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: 30B!hj$C
3:76x
CountBean.java
cvAkP2
%7hYl'83
/* aA\v
* CountData.java |~uCLf>
* RJSNniYr7
* Created on 2007年1月1日, 下午4:44 /dtFB5Z"w
* a}=)b#T`
* To change this template, choose Tools | Options and locate the template under B?Pu0
_|s
* the Source Creation and Management node. Right-click the template and choose EpPKo
* Open. You can then make changes to the template in the Source Editor. M(5l Su
*/ Z}XA(;ck
jgukW7H
package com.tot.count; 1k;X*r#
J/)Q{*`_
/** %"{SGp
* O~igwFe
* @author t*n!kXa
*/ $ABW|r
public class CountBean { r1t TY?
private String countType; c!6.D
int countId; HbV[L)zYG
/** Creates a new instance of CountData */ k}JjSt1_A;
public CountBean() {} B(E+2;!QF
public void setCountType(String countTypes){ DQwbr\xy\
this.countType=countTypes; Xo$(zGb
} esFBWJ
public void setCountId(int countIds){ ?|{P]i?)'
this.countId=countIds; 6J-tcL*4"%
} ~|+
public String getCountType(){ X(N!y"z
return countType; Pq !\6s@
} ALPZc:
public int getCountId(){ k`xPf\^tf
return countId; Dy0RZF4_
} i?||R|>;"'
} 5Vf#(r f
7)<&,BWc
CountCache.java 02?y%
&@nI(PXv
/* n{=vP`V_
* CountCache.java ~#OnA1)
* <Y<%=`
* Created on 2007年1月1日, 下午5:01 ".~,(*
* F d *p3a
* To change this template, choose Tools | Options and locate the template under k${25*M!3
* the Source Creation and Management node. Right-click the template and choose )g+~"&Gcx
* Open. You can then make changes to the template in the Source Editor. 1@;Dn'
*/ "){"{~
P;][i| x
package com.tot.count; $,F1E VJ
import java.util.*; '\=aSZVO
/** `BF +)fs
* ~xkcQ{
* @author -=@d2LY
*/ _KLKa/3
public class CountCache { g2BE-0, R
public static LinkedList list=new LinkedList(); RQ!kVM@
/** Creates a new instance of CountCache */ =J<3B
H^m
public CountCache() {}
c7,p5[
public static void add(CountBean cb){ Qne@Vf kA
if(cb!=null){ bRfac/:}
list.add(cb); o4\\q66K
} yIA-+# r[
} 6|| zfH
} k_/*>lIZY
'de&9\
CountControl.java ?sk{(UN]
Y2W|b5
/* }k~ih?E^s
* CountThread.java ;M1# M:
* +9<"Y6
* Created on 2007年1月1日, 下午4:57 }&F|u0@b
* mA@FJK_
* To change this template, choose Tools | Options and locate the template under ?^n),mR
* the Source Creation and Management node. Right-click the template and choose T1_O~<
* Open. You can then make changes to the template in the Source Editor. 4hz T4!15
*/ P XKEqcQR
QVJq% P
package com.tot.count; ,` 6O{Z~
import tot.db.DBUtils; 2Jo|]>nl}u
import java.sql.*; kNR -eG
/** F2QFQX(j
* ~}pc&jz>q
* @author _Dr9 w&;<
*/ 8BE] A_X
public class CountControl{ k#liYw I
private static long lastExecuteTime=0;//上次更新时间 L `NY^
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ,)@njC?J
/** Creates a new instance of CountThread */ uGOED-@
public CountControl() {} 3:C)1q
public synchronized void executeUpdate(){ Ra)wlIx
Connection conn=null; %<8`(Uu5
PreparedStatement ps=null; SMoJKr(:w#
try{ rP|~d}+I
conn = DBUtils.getConnection(); #9zpJ\E
conn.setAutoCommit(false); Swa0TiT(
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Ql"kJ_F!br
for(int i=0;i<CountCache.list.size();i++){ )0+6^[Tqq
CountBean cb=(CountBean)CountCache.list.getFirst(); `i`+yh>pc#
CountCache.list.removeFirst(); `%; Hj _X}
ps.setInt(1, cb.getCountId()); $>Qq 7
ps.executeUpdate();⑴ g&z8t;@
//ps.addBatch();⑵ ,4:=n$e 0
} ' Dp;fEU$
//int [] counts = ps.executeBatch();⑶ o=J-Ju
conn.commit(); %
bfe_k(
}catch(Exception e){ d^MRu#]
e.printStackTrace(); J?{@pA
} finally{ _Ne fzZWUJ
try{ :aQ.:b(n
if(ps!=null) { mC2K &'[
ps.clearParameters(); ~(nc<M[
ps.close(); 76H>ST@G|
ps=null; 7-:R{&3Lm:
} l^F ?^kP
}catch(SQLException e){} dq,j?~ _}
DBUtils.closeConnection(conn); Yw] 7@
} plL|Ubn
}
J-#V_TzJ?
public long getLast(){ wg%g(FO
return lastExecuteTime; &hEn3u
} % IHIXncv[
public void run(){ "!+gA&
long now = System.currentTimeMillis(); <Pzy'9
if ((now - lastExecuteTime) > executeSep) { Lq|>n[KY
//System.out.print("lastExecuteTime:"+lastExecuteTime); J3 `0i@
//System.out.print(" now:"+now+"\n"); :of(wZa3Q
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); Hz\@#
lastExecuteTime=now; |Dt_lQp#
executeUpdate(); (\0
<|pW
} Nv=78O1
else{ jc!m; U t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); CYRZ2Yrk?"
} U0gZf5;*
} #u}%r{T
} t0+i]lr
//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 K!]a+M]>
Q$uv
\h;
类写好了,下面是在JSP中如下调用。 Kci. ,I
G54J'*Z
<% `78Bv>[A
CountBean cb=new CountBean(); ~)^'5^
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); 8N%nG(
0
CountCache.add(cb); |BbzRis
out.print(CountCache.list.size()+"<br>"); dvZH ~mF
CountControl c=new CountControl(); `^52IkM)
c.run(); AtewC
Yo
out.print(CountCache.list.size()+"<br>"); D|)a7_
%>