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: ]S L&x:/-
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CountBean.java 8j}m\^si
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/* cPcV[6)5K9
* CountData.java ?/(K7>`
* b-?o?}*
* Created on 2007年1月1日, 下午4:44 Z?.*.<"Sj
* v+#j>
* To change this template, choose Tools | Options and locate the template under dYd~9
* the Source Creation and Management node. Right-click the template and choose WDdi}i>2
* Open. You can then make changes to the template in the Source Editor. E/ZJ\@gzD
*/ ]eW|}V7A:
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package com.tot.count; ugB{2oq i
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/** Wu( 8G
* `tG_O
* @author kZ9<j+.
*/ Rda1X~-g
public class CountBean { e<4z)
private String countType; ?+5{HFx
int countId; :dN35Y] a
/** Creates a new instance of CountData */ !&O/7ywe
public CountBean() {} A#X.c=
public void setCountType(String countTypes){ *BsDHq-F~
this.countType=countTypes; `M ygDG+u
} &8_;:
public void setCountId(int countIds){ zD^f%p ["#
this.countId=countIds; nq f<NH3i
} {*;]I?9Al
public String getCountType(){ C..2y4bA}
return countType; OLNn3
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} "t:.mA<v
public int getCountId(){ fVUBCu
return countId; k6'#
} Nf 'dT;s.N
} =t$mbI
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CountCache.java t;dQ~e20
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/* s~Wu0%])Q
* CountCache.java `qDz=,)WP
* -`dxx)x
* Created on 2007年1月1日, 下午5:01 sN1*Zp'(
* Mc7 <[a
* To change this template, choose Tools | Options and locate the template under cm@ oun
* the Source Creation and Management node. Right-click the template and choose ZqbM%(=z(`
* Open. You can then make changes to the template in the Source Editor. ~5 pC$SC6>
*/ S~rVRC"<xo
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package com.tot.count; |369@un6
import java.util.*; EB2^]?
/** #4_O;]{'
* EkStb#
* @author b6!Q!:GO&
*/ wAYzR$i
public class CountCache { _"!{7e`Z
public static LinkedList list=new LinkedList(); c+b:K
/** Creates a new instance of CountCache */ I"Q9W|J_&
public CountCache() {} $qlqWy-s
public static void add(CountBean cb){ Gp ^ owr
if(cb!=null){ Z|:_c
list.add(cb); <S8I"8{Mb
} ;%rs{XO9
} oj^5G
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} =>:% n
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CountControl.java K*Nb_|~
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/* +%e%UF@
* CountThread.java \9>g;qPg}
* U|
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* Created on 2007年1月1日, 下午4:57 Pzk[^z$C
* Q_dXRBv=n
* To change this template, choose Tools | Options and locate the template under )-Mn"1ia
* the Source Creation and Management node. Right-click the template and choose xyS2_Q
* Open. You can then make changes to the template in the Source Editor. #"o6OEy$A#
*/ =p,4=wo{
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package com.tot.count; c<+g|@A#
import tot.db.DBUtils; $LxG>db
import java.sql.*; oz\{9Lwc
/** Sr ztTfY
* JO&;bT<
* @author Jm]]>K8.3V
*/ 9LqMQv"xW
public class CountControl{ bG5^h
private static long lastExecuteTime=0;//上次更新时间 S<y>Y
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 8"?Vcw&
/** Creates a new instance of CountThread */ CzzUi]*Ac{
public CountControl() {} /^z/]!JG:V
public synchronized void executeUpdate(){ R<y Nv
Connection conn=null; VeNNsg>&
PreparedStatement ps=null; `r~`N`o5A
try{ =9DhO7I'
conn = DBUtils.getConnection(); Z9J =vzsHE
conn.setAutoCommit(false);
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ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); KD,^*FkkL
for(int i=0;i<CountCache.list.size();i++){ DqurHQ z)m
CountBean cb=(CountBean)CountCache.list.getFirst(); DGa#d_I
CountCache.list.removeFirst(); Jo7fxWO_g
ps.setInt(1, cb.getCountId()); a2cx
ps.executeUpdate();⑴ Zzw}sZ?8
//ps.addBatch();⑵ eEW roF
} 36kc4=
//int [] counts = ps.executeBatch();⑶ " ;-{~
conn.commit(); xE G+%Uk{
}catch(Exception e){ u|_LR5S!j
e.printStackTrace(); RlI
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} finally{ k8InbX[
try{ _SMT.lG
if(ps!=null) { QmWC2$b
ps.clearParameters(); ]Wy^VcqX
ps.close(); q;~R:}?@
ps=null; 4)z3X\u|Z2
} -,K*~z.l
}catch(SQLException e){} oJlN.Q#u&
DBUtils.closeConnection(conn); |x1$b7
} #[no~&E
} 3M}AxE u
public long getLast(){ 8pXfT%]
return lastExecuteTime; 1zdYBb6;j
} ~ GNyE*t/Y
public void run(){ {@Blj3 ;w}
long now = System.currentTimeMillis(); 3cmbK
if ((now - lastExecuteTime) > executeSep) { !Bag}|#
//System.out.print("lastExecuteTime:"+lastExecuteTime); Vil@?Y"
//System.out.print(" now:"+now+"\n"); QH& %mr.S
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }=Hf?';m
lastExecuteTime=now; V^j3y`K
executeUpdate(); MNkKy(Za
} 6o$Z0mG
else{ TAXd,z N
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); -sP9E|/:'3
} @[n2dmj
} CKJAZ 2
} RI?NB6U
//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 ;_x2Ymw
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类写好了,下面是在JSP中如下调用。 fwRGT|":B
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<% QxKAXq@)i
CountBean cb=new CountBean(); X
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cb.setCountId(Integer.parseInt(request.getParameter("cid"))); t9ER;.e
CountCache.add(cb); "K8nxnq
out.print(CountCache.list.size()+"<br>"); ^GN5vT+:'
CountControl c=new CountControl();
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c.run(); TV<Aj"xw
out.print(CountCache.list.size()+"<br>"); RvWFF^, .
%>