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: |`yzH$,F
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CountBean.java IfGQeynj
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/* xr\wOQ*`
* CountData.java (" +/ :
* CF k^(V"
* Created on 2007年1月1日, 下午4:44 #Zy-X_r
* hf1f
* To change this template, choose Tools | Options and locate the template under 3e.v'ccK&
* the Source Creation and Management node. Right-click the template and choose 7VwLyy
* Open. You can then make changes to the template in the Source Editor. K?o} B
*/ JV#)?/a$z
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package com.tot.count;
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/** &G>EBKn\2`
* wGC)gW
* @author ]8X Y"2b
*/ $*{$90Q
public class CountBean { )2P4EEs[
private String countType; -\`n{$OR
int countId; K"sfN~@rT[
/** Creates a new instance of CountData */ M7(vI4V
public CountBean() {} *L9s7RR
public void setCountType(String countTypes){ \
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this.countType=countTypes; wxg`[c$:
} !m#cneV
public void setCountId(int countIds){ Gd~Xvw,u
this.countId=countIds; AVR9G^ce_
} ZL`G<Mo;.
public String getCountType(){ <~}t;ji
return countType; !j)H!|R
} =Po!\[SBU
public int getCountId(){ @awaN
return countId; $+<X 1
} *a@pZI0'
} w49Wl>M
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CountCache.java =>hq0F4[;
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/* &
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* CountCache.java ;C%D+"l1g
* sa`7_KB
* Created on 2007年1月1日, 下午5:01 ?rQMOJR
* TD-d5P^Kek
* To change this template, choose Tools | Options and locate the template under q0
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* the Source Creation and Management node. Right-click the template and choose vL13~q*F
* Open. You can then make changes to the template in the Source Editor. `
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*/ DFs
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package com.tot.count; )}?'1ciHI
import java.util.*; 56*}}B$?
/** \qAMs^1-
* vZC2F
* @author sb_>D`>
*/ 0K,*FdA
public class CountCache { Xt/T0.I
public static LinkedList list=new LinkedList(); A0M)*9 f
/** Creates a new instance of CountCache */ f&(u[W
public CountCache() {} BpCzmU
public static void add(CountBean cb){ Y.@
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if(cb!=null){ SPL72+S`,
list.add(cb); Tn/
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{
} @5zL4n@w
} xrO:Y!C?
} DJrE[wI
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CountControl.java Y-n*K'
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/* A7-QOqST(
* CountThread.java Qm,|'y:Tg
* Gy
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* Created on 2007年1月1日, 下午4:57 ?YX2CJ6N
* b}o^ ?NtA
* To change this template, choose Tools | Options and locate the template under -U"(CGb5
* the Source Creation and Management node. Right-click the template and choose 6{}]QvR
* Open. You can then make changes to the template in the Source Editor. a)4.[+wnRf
*/ cy?u
*
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package com.tot.count; }9>W41
import tot.db.DBUtils; O~-#>a
import java.sql.*; j*g5f
/** E@R7b(:*
* Oh~JyrZy
* @author W:b8m Xx
*/ A%oHx|PD
public class CountControl{ @xB"9s
private static long lastExecuteTime=0;//上次更新时间 &BCl>^wn}
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 nod?v2%
/** Creates a new instance of CountThread */ a*NcL(OC
public CountControl() {} L=VJl[DL
public synchronized void executeUpdate(){ 1N1MD@C?P
Connection conn=null; B@A3T8'
PreparedStatement ps=null; )O"5dF1l
try{ \$V~kgQ0
conn = DBUtils.getConnection(); F.?^ko9d
conn.setAutoCommit(false); d5\w'@Di
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); W'-B)li
for(int i=0;i<CountCache.list.size();i++){ X&TTw/J!^
CountBean cb=(CountBean)CountCache.list.getFirst(); VW I{ wC
CountCache.list.removeFirst(); {XC# -3O
ps.setInt(1, cb.getCountId()); My76]\Psh
ps.executeUpdate();⑴ g03I<<|@
//ps.addBatch();⑵ =" #O1$
} \eT0d<
//int [] counts = ps.executeBatch();⑶ ga?.7F
conn.commit(); )Pakb!0H@t
}catch(Exception e){ p./zW
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e.printStackTrace(); =m:xf&r#
} finally{ HO/Ij
try{ z^T/kK3I
if(ps!=null) { {PnvQ?|Z
ps.clearParameters(); e]'ui<`
ps.close(); PzWhB* iBR
ps=null; "H" 4(3
} `6)GjZh^
}catch(SQLException e){} .EM0R\q
DBUtils.closeConnection(conn); btJ:Wt}
} #;)Oi9{9;
} %(MaH
public long getLast(){ }Ry:})
return lastExecuteTime; |77.Lqqy,
} "9jt2@<
public void run(){ `|Pfa
long now = System.currentTimeMillis(); [`BMi-WQ
if ((now - lastExecuteTime) > executeSep) { {~_X-g5|]
//System.out.print("lastExecuteTime:"+lastExecuteTime); zt/b S/
//System.out.print(" now:"+now+"\n"); WUm83"
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ~,WG284
lastExecuteTime=now; e;GLPB
executeUpdate(); \
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} {?!=~vp
else{ :hr% 6K7
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9fj3q>Un,
}
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} }:<`L\8q\
} *pK bMG#
//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 Q1yMI8
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类写好了,下面是在JSP中如下调用。 j*+[=X/
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<% <E/4/
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CountBean cb=new CountBean(); z SDRZ!
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); KX D&FDkF
CountCache.add(cb); vik A
out.print(CountCache.list.size()+"<br>"); XVr>\T4
CountControl c=new CountControl(); ]CHO5'%,$
c.run(); *(wkgn
out.print(CountCache.list.size()+"<br>"); w.Cw)#N
%>