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: &H8wYs
2[~|#0x
CountBean.java Em)U`"j/9
"| Oj!&0
/* pHQrjEF*
* CountData.java +7\$wc_1I@
* g)$/'RB
* Created on 2007年1月1日, 下午4:44 \]C_ul'
* "uCO?hv0
* To change this template, choose Tools | Options and locate the template under -yOwX2Wv5;
* the Source Creation and Management node. Right-click the template and choose b S-o86u
* Open. You can then make changes to the template in the Source Editor. m%zo? e
*/ 3LGX ^J<f
_U.|$pU
package com.tot.count; i(T[
`-t8ag3
/** !LI6_Oq
* )5T82=[h<
* @author wcH,!;3z+
*/ GDF/0-/Z
public class CountBean { aeZ$Wu>]W
private String countType; ')N[)&&Q{
int countId; 1WjNF i
/** Creates a new instance of CountData */ @k=UB&?I
public CountBean() {} (4o<U%3kGq
public void setCountType(String countTypes){ &!P' M
this.countType=countTypes; fGZ56eH:
} &Va="HNKt
public void setCountId(int countIds){ W(pq_H'
this.countId=countIds; .~$!BWP
} Z8C~o)n9
public String getCountType(){ l266ufO.u-
return countType; tGE=!qk
} Cj%n?-
public int getCountId(){ %xt;&HE
return countId; Q,nJz*AJ
} nuKcq!L
} "@z X{^:
[ Y+Ta,
CountCache.java :@uIEvD?
O22Q
g
/* e,kxg^
* CountCache.java 6ChFsteGFr
* r7)qr%n
* Created on 2007年1月1日, 下午5:01 p{
Xde
* ziDvDu=
* To change this template, choose Tools | Options and locate the template under R
+
~b@
* the Source Creation and Management node. Right-click the template and choose = N&5]Z
* Open. You can then make changes to the template in the Source Editor. SzP`(}AU
*/ uMx6:
!"2S'oQKS
package com.tot.count; OZc4 -5
import java.util.*; }y%c.
/** J>l?HK
* apOXcZ
* @author xKR\w!+Z'
*/ &(7=NAQsE
public class CountCache { dI%?uk
public static LinkedList list=new LinkedList(); 6k_Uq.<X
/** Creates a new instance of CountCache */ SR$ 'JGfp
public CountCache() {} p}oGhO&=
public static void add(CountBean cb){ /4*Y#IpZ
if(cb!=null){ [rkw k\m*
list.add(cb); !4-4i
} @)\4 $#+-
}
|nCVM\+5T
} u,V_j|(e
_tUh*"e&
CountControl.java \q($8<
{xAd>fGG+y
/* vPz$+&{I
* CountThread.java Y-UXr8
* gw!d[{#
* Created on 2007年1月1日, 下午4:57 TZ63=m
* JM1O7I
* To change this template, choose Tools | Options and locate the template under bwM?DY
* the Source Creation and Management node. Right-click the template and choose ]]0Yh
* Open. You can then make changes to the template in the Source Editor. PYBE?td
*/ Fc#Sn2p*
@U3:9~Q
package com.tot.count; {dXTj 7
import tot.db.DBUtils; T>f6V 5
import java.sql.*; Ol B9z
/** dz?On\66
* z&cM8w:
* @author 7Db}bDU1
|
*/ k#bG&BF
public class CountControl{ FDFwx|
private static long lastExecuteTime=0;//上次更新时间 0kSM$D_
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 MuJP.]5>`
/** Creates a new instance of CountThread */ %s497'
public CountControl() {} a:8 MoH 4
public synchronized void executeUpdate(){ ;4U"y8PVTh
Connection conn=null; m]vS"AdX
PreparedStatement ps=null; m/Erw"Z
try{ hq&|
conn = DBUtils.getConnection(); "~=-Q#xO
conn.setAutoCommit(false); Nm
!~h|3
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); RIQ-mpg~(k
for(int i=0;i<CountCache.list.size();i++){ [GPCd@
CountBean cb=(CountBean)CountCache.list.getFirst(); y XKddD
CountCache.list.removeFirst(); CY*o"@-o5)
ps.setInt(1, cb.getCountId()); -)Bvx>8fq-
ps.executeUpdate();⑴ iO&*WIbg
//ps.addBatch();⑵ #i.,+Q
} ,PmUl=
//int [] counts = ps.executeBatch();⑶ Nc&J%a
conn.commit(); %3O))Ug5
}catch(Exception e){ ,{mv6?_
e.printStackTrace(); m}u)C&2>
} finally{ q}+zNeC
try{ _1Q6FI5iR
if(ps!=null) { IMr#5
ps.clearParameters(); F^$;hMh%
ps.close(); n$N$OFuO
ps=null; Fgi`g{N
} }K8e(i6z
}catch(SQLException e){} LPBa!fq
DBUtils.closeConnection(conn); Ui!l3_O
} tAE(`ow/Ur
} 5JhvYsf3_
public long getLast(){ HdgNy \
return lastExecuteTime; x!fG%o~h
} "w$,`M?2
public void run(){ ?m5EXe
long now = System.currentTimeMillis(); *L9v(Kc
if ((now - lastExecuteTime) > executeSep) { ~|9VVeE
//System.out.print("lastExecuteTime:"+lastExecuteTime); #CPLvg#
//System.out.print(" now:"+now+"\n"); 7UY4* j|[C
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); 'da
'WZG
lastExecuteTime=now; pmUf*u-
executeUpdate(); YGC%j
} =Q{?!
else{ 3<Zp+rD
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); xu_,0ZT]{
} O^3kPVr
} [al$sCD]+
} (:qc[,m
//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 r88De=*
`<yQ`Y_X
类写好了,下面是在JSP中如下调用。 Cdib{y<ji
0Dna+V/jI
<% g9q}D-
CountBean cb=new CountBean(); y] c1x=x
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); hVmnXT
3Z
CountCache.add(cb); t"Ci1"U
out.print(CountCache.list.size()+"<br>"); En1LGi4#
CountControl c=new CountControl(); u -P !2vT
c.run(); 'prHXzi(h
out.print(CountCache.list.size()+"<br>"); %0} ^M1
%>