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: O/XG}G.x|
AvmI<U
CountBean.java ABx< Ep6
l|kGp~
/* 3_DwqZ 'O
* CountData.java _p^?_
* Vn=K5nm
* Created on 2007年1月1日, 下午4:44 539fB,
* GhJ<L3
* To change this template, choose Tools | Options and locate the template under B*OEG*t
* the Source Creation and Management node. Right-click the template and choose ?&`PN<~2z
* Open. You can then make changes to the template in the Source Editor. +g9CklJ
*/ ^P!(*k#T
N*1{yl76x
package com.tot.count; V}Ok>6(~
whW%c8
/** .OM^@V~T
* r!N> FE
* @author 5i0vli/L
*/ }R9>1u}6
public class CountBean { Hhzi(<e^
private String countType; *^3&Y@
int countId; kgb:<{pJ
/** Creates a new instance of CountData */ CcJ%;.V,T
public CountBean() {} a5k![sw\
public void setCountType(String countTypes){ V;LV),R?
this.countType=countTypes; b Y2:g )
}
N Zu2D
public void setCountId(int countIds){ Z~3
this.countId=countIds; Q{o ]^tN
} Z[G[.\0
public String getCountType(){ =h>jo&=Wad
return countType; 9dO. ,U*`
} 7~qyz]KkE
public int getCountId(){ Yq-Vwh/
return countId; {9XN\v=$"*
} ?APCDZ^
} &SW~4 {n:
pwg\b
CountCache.java ]<BT+6L
8b[<:{[YB
/* grxlGS~Q
* CountCache.java sTu]C +A
* u.@B-Pf[Eo
* Created on 2007年1月1日, 下午5:01 x+bC\,q
* @@3%lr71
* To change this template, choose Tools | Options and locate the template under w }=LC#le
* the Source Creation and Management node. Right-click the template and choose h:=W`(n5u
* Open. You can then make changes to the template in the Source Editor. {+^&7JX
*/ AsfmH-4)
._[uSBR'
package com.tot.count; Zs|m_O G
import java.util.*; (:>Sh0.
/** 3rj7]:Vr
* 8\S$iGd
* @author @:/H)F^x
*/ IMSLHwZ
public class CountCache { T0X+\&W
public static LinkedList list=new LinkedList(); Oj>;[O"
/** Creates a new instance of CountCache */ 2dCD.9s9~
public CountCache() {} EX/{W$
&K
public static void add(CountBean cb){ sZ>0*S
if(cb!=null){ 6Qn};tbnD
list.add(cb); ?s@=DDB\u
} blKF78
} ]64pb;w"$D
} n
>@Qx$-
ROJ=ZYof
CountControl.java cKB1o0JsYJ
ckkm}|&m
/* ID~}pEQ
* CountThread.java g!;a5p6
* zwJ\F '
* Created on 2007年1月1日, 下午4:57 he|.Ow
* }2''}-Nc
* To change this template, choose Tools | Options and locate the template under 0V+v)\4FE
* the Source Creation and Management node. Right-click the template and choose !8*7 {7
* Open. You can then make changes to the template in the Source Editor. r-AD*h@QZ
*/ y[';@t7CC
.1:B\R((
package com.tot.count; e3k58
import tot.db.DBUtils; r8Z.}<j
import java.sql.*; CsJ&,(s(
/** EvptGM
* y`Zn{mQ@[
* @author kA/yL]m^S
*/ 6lm<>#_
public class CountControl{ moCR64n
private static long lastExecuteTime=0;//上次更新时间 I`nC\%g
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 YRyaOrl$<
/** Creates a new instance of CountThread */ skF}_
public CountControl() {} fuT Bh6w&
public synchronized void executeUpdate(){ a(AYY<g
Connection conn=null; /<k]mY cu
PreparedStatement ps=null; 9z+ZFIf7d
try{ g f<vQb|
conn = DBUtils.getConnection(); C$d b)5-
conn.setAutoCommit(false); 1 fTf+P
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); WJ/X`?k
for(int i=0;i<CountCache.list.size();i++){ !8|?0>3)
CountBean cb=(CountBean)CountCache.list.getFirst(); K?Jo"oy7
CountCache.list.removeFirst(); `(xzCRX
ps.setInt(1, cb.getCountId()); ]VaMulb4
ps.executeUpdate();⑴ Uka(Vr:
//ps.addBatch();⑵ sn8l3h)
} J;N\q
//int [] counts = ps.executeBatch();⑶ L]E.TvM1*
conn.commit(); oxug
}catch(Exception e){ L|p+;ex
e.printStackTrace(); EUbyQL
} finally{ Bo;{ QoB
try{
E-deXY
if(ps!=null) { ,+v>(h>q
ps.clearParameters(); ^;[^L=}8$
ps.close(); jd.w7.8
ps=null; rQ(u@u;
} C[CNJ66
}catch(SQLException e){} $ve*j=p
DBUtils.closeConnection(conn); PY#_$ C
} >]x%+@{|
} hX:yn:P~
public long getLast(){ sj&1I.@,>
return lastExecuteTime; k{ulu
} &kQj)
public void run(){ P"|-)d
long now = System.currentTimeMillis(); |Y30B,=M
if ((now - lastExecuteTime) > executeSep) { ^nLk{<D35
//System.out.print("lastExecuteTime:"+lastExecuteTime); )BZ6QO`5n
//System.out.print(" now:"+now+"\n"); >$7{H]
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); ,WE2MAjhT
lastExecuteTime=now; 1]&{6y
executeUpdate(); NCVhWD21|
} C8 y[B1Y
else{ 4!A(7
s4t
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 7*r!-$
} 0GQKM~|H
} 7 iQa)8,
} qmtH0I7)
//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 YoSBS
'M
fVZho{
类写好了,下面是在JSP中如下调用。 \)cbg#v
{6mFI1;q
<% >gDKkeLD
CountBean cb=new CountBean(); j2oU1' b
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); p-h(C'PqF
CountCache.add(cb); PJAM_K;
out.print(CountCache.list.size()+"<br>"); K/$5SN1
CountControl c=new CountControl(); {Hz;*1?$k
c.run(); T3t
w.yh
out.print(CountCache.list.size()+"<br>"); QG5c>Q
%>