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: $'#hCs
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CountBean.java ha+)ZF
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/* ' jAX&7G`
* CountData.java , TL8`
* 8i:E$7e tH
* Created on 2007年1月1日, 下午4:44 6v(?Lr`D
* BZHba8c(
* To change this template, choose Tools | Options and locate the template under ,gAa9
* the Source Creation and Management node. Right-click the template and choose BN??3F8C
* Open. You can then make changes to the template in the Source Editor. 8$)xxV_zp
*/ <r 2$k"*:
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package com.tot.count; Sep/N"7~t
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/** >1luLp/,$
* ?r
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* @author yR?S]
*/ ZSWKVTi
public class CountBean { =+>cTV
private String countType; 7dxTyn=
int countId; )wT@`p"4
/** Creates a new instance of CountData */ ;W"=s79
public CountBean() {} nh"8on]M~
public void setCountType(String countTypes){ 4WspPHj
this.countType=countTypes; z{;~$."
} Z'hHXSXM
public void setCountId(int countIds){ [%?ViKW
this.countId=countIds; 2Kg-ZDK8
} ?rauhTVnJ
public String getCountType(){ 3UXaA;
return countType; MKiP3kt8
} NgI n\)
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public int getCountId(){ U+[ p>iP
return countId; .|?UqZ(,
} 3.0t 5F<B
} k`aHG8S\
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CountCache.java #!yW)RG
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/* _|^cudRv
* CountCache.java -K%hug
* G!<-9HA5
* Created on 2007年1月1日, 下午5:01 ~7;AV(\%e
* `J
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* To change this template, choose Tools | Options and locate the template under yq6Gyoi<
* the Source Creation and Management node. Right-click the template and choose A
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* Open. You can then make changes to the template in the Source Editor. G*N}X3H:o
*/ Y%zYO
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package com.tot.count; .X.,.vHx
import java.util.*; j3t,Cx
/** ;ElwF&"!X
* zm~sq_=^
* @author |~]@hs~
*/ lnQfpa8j
public class CountCache { T8t_+|(
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public static LinkedList list=new LinkedList(); R!z32 <5k
/** Creates a new instance of CountCache */ dTTC6?yPXf
public CountCache() {} KAI/*G\z
public static void add(CountBean cb){ &x.n>O
if(cb!=null){ e8,!x9%J
list.add(cb); nhImO@Q:
} o=)["V
} ^| r6>b
} @3v[L<S{
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CountControl.java !;%+1j?d
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/* E``\Jre@
* CountThread.java ir<K"wi(2
* qBDhCE
* Created on 2007年1月1日, 下午4:57 \Y$@$)
* |T+YC[T#v
* To change this template, choose Tools | Options and locate the template under /cC4K\M
* the Source Creation and Management node. Right-click the template and choose d`sIgll&n
* Open. You can then make changes to the template in the Source Editor. c2~oPUj
*/ S2PPwCU
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package com.tot.count; LUKt!I0l
import tot.db.DBUtils; :=oIvSnh
import java.sql.*; p%#=OtkC
/** rp_Aw
* VlFhfOR6t
* @author *z
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*/ Mh"vH0\Lj
public class CountControl{ b{(= C
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private static long lastExecuteTime=0;//上次更新时间 5J2tR6u-(
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 e\95X{_'
/** Creates a new instance of CountThread */ q c DJ
public CountControl() {} $Ma*q EB
public synchronized void executeUpdate(){ %T,cR>lw
Connection conn=null; cL+bMM$4r~
PreparedStatement ps=null; ?656P=b)
try{ "}^}3"/.
conn = DBUtils.getConnection(); jn._4TQ*}
conn.setAutoCommit(false); ?F^O7\rw
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); w\%AR1,rs
for(int i=0;i<CountCache.list.size();i++){ /7&WFCc)(
CountBean cb=(CountBean)CountCache.list.getFirst(); >o4Ih^VB
CountCache.list.removeFirst(); \:Z8"~G
ps.setInt(1, cb.getCountId()); gxCl=\
ps.executeUpdate();⑴ Q7pjF`wu
//ps.addBatch();⑵ g93Hl&
} ;dquld+q
//int [] counts = ps.executeBatch();⑶ TFI$>Oz|
conn.commit(); rOTxD/
}catch(Exception e){ O)D+u@RhH
e.printStackTrace(); [?S-on.
} finally{ gV;9lpZ2
try{ k*|WI$
if(ps!=null) { eD)@:K
ps.clearParameters(); Rd,5&X$
ps.close(); r#\Lq;+-B
ps=null; #sb@)Q
} 8^5@J)R8
}catch(SQLException e){} AI9#\$aGV
DBUtils.closeConnection(conn); ~!#2s'
} 8?G534*r@2
} T3In0LQ
public long getLast(){ pe>[Ts`2F
return lastExecuteTime; q4]Qvf>
} n1)~/
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public void run(){ ~vw$Rnotz
long now = System.currentTimeMillis(); 6rh^?B
if ((now - lastExecuteTime) > executeSep) { *B%ulsm
//System.out.print("lastExecuteTime:"+lastExecuteTime); n|) JhXQ
//System.out.print(" now:"+now+"\n"); f!13Ob<8r
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); N6w!V]b
lastExecuteTime=now; yBnUz"
executeUpdate(); #8i9@w
} U^d!*9R
else{ ]Nb~-)t%B
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n");
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} x?n13C
} Tw@:sWC
} 3GM9ZPeN:
//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 a4x(lx&
*s6(1S
类写好了,下面是在JSP中如下调用。 >/9on.
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<% e8VtKVcY
CountBean cb=new CountBean(); ]udH`{]
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); LHHDD\X
CountCache.add(cb); lj"72
out.print(CountCache.list.size()+"<br>"); k*!f@ M
CountControl c=new CountControl(); C$7dmGjZ
c.run(); z~\Y*\f^Y3
out.print(CountCache.list.size()+"<br>"); p[:E$#W~;
%>