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: ~J1UzUxX2
3\?yjL^
CountBean.java 6;}W)S
0?,%B?A8O
/* ?[hkh8|
* CountData.java 90
pt'Jg
* ~=c[?:
* Created on 2007年1月1日, 下午4:44 I~>Ye<g#
*
+`~kt4W
* To change this template, choose Tools | Options and locate the template under 6F?U:N#<
* the Source Creation and Management node. Right-click the template and choose j7=x&)qbx
* Open. You can then make changes to the template in the Source Editor. zy@
nBi^
*/ dJ=z'?|%g
tQ(gB_
package com.tot.count; 2~!+EH
&&|c-mD+*
/** T']G:jkb
* I:o.%5)
* @author pa6-3c
*/ F)uS2
public class CountBean { c~n:xblv
private String countType; <):= mr7
int countId; ;
Ne|H$N
/** Creates a new instance of CountData */ j%Z%_{6Ds*
public CountBean() {} S!.H _=z%p
public void setCountType(String countTypes){ fqD1Ej
this.countType=countTypes; JX2@i8[~
} +IbQVU~/
public void setCountId(int countIds){ ivP#qM1*;
this.countId=countIds; eW;0{P
} p7]V1w :
public String getCountType(){ sEEyN3 N
return countType; wT^Q O^.
} S,^)\=v
public int getCountId(){ hH=}<@z
return countId; qku!Mg
} @SH$QUM(
} Wt9'-"c
7G
&I]>
CountCache.java Huho|6ohH
629#t`W\
/* K|sx"u|?
* CountCache.java y[I)hSD=
* ^Z:qlYZ
* Created on 2007年1月1日, 下午5:01 *waaM]u
* H4IJLZ3G
* To change this template, choose Tools | Options and locate the template under 61&A`
* the Source Creation and Management node. Right-click the template and choose 4Y4QR[>IU3
* Open. You can then make changes to the template in the Source Editor. U|)CZcM
*/ _Rm1-,3
Ce!xa\
package com.tot.count; '(yjq<
import java.util.*; ;wj8:9
;
/** QX|y};7\e
* <~-cp61z;
* @author =.8fES
*/ NKE,}^C
public class CountCache { N9gbj%+
public static LinkedList list=new LinkedList(); ynU20g
/** Creates a new instance of CountCache */ GilmJ2<
public CountCache() {} o@A|Lm.
public static void add(CountBean cb){ #m36p+U
if(cb!=null){ S[I-Z_S
list.add(cb); }J|Pd3Q Sf
} 8;1,saA_9
} 1_6oM/?'
} y#)ad\
?S~j2 J]
CountControl.java kr>H,%3~
p1B~F
/* 2 s<uT
* CountThread.java Zsx\GeE%:
* {~+o+LV
* Created on 2007年1月1日, 下午4:57 C`r{B.t`GT
*
ZBl!7_[_
* To change this template, choose Tools | Options and locate the template under pkT26)aW
* the Source Creation and Management node. Right-click the template and choose U@<]>.$
* Open. You can then make changes to the template in the Source Editor. U6yZKK
*/ ud:5_*
(bo-JOOdY(
package com.tot.count; qB8R4wCf
import tot.db.DBUtils; dE]yb|Ld
import java.sql.*; ?)?}^
/** #Zt(g( T
* xmBGZ4f%
* @author B4 +A
*/ XCUU(H
public class CountControl{ ^QTtCt^:
private static long lastExecuteTime=0;//上次更新时间 4g^Xe-
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 ]@9ZUtU,;N
/** Creates a new instance of CountThread */ Y]])Tq;h5
public CountControl() {} uo[W|Q
public synchronized void executeUpdate(){ ,AEaW
Connection conn=null; k5/W'*P
PreparedStatement ps=null; UTR`jXCg
try{ 5!*@gn
conn = DBUtils.getConnection(); Z[?zaQ$
conn.setAutoCommit(false); 1&#qq*{
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); $Z[W}7{pt#
for(int i=0;i<CountCache.list.size();i++){ )H|cri~D
CountBean cb=(CountBean)CountCache.list.getFirst(); a5nA'=|}i
CountCache.list.removeFirst(); FoB^iA6e
ps.setInt(1, cb.getCountId()); gvu1
ps.executeUpdate();⑴ l[u=_uaYl
//ps.addBatch();⑵ o*
C_9M
} .LA?2N
//int [] counts = ps.executeBatch();⑶ zyPc<\HoK
conn.commit(); {?hpW+1,#
}catch(Exception e){ Ic')L*i7O
e.printStackTrace(); 9L9qLF5 t
} finally{ g8L{xwx<
try{ ?3Y~q;I]O
if(ps!=null) { EEdU\9DH(
ps.clearParameters(); SKeX~uLz
ps.close(); s>c0K@ADO
ps=null; 3*!w c.=
} c4Wl^E8
}catch(SQLException e){} ?{rpzrc!*
DBUtils.closeConnection(conn); cbaa*qoU
} $i]G'fj
} ViYfK7Z
public long getLast(){ Vh'H =J
return lastExecuteTime; SBh"^q
} jN T+?2
public void run(){ GiS:Nq`$(
long now = System.currentTimeMillis(); C q)Cwc[H
if ((now - lastExecuteTime) > executeSep) { "xV0$%
//System.out.print("lastExecuteTime:"+lastExecuteTime); GvI8W)d3,R
//System.out.print(" now:"+now+"\n"); Nn='9s9F?}
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); S?<hs,
lastExecuteTime=now; fOJTy0jX8
executeUpdate(); v$~$_K
} #$ooV1E
else{ gnN"6r1
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); rBUWzpE"
} z=yE- I{
} O
8XHaVLg3
} *~0U4kw+
//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 7Xf52\7n
@RXkj-,eC#
类写好了,下面是在JSP中如下调用。 b!oj3|9
9|NH5A"H.
<% EFn[[<&><t
CountBean cb=new CountBean(); bZW dd6
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); |qz&d=>
CountCache.add(cb); {@ Z=b5/P
out.print(CountCache.list.size()+"<br>"); J>8kJCh9g
CountControl c=new CountControl(); 8e32NJ^k~
c.run(); X+kgx!u'y
out.print(CountCache.list.size()+"<br>"); 3*= _vl3
%>