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: j<)$ [v6
!XjZt
CountBean.java <t!0{FJ
%"c;kvw
/* Mu:zWLM*M
* CountData.java Ep;?%o ,G
* jTqJ(M}L
* Created on 2007年1月1日, 下午4:44 indbg
d
* c{to9Lk.#
* To change this template, choose Tools | Options and locate the template under ~X2# z|
* the Source Creation and Management node. Right-click the template and choose ~)$R'=
* Open. You can then make changes to the template in the Source Editor. k>MXOUaW.
*/ jqvw<+#
L-U4
8 i
package com.tot.count; p`&{NR3+
?>ZrdfTwz,
/** 7>@0nHec
* 20$Tky_
* @author GD}rsBQNkJ
*/ 8?m=Vw<kIZ
public class CountBean { ubZuvWZ
private String countType; 4MDVR/Z7
int countId; p cUccQ
/** Creates a new instance of CountData */ +KExK2=
public CountBean() {} 3,i`FqQa
public void setCountType(String countTypes){ Y:+:>[F
this.countType=countTypes; MY\mo,#
} ZTqt 4H
public void setCountId(int countIds){ $l.8
this.countId=countIds; IeChz d
} ,1|=_M31
public String getCountType(){ X`v6gv5qj
return countType; (/&ht-~EL
} Q ijO%)
public int getCountId(){ SK/}bZ;f
return countId; t3}_mJ
} #,lbM%a
} \QSD*
~ cu+QR)
CountCache.java 2>x[_
%NlmLWF.
/* SmyJ@.L"
* CountCache.java >d
.|I&
* _u_|U
* Created on 2007年1月1日, 下午5:01 ](-[
I#
* v{lDEF@2^N
* To change this template, choose Tools | Options and locate the template under nx`W!|g$`
* the Source Creation and Management node. Right-click the template and choose lr)MySsu#H
* Open. You can then make changes to the template in the Source Editor. z-0
N/?x1
*/ t':*~b{V@7
jMR9E@>~E
package com.tot.count; ]+^4Yq>2
import java.util.*; [KO\!u|?YS
/** |%X_<Cpk
* ss|n7
* @author xXV15%&
*/ \sVzBHy d
public class CountCache { },5LrX`L
public static LinkedList list=new LinkedList(); [A!=Hv_$
/** Creates a new instance of CountCache */ W^:g_
public CountCache() {} 6xh-m
public static void add(CountBean cb){ XxB%
if(cb!=null){ |QH )A
list.add(cb); 7S&O{Q7)
} bw#\"uJ
} }LIf]YK
} zS?}3#g0u
lg (>n&
CountControl.java ]%Whtj.,x7
VJgf,
5 (N
/* /oM&29 jy
* CountThread.java ~fgS"F^7n
* ,tBc%&.f
* Created on 2007年1月1日, 下午4:57 b;mpZ|T.
* WIwGw %_~
* To change this template, choose Tools | Options and locate the template under X~; *zYd5
* the Source Creation and Management node. Right-click the template and choose ;P|v'NNI
* Open. You can then make changes to the template in the Source Editor. l_q1h]/
*/ oFGgr2Re
:SD3
package com.tot.count; eLN(NSPoS
import tot.db.DBUtils; xdsF! Zb
import java.sql.*; q=BAYZ\`
/** cz>`$Zz
* "Jyb?5
* @author y3V47J2o
*/ t&bE/i_T
public class CountControl{ #0qMYe>Y
private static long lastExecuteTime=0;//上次更新时间 exm*p/
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 R&R{I/;i*.
/** Creates a new instance of CountThread */ Q},uM_"+
public CountControl() {} f V/
public synchronized void executeUpdate(){ LTD;
Connection conn=null; <8Q?kj
PreparedStatement ps=null; H&ZsMML/%
try{ '&xRb*
conn = DBUtils.getConnection(); 6^p>f:5
conn.setAutoCommit(false); v".u#G'u
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ##NowO
for(int i=0;i<CountCache.list.size();i++){ @)@hzXQ
CountBean cb=(CountBean)CountCache.list.getFirst(); !. ={p8X-x
CountCache.list.removeFirst(); 9c@\-Z'
ps.setInt(1, cb.getCountId()); lFM'F [-?-
ps.executeUpdate();⑴ bzMs\rj\
//ps.addBatch();⑵ "l09Ae'V
} oxqD/fY
//int [] counts = ps.executeBatch();⑶ dG]s_lb9H
conn.commit(); 5HbPS%^.
}catch(Exception e){ Vuo 8[h>
e.printStackTrace(); n)teX.ck)
} finally{ A832z`
try{ K*
0]*am|v
if(ps!=null) { m4T`Tg#P
ps.clearParameters(); w`0r`\#V/
ps.close(); G|]39/OO3{
ps=null; 6sRKbp|r7
} h<2O+"^
}catch(SQLException e){} <~qhy{hRn
DBUtils.closeConnection(conn); =:'a)o
} N`rOlEk
} i_;]UvP
public long getLast(){ *8QGv6*vQ
return lastExecuteTime; n1)m(,{
} ,7Lu7Q
public void run(){ ~dqEUu!C
long now = System.currentTimeMillis(); *(@[E
if ((now - lastExecuteTime) > executeSep) { rU1{a" {
//System.out.print("lastExecuteTime:"+lastExecuteTime); $y*["~TJ
//System.out.print(" now:"+now+"\n"); ma M8:\
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); %g&i.2v
lastExecuteTime=now; -@_V|C'?
executeUpdate(); S)\%.~ n
} ep"54o5=d
else{ #6<9FY#
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); 9Lxj
]W2^
} ]hkway
} NCysYmt
} Ijj]_V{,
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 9Ic~F^
5zBsu lRt
类写好了,下面是在JSP中如下调用。 ~cx/>Hu
7[ra#>e8'
<% X[c8P7
CountBean cb=new CountBean(); mI~k@ !3
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H0B"?81
CountCache.add(cb); NLxsxomj
out.print(CountCache.list.size()+"<br>"); 3$`qy|=zO
CountControl c=new CountControl(); Ea*Jl<
c.run(); V qW(S1w
out.print(CountCache.list.size()+"<br>"); GzUgzj|BN~
%>