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: 4cott^K.
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CountBean.java |:./hdcad
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/* D,c!#(v cK
* CountData.java JT4wb]kdV
* JDkCUN 5
* Created on 2007年1月1日, 下午4:44 SXQ@;=]xV
* "Owct(9
* To change this template, choose Tools | Options and locate the template under rVUUH!
* the Source Creation and Management node. Right-click the template and choose 0yn[L3x7
* Open. You can then make changes to the template in the Source Editor. n%F-cw
*/ Z+NF(d
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package com.tot.count; 8QT<M]N%
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/** q<n[.u1@
* F;#zN
* @author h aCKv
*/ 92ZWU2"
public class CountBean { Ffnk1/Zy
private String countType; CK2 B
int countId; y>$1UwQ
/** Creates a new instance of CountData */ XcOA)'Py
public CountBean() {} +fM&su=wl
public void setCountType(String countTypes){ S"zk!2@C
this.countType=countTypes; x5oOF7#5
} a>U6Ag<
public void setCountId(int countIds){ ,"B?_d6
this.countId=countIds; (4~X}:
} Mal <iNN
public String getCountType(){ ba8 6 N
return countType; ,I ZqLA
} .hKhrcQp
public int getCountId(){ a.?v*U@z@#
return countId; 'fIHUw|
} $`pd|K`
} =ai2z2z
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CountCache.java W@^J6sH
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/* flP>@i:e6
* CountCache.java zDB"r
* h}h^L+4
* Created on 2007年1月1日, 下午5:01 t)} \9^Uo
* |=O1Hn
* To change this template, choose Tools | Options and locate the template under R"Kz!NTB
* the Source Creation and Management node. Right-click the template and choose L x.jrF|&
* Open. You can then make changes to the template in the Source Editor. cJ.
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*/ GzdRG^vN
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package com.tot.count; .$Y?
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import java.util.*; oE1M/*myS
/** {SJsA)9:#
* )B ;M
* @author i
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*/ m<{"}4'
public class CountCache { KnJx{8@z
public static LinkedList list=new LinkedList(); C`NmZwL
/** Creates a new instance of CountCache */ =p q:m
public CountCache() {} DVh)w}v
public static void add(CountBean cb){ MWs~#ReZ
if(cb!=null){ hk_g2g
list.add(cb); oSY7IIf%L
} -(9O6)Rs$
} X'x3esw w
} D,Lp|V
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CountControl.java 3rNc1\a;
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/* L+.H z&*@
* CountThread.java ul@3
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* I^G^J M!
* Created on 2007年1月1日, 下午4:57 h=6xZuA\
* F+ukAT
* To change this template, choose Tools | Options and locate the template under Q_]~0PoH
* the Source Creation and Management node. Right-click the template and choose 6aY>lkp
* Open. You can then make changes to the template in the Source Editor. q>-R3HB
*/ rLzW`
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package com.tot.count; cKjRF6w
import tot.db.DBUtils; pDn&V(
import java.sql.*; #byJqy&e
/** ?v4E<iXs
* K(VW%hV1
* @author d2~l4IL)~
*/ _R^y\1Qu
public class CountControl{ \GL*0NJ
private static long lastExecuteTime=0;//上次更新时间 b+{r!D}~
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 \}#@9=
/** Creates a new instance of CountThread */ zTY;8r+
public CountControl() {} mj2Pk,,SA
public synchronized void executeUpdate(){ Nqcp1J"
Connection conn=null; z)}!e,7
PreparedStatement ps=null; ETfF5i}
try{ <6jFKA<
conn = DBUtils.getConnection(); CZ(`|;BC*
conn.setAutoCommit(false); k!3 cq)
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); GoIQ>n
for(int i=0;i<CountCache.list.size();i++){ O~PChUU*Y
CountBean cb=(CountBean)CountCache.list.getFirst(); . I==-|
CountCache.list.removeFirst(); Vb!O8xV4;+
ps.setInt(1, cb.getCountId()); c-B/~&
ps.executeUpdate();⑴ R0wf#%97
//ps.addBatch();⑵ {DwIjy31T
} W`M6J}oG
//int [] counts = ps.executeBatch();⑶ ,mKObMu
conn.commit(); "3}<8c
}catch(Exception e){ TH4\HY9qa?
e.printStackTrace(); (0L=AxH
} finally{ vtyx`F
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try{ "^Rv#
if(ps!=null) { YQd:M%$
ps.clearParameters(); wL3,g2- L
ps.close(); CU$#0f>
ps=null; bd==+
} Td h TQ
}catch(SQLException e){} {C")#m-0
DBUtils.closeConnection(conn); rN5tI.iC
} q3h'l,
} BBnq_w"a
public long getLast(){ 7-*=|gl+
return lastExecuteTime; V%NeZ1{ e
} K_ke2{4Jm
public void run(){ UyiJU~r1
long now = System.currentTimeMillis(); aG{$Ic
if ((now - lastExecuteTime) > executeSep) { u9Y3?j,oC
//System.out.print("lastExecuteTime:"+lastExecuteTime); ]
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//System.out.print(" now:"+now+"\n"); {(tHk_q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Ri)uq\E/#
lastExecuteTime=now; 9Ah[rK*}
executeUpdate(); 8-Me.2K
} jfp z`zE
else{ qP1FJ89H
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); wK!~tYxP
} h|)vv4-d|
} lV6dm=k
} PsnGXcj
//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 ke%pZ7{u
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类写好了,下面是在JSP中如下调用。 _#C()Ro*P
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<% KzO,*M
CountBean cb=new CountBean(); j0mM>X HB
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 27A!\pn
CountCache.add(cb); NM#-Af*pg
out.print(CountCache.list.size()+"<br>"); nxo+?:**
CountControl c=new CountControl(); ?LP9iY${
c.run(); gfg n68k
out.print(CountCache.list.size()+"<br>"); cWLqU
%>