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: 6A<aelE*i
7EUaf;d^
CountBean.java $TiAJ}:
_GS2&|7`
/* F);C?SW"
* CountData.java 7Uh}|6PU
* @g{
"
E6
* Created on 2007年1月1日, 下午4:44 1Y_fX
* [dUEe@P
* To change this template, choose Tools | Options and locate the template under l"64w>,
* the Source Creation and Management node. Right-click the template and choose HukHZ;5
* Open. You can then make changes to the template in the Source Editor. 0Pe.G0 #
*/ ZsE8eD
x<" e
package com.tot.count; ?hO*~w;UU|
UqH7e c
/** #gq3 e
* am=56J$ig
* @author *|'k
*/ iw%DQ }$
public class CountBean { mcvTz, ;=
private String countType; [Z 1Eje X
int countId; K%;O$
>
/** Creates a new instance of CountData */ Eyuc~[
public CountBean() {} ,QDq+93
public void setCountType(String countTypes){ H74hv`G9
this.countType=countTypes; 0x84 Ah)
} 8164SWB
public void setCountId(int countIds){
/YHeO
this.countId=countIds; j_Fr3BWS
} XHV+Y+VG
public String getCountType(){ 1BF+sT3
return countType; 0kDT:3
} S5;q)qz2J
public int getCountId(){ 3|C"F-'<
return countId; K_xn>
} B$HQFdTli
} 8`+X6iZOQ
Sng V<J>zR
CountCache.java 0\/7[nwS
/H)l\m
+
/* 3' ^ON
* CountCache.java cWm.']
* ]uP{Sj
* Created on 2007年1月1日, 下午5:01 R1U\ /
* iS{)Tll}&
* To change this template, choose Tools | Options and locate the template under H_x35|"
* the Source Creation and Management node. Right-click the template and choose bF3j* bpO"
* Open. You can then make changes to the template in the Source Editor. uzsR*x%s-
*/ s;A]GJ
q.*qZ\;K
package com.tot.count; \]^|IViIQ
import java.util.*; ,y^By_1wS
/** ]M_)f
* Vi]D](^!
* @author RD~QNj9,T
*/ z*FlZLHY
public class CountCache { ]O 2_&cs
public static LinkedList list=new LinkedList(); T_r[#j
/** Creates a new instance of CountCache */ *rWE.4=&
public CountCache() {} 0KEytm]
public static void add(CountBean cb){ q.#aeqKBP
if(cb!=null){ Od"-w<'
list.add(cb); "~GudK &
} 3#dUQ1qo6
} 'oo]oeJ-
} Cu>pql<O
k(Ow.nkb
CountControl.java
-"<eq0
;e-iiC]PI
/* L%fWa2P'
* CountThread.java NvYgRf}uh
* ,TL~];J'
* Created on 2007年1月1日, 下午4:57 {C
7=
* ]RxNSr0e
* To change this template, choose Tools | Options and locate the template under #Qkl| h
* the Source Creation and Management node. Right-click the template and choose CnAh Ef)b
* Open. You can then make changes to the template in the Source Editor. 5e/%Tue.
*/ j J9|
EQg
6*V
package com.tot.count; o#;w>-
import tot.db.DBUtils; 1W5YS +pf
import java.sql.*; cZ5[A T
/** 2t_E\W7w+
* B^eea [
* @author +1e*>jE
*/ g-6!+>w*>e
public class CountControl{ 2-2'c?%
private static long lastExecuteTime=0;//上次更新时间 ?
[=P
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Oyz=|[^,W
/** Creates a new instance of CountThread */ cLamqZf3
public CountControl() {} MECR0S9
public synchronized void executeUpdate(){ 7 0KZXgBy_
Connection conn=null; rsrv1A=t?
PreparedStatement ps=null; .3$iOMCH
try{ jk) U~KGcg
conn = DBUtils.getConnection(); zS.7O'I<'
conn.setAutoCommit(false); ZWYwVAo
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); d`^j\b>5(
for(int i=0;i<CountCache.list.size();i++){ }P^{\SDX
CountBean cb=(CountBean)CountCache.list.getFirst(); H.'_NCF&;L
CountCache.list.removeFirst(); Lc+)#9*d
ps.setInt(1, cb.getCountId()); -6#i~a]
ps.executeUpdate();⑴ /Z\zB
//ps.addBatch();⑵ I_v]^>Xw
} 8 #0?
//int [] counts = ps.executeBatch();⑶ _QCAV+K'
conn.commit(); eQzTb91
}catch(Exception e){ s9@IOE GAt
e.printStackTrace(); dBCg$Rud&
} finally{ (/PD;R$b
try{ 6Ba>l$/q
if(ps!=null) { @Yy=HV
ps.clearParameters(); ;u, 5
2
ps.close(); ;b(/PH!O
ps=null; B,}%1+*
} YAsvw\iseK
}catch(SQLException e){} )\p@E3Uxf
DBUtils.closeConnection(conn);
T<P4+#JK
} _)lK.5
} DAJh9I
public long getLast(){ 'M YqCfIK
return lastExecuteTime; _Tev503
} }K0.*+M
public void run(){ O=ci"2!\-
long now = System.currentTimeMillis(); ](^VEm}w;
if ((now - lastExecuteTime) > executeSep) { ==Ju2D?%
//System.out.print("lastExecuteTime:"+lastExecuteTime); f'*HP%+Y
//System.out.print(" now:"+now+"\n"); >[ywrB ?T
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); PLwa!j
lastExecuteTime=now; ?DM-C5$
executeUpdate(); dDAdZxd
} cND2(<jx:
else{ Wu%;{y~#}
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); G| ^tqI
} Xo }w$q5
}
,8@@r7
} B-JgXW.\0
//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 CfA
F.H
S =eP/
类写好了,下面是在JSP中如下调用。 *9*6n\~aI
">NBPanJ
<% 'Zk&AD ~
CountBean cb=new CountBean(); n6
)
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); ptYQP^6S[
CountCache.add(cb); 7-bU9{5
out.print(CountCache.list.size()+"<br>"); Yr!<O&=
CountControl c=new CountControl(); wN"irXG
c.run(); BB=%tz`B
out.print(CountCache.list.size()+"<br>"); QZ%_hvY[%>
%>