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: 6;DPGx
eU0-_3gN_
CountBean.java [5-5tipvWp
v8[1E>&vx
/* $%'z/'o!
* CountData.java rG6/h'!|
* ^DOcw@Z6HC
* Created on 2007年1月1日, 下午4:44 FW,D\51pTP
* Y@eUvz
* To change this template, choose Tools | Options and locate the template under L&%iY7sC`
* the Source Creation and Management node. Right-click the template and choose HVpaVM
* Open. You can then make changes to the template in the Source Editor. 6h%(0=^
*/ CTYkjeej
4{pa`o3
package com.tot.count; g<Xwk2_=g
2}-W@R
/** d8I/7
;F X
* }z#8vE;
* @author 5[k35c{
*/ \;<Y/sg
public class CountBean { DSp@
private String countType; >%,tyJ~
int countId; W#Z]mt B
/** Creates a new instance of CountData */ tK*f8X+q
public CountBean() {} ^=j$~*(LmX
public void setCountType(String countTypes){ lVHJ}(<'p
this.countType=countTypes; WP9=@X Z
} :C5N(x
public void setCountId(int countIds){ 7_,X9^z
this.countId=countIds; crQuoOl7
} eNX-2S
public String getCountType(){ hv6>3gbr
return countType; ;a"Ukh
} YQOGxSi
public int getCountId(){ h?sh#j6
return countId; c-F&4V
} >8so'7(
} YuZnuI@m9
)C[8#Q-:
CountCache.java ]Az >W*Y
QG.FW;/L,
/* HO>uS>+
* CountCache.java !*;)]j
* "rtmDNpL
* Created on 2007年1月1日, 下午5:01 5h&8!!$[
* ;A_QI>>
* To change this template, choose Tools | Options and locate the template under 42M3c&@P
* the Source Creation and Management node. Right-click the template and choose &x3y.}1
* Open. You can then make changes to the template in the Source Editor. x8[8z^BV?e
*/ pH%K4bV)8
gd*\,P
package com.tot.count; 4-MA!&
import java.util.*; ;FUd.vg{
/** n"JrjvS
* _
i8}ld-
* @author 9Z=Bs)-y.
*/ Y`wi=(
public class CountCache { WG,{:|!E
public static LinkedList list=new LinkedList(); IaB
A 2
/** Creates a new instance of CountCache */ /dAIg1ra
public CountCache() {} YL]x>7T~4t
public static void add(CountBean cb){ /D12N'VaE
if(cb!=null){ VCI G+Gz
list.add(cb); DIY WFVh
} YG_3@`-<
} YAO0>T<F
} 97lwPjq
:3k(=^%G!
CountControl.java *-7O|
''
` WVQp"m
/* R[b?kT-%
* CountThread.java AbB%osz}Ed
* >. A{=?
* Created on 2007年1月1日, 下午4:57 +.=a
R<Q
* kci H
* To change this template, choose Tools | Options and locate the template under `k+k&t
* the Source Creation and Management node. Right-click the template and choose y(HR1vQ;Z
* Open. You can then make changes to the template in the Source Editor. q(C+D%xB
*/ %}@^[E)
&\A$Rj)
package com.tot.count; j JW0a\0
import tot.db.DBUtils; x|Dj
import java.sql.*; S}>rsg!
/** lp6GiF
* IzG7!K
* @author i<l)To -
*/ 1t6UI4U!$
public class CountControl{ X- zg
private static long lastExecuteTime=0;//上次更新时间 vR -/c
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 $ysC)5q.
/** Creates a new instance of CountThread */ iVD9MHT4
public CountControl() {} 83@+X4ptp
public synchronized void executeUpdate(){ !e?\>
'
Connection conn=null; (g 8K?Q
PreparedStatement ps=null; ?/;<32cE,
try{ T"$"`A"
conn = DBUtils.getConnection(); n[<Vj1n
conn.setAutoCommit(false); {d)+a$qj
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); {2,V3*NF
for(int i=0;i<CountCache.list.size();i++){ LWY`J0/
CountBean cb=(CountBean)CountCache.list.getFirst(); MSA*XDnN
CountCache.list.removeFirst(); M/BBNT
ps.setInt(1, cb.getCountId()); O!a5
ps.executeUpdate();⑴ h5~tsd}OU
//ps.addBatch();⑵ W>Zce="_gN
} ?wmr~j
//int [] counts = ps.executeBatch();⑶ |XQ!xFB
conn.commit(); '1d-N[
}catch(Exception e){ |
#,b1|af
e.printStackTrace(); 18Ty)7r'
} finally{ $
_ gMJ\{
try{ $]O\Ryf6
if(ps!=null) { :g Ze>
ps.clearParameters(); &.d~
M1Mz
ps.close(); aFLm,
ps=null; JV@>dK8
} R \iU)QP
}catch(SQLException e){} -IPc;`<
DBUtils.closeConnection(conn); 2rA`y8g(L
} 9khD7v
} hNQ,U{`;^
public long getLast(){ 6 ,k}v:
return lastExecuteTime; P", 53R+"
} EPyFM_k
public void run(){ rK];2[U
long now = System.currentTimeMillis(); u+hzCCwtR
if ((now - lastExecuteTime) > executeSep) { T\OLysc
//System.out.print("lastExecuteTime:"+lastExecuteTime); k+&| *!j
//System.out.print(" now:"+now+"\n"); %hY+%^k.
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); }lhJt|q c
lastExecuteTime=now; 8G9V8hS1#B
executeUpdate(); BH=vI<D
} 1<lLE1fk
else{ Nj?,'?'O}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); <#:"vnm$j
} gX);/;9mm+
} 3dXyKi
} )
~X\W\
//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 pmfyvkLS
C0'Tua'
类写好了,下面是在JSP中如下调用。 GMFp,Df
++xEMP)
<% KVJiCdg-
CountBean cb=new CountBean(); DI+kO(S
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); -BR&b2
CountCache.add(cb); Ucv-}oa-?
out.print(CountCache.list.size()+"<br>"); HZR~r:_
i
CountControl c=new CountControl(); NX$$4<A1
c.run(); \s[Uq
out.print(CountCache.list.size()+"<br>"); F`f#gpQ
%>