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: >xrO W`p]
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CountBean.java ERD( qL.J
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/* r+%:rFeX
* CountData.java
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* /$
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* Created on 2007年1月1日, 下午4:44 zURxXo/\V
* c1 aCN
* To change this template, choose Tools | Options and locate the template under "Kky|(EQ$$
* the Source Creation and Management node. Right-click the template and choose Nfe
* Open. You can then make changes to the template in the Source Editor. WqQAt{W/<
*/ &j=FxF9o
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package com.tot.count; Mj&`Y
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/** 3ht>eaHi
* n^vL9n_N
* @author S:!gj2q9|
*/ c#o(y6
public class CountBean { %c+`8 wj
private String countType; 12l-NWXf
int countId; NqyKR&;
/** Creates a new instance of CountData */ [R
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public CountBean() {} ,36AR|IO)
public void setCountType(String countTypes){ |,!]]YO.V
this.countType=countTypes; tF lLKziU
} u /PaXQ
public void setCountId(int countIds){ cHqT1EY
this.countId=countIds; >f)/z$
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} ^na8d's:
public String getCountType(){ pc9m,?n
return countType; m#
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} _cPGS=Ew
public int getCountId(){ BG ]w2=
return countId; 2"0q9 Jg
} \l)Jb*t
} EFpV
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CountCache.java g-G;8x'n
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/* ":=\ci]e%
* CountCache.java RNa59b
* hF m_`J&"
* Created on 2007年1月1日, 下午5:01 GD*rTtDWn
* poLzgd
* To change this template, choose Tools | Options and locate the template under G@$Y6To[
* the Source Creation and Management node. Right-click the template and choose UqVcN$^b
* Open. You can then make changes to the template in the Source Editor. GM]" $
*/ %Xe#'qNq)
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package com.tot.count; z"7I5N
import java.util.*; BhAWIH8@C
/** M$Sq3m`{!
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* @author 8&[Lr o9
*/ I^}q;L![\
public class CountCache { U&F1}P$fb
public static LinkedList list=new LinkedList(); 9)c{L<o}T
/** Creates a new instance of CountCache */ d7,ZpHt
public CountCache() {} [D;wB|+,
public static void add(CountBean cb){ ~7CQw^"R@
if(cb!=null){ \!-IY
list.add(cb); _LVwjZX[
} ,=TY:U;?
} V]E#N
} g+(Cs
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CountControl.java 6_UCRo5h%
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/* 7(8i~}
* CountThread.java fEv`iXZG
* 31VDlcnE
* Created on 2007年1月1日, 下午4:57 tW^oa
* J \06j%d,
* To change this template, choose Tools | Options and locate the template under
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* the Source Creation and Management node. Right-click the template and choose gKPqWh
* Open. You can then make changes to the template in the Source Editor. uUhqj.::<Y
*/ 6[.#B!;9
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package com.tot.count; $ ,:3I*}be
import tot.db.DBUtils; w^Mj[v#
import java.sql.*; ON,sN
/** z (1zth
* dM-qd`
* @author 9+i rf^D`O
*/ OBnf5*eJ
public class CountControl{ f`;y
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private static long lastExecuteTime=0;//上次更新时间 i}tBB~]
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]VKM3[
/** Creates a new instance of CountThread */ tfKf*Um
public CountControl() {} LqYP0%7
public synchronized void executeUpdate(){ yr;~M{{4
Connection conn=null; Q>ZxJ!B<k
PreparedStatement ps=null; kT-dQ32
try{ |2Krxi3*
conn = DBUtils.getConnection(); O c,E\~
conn.setAutoCommit(false); 0 _n
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); (7X|W<xT
for(int i=0;i<CountCache.list.size();i++){ RJp Rsr
CountBean cb=(CountBean)CountCache.list.getFirst(); zh.^>
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CountCache.list.removeFirst(); y
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ps.setInt(1, cb.getCountId()); "V=IG{.
ps.executeUpdate();⑴ |]M|IX8
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//ps.addBatch();⑵ kVmRv.zZ
} Yg<L pjq5X
//int [] counts = ps.executeBatch();⑶ Ri
conn.commit(); #oYPe:8|m
}catch(Exception e){ Hto RN^9
e.printStackTrace(); bHKTCPf
} finally{ m}-*B1
try{ {+3
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if(ps!=null) { 7I $~E
ps.clearParameters(); '!hA!eo>J
ps.close(); yv;KKQ
ps=null; JI3x^[(Z
} cj64.C
}catch(SQLException e){} = :/4)
DBUtils.closeConnection(conn); x]Pp|rHj
} >eC>sTPQ{
} SzTa[tJ+
public long getLast(){ 2FVO@D
return lastExecuteTime; "y9]>9:$-
} X7~^D[X
public void run(){ hEh` cBO
long now = System.currentTimeMillis(); %&5PZmnW
if ((now - lastExecuteTime) > executeSep) { /g]NC?
//System.out.print("lastExecuteTime:"+lastExecuteTime); IDY2X+C#U
//System.out.print(" now:"+now+"\n"); !,cLc}a
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); QomihQnc
lastExecuteTime=now; : MEB] }
executeUpdate(); Q M) ob
} 5(\H:g\z
else{ cr`NHl/XF
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); p9y@5z
} Bjp4:;Bb
} `DFo:w!k
} 5%jy7)8C
//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 n~Yr`5+Z
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类写好了,下面是在JSP中如下调用。 $~,J8?)(z
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<% U^;|as
CountBean cb=new CountBean(); )z_5I (?&
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <\'aUfF v
CountCache.add(cb); QPyHos`
out.print(CountCache.list.size()+"<br>"); V<i_YLYmJe
CountControl c=new CountControl(); W]oILL"d
c.run(); 8+,I(+
out.print(CountCache.list.size()+"<br>"); 47=YP0r?>T
%>