjK8y@j
* CountCache.java (5jKUQ8Q>
* 7Y@]o=DIc
* Created on 2007年1月1日, 下午5:01 FL \pgbI
* ^rfR<Q`
* To change this template, choose Tools | Options and locate the template under /)TeG]Xg
* the Source Creation and Management node. Right-click the template and choose b<y*:(:
* Open. You can then make changes to the template in the Source Editor. 4S'e>:
*/ o`n8Fk}i
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package com.tot.count; &qWg$_Yh
import java.util.*; cV>?*9z0
/** #D_Ti%.^}
* T2rwK2
* @author `>\
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*/ Vw w 211
public class CountCache { Kq")|9=d
public static LinkedList list=new LinkedList(); sP^:*B0
/** Creates a new instance of CountCache */
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public CountCache() {} OulRqbL2
public static void add(CountBean cb){ 2T*kmDp
if(cb!=null){ "*#f^/LS
list.add(cb); --y,ky#
} Pa{DB?P
} g"sb0d9
} /ZiMD;4@y
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CountControl.java Z]Xa:[
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/* je$H}D
* CountThread.java ~Zsj@d
* #8t=vb3
* Created on 2007年1月1日, 下午4:57 7a9">:~
* D>jtz2y=D
* To change this template, choose Tools | Options and locate the template under 8#$HKWUK
* the Source Creation and Management node. Right-click the template and choose BD]J/o
* Open. You can then make changes to the template in the Source Editor. KLM6#6`
*/ z#RwgSPw6
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package com.tot.count; {G=> WAXo
import tot.db.DBUtils; 5(#z)T
import java.sql.*; 8-+# !]
/** ]uhG&:
}
* Fb<'L5}i
* @author 0(c,J$I]Z!
*/ &kdW(;`
public class CountControl{ G$YF0Nc
private static long lastExecuteTime=0;//上次更新时间 NUnwf
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private static long executeSep=60000;//定义更新间隔时间,单位毫秒 qDGx(d
/** Creates a new instance of CountThread */ NblPVxS
public CountControl() {} uD{-a$6z
public synchronized void executeUpdate(){ 4?@5JpC9VA
Connection conn=null; $o+@}B0)
PreparedStatement ps=null; g&/lyQ+G
try{ "n3n-Y#'
conn = DBUtils.getConnection(); #vK99S2
conn.setAutoCommit(false); Vfd_nD^8oZ
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); I SZEP8w
for(int i=0;i<CountCache.list.size();i++){ ^Vth;!o
CountBean cb=(CountBean)CountCache.list.getFirst(); t@lTA>;U@
CountCache.list.removeFirst(); "
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ps.setInt(1, cb.getCountId()); i8Be%y%y
ps.executeUpdate();⑴ n. N0Nhd
//ps.addBatch();⑵ Kc]
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} &56\@t^
//int [] counts = ps.executeBatch();⑶ fR;[??NH
conn.commit(); :Hitx
}catch(Exception e){ B[sI7D>Y
e.printStackTrace(); evEdFY
} finally{ %m lH
try{ |(x%J[n0+
if(ps!=null) { SgQmR#5
ps.clearParameters(); U{EcV%C2
ps.close(); eYRd#w
ps=null; Zu#^a|PE*
} ;(E]mbV'=
}catch(SQLException e){} 1|
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DBUtils.closeConnection(conn); D {E,XOi
} 0RdW.rZJ
} ~]%re9jGW
public long getLast(){ rr1,Ijh{D
return lastExecuteTime; F'<XB~&o
} :[?7,/w
public void run(){ D@w&[IF
long now = System.currentTimeMillis(); /FTP8XHwL)
if ((now - lastExecuteTime) > executeSep) { mtFC H
//System.out.print("lastExecuteTime:"+lastExecuteTime); meB9:w[m
//System.out.print(" now:"+now+"\n"); %j2 :W\g:
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }cW8B"_"
lastExecuteTime=now; hHEn
executeUpdate(); Q Wm
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} Rz>@G>b:
else{ p*$=EomY
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); (8S+-k?
} 4nd)*0{f
} )MN 6\v
} :`yW^b
//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 &_QD1 TT
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类写好了,下面是在JSP中如下调用。 29@m:=-}7
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<% Ki:98a$
CountBean cb=new CountBean(); AA|G&&1y
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 9Z2aFW9
CountCache.add(cb); =;8q`
out.print(CountCache.list.size()+"<br>"); H-&
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CountControl c=new CountControl(); xjDaA U,
c.run(); q/7T-"q/G
out.print(CountCache.list.size()+"<br>"); :d<F7`k
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