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: bicbCC6kC
/RWD\u<l
CountBean.java I[n|#N
#wsi><7
/* ~^fb`f+%
* CountData.java D/wJF[_
* VKSn \HT~
* Created on 2007年1月1日, 下午4:44 G[{Av5g mx
* vTC{
* To change this template, choose Tools | Options and locate the template under }-Jo9dNs
* the Source Creation and Management node. Right-click the template and choose =o'g5Be<F
* Open. You can then make changes to the template in the Source Editor. b)r;a5"<5
*/ lWBewnLKE
C(M ?$s`
package com.tot.count; 4P#4RB
3jHE,5m
/** 7W>(T8K X\
* Qm_;o(
* @author }#&L
*/ g@Rs.Zq
public class CountBean { 7JBr{3;eS
private String countType; {e0(M*u
int countId; z|zEsDh;
/** Creates a new instance of CountData */ :`uu[^
public CountBean() {} HmHM#~5(`
public void setCountType(String countTypes){ F6"s&3D{
this.countType=countTypes; I6,||!sZ
} L XTtV0F
public void setCountId(int countIds){ B[t>T>~
this.countId=countIds; #+$PD`j
} LZQG.
public String getCountType(){ ?A-f_0<0
return countType; ScmwHid:\
} [&(~1C|C
public int getCountId(){ m[BpV.s
return countId; ~g;)8X;;+
} 1-Dw-./N
} r~2q`l'>
{Q@?CT
CountCache.java 8/;@4^Ux
hBhbcWD,ka
/* *w}r:04F
* CountCache.java G"".;}AV
* j3u!lZ}U
* Created on 2007年1月1日, 下午5:01 t3=K>Y@w
* NLUiNfCR
* To change this template, choose Tools | Options and locate the template under _joW%`T8
* the Source Creation and Management node. Right-click the template and choose Y=y
0`?K
* Open. You can then make changes to the template in the Source Editor. .:e#!~Ki
*/ p(9[*0.};
qggRS)a
package com.tot.count; IYa(B+nB)
import java.util.*; e*d lGK3l
/** dJlK'zK
* U8@P/Z9
* @author p&D7&Sb[
*/ x6^FpNgQ
public class CountCache { 9#kk5 )J
public static LinkedList list=new LinkedList(); s4 Vju/
/** Creates a new instance of CountCache */ ,fo7.
h4{
public CountCache() {} uO1^nK
public static void add(CountBean cb){ 7p>T6jK)
if(cb!=null){ A$L:,b(
list.add(cb); bfkFk
} RJ{J~-q{
} yV31OBC:
}
GB,ub*|
ID,os_ T=
CountControl.java rje;Bf
lA`-"
/* dTte4lh
* CountThread.java =5uhIU0O
* z)Yb9y>2
* Created on 2007年1月1日, 下午4:57 yh).1Q-D
* U!YoZ?
* To change this template, choose Tools | Options and locate the template under ngk:q5Tp
* the Source Creation and Management node. Right-click the template and choose ^ (J%)&_\3
* Open. You can then make changes to the template in the Source Editor. Nz%pl!
*/ j HObWUX
B[2t.d;h
package com.tot.count; N
x^JC_
import tot.db.DBUtils; l_,6<wWp
import java.sql.*; Mgu9m8
`J
/** xn)F(P 0kv
* }iLi5Qkx
* @author \g v-2.,
*/ NGZtlNvh
public class CountControl{ Bx.hFEL
private static long lastExecuteTime=0;//上次更新时间 "#iO{uMWb
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 TJB4N$-}A
/** Creates a new instance of CountThread */ e-.(O8
public CountControl() {} 1f?Fuw
public synchronized void executeUpdate(){ 8cRc5X
Connection conn=null; 9Vt6);cA-]
PreparedStatement ps=null; A;f)`i0l,
try{ %CgmZTz~<
conn = DBUtils.getConnection(); p:ZQ*Ue
conn.setAutoCommit(false); -^8OjGat
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); Y^|15ek
for(int i=0;i<CountCache.list.size();i++){ [g{fz3
O6
CountBean cb=(CountBean)CountCache.list.getFirst(); L3j
~O oo
CountCache.list.removeFirst(); S(rnVsW%Ki
ps.setInt(1, cb.getCountId()); B}aW y &D
ps.executeUpdate();⑴ T8x /&g''
//ps.addBatch();⑵ 0rif,{"
} >:0N)Pj
//int [] counts = ps.executeBatch();⑶ 9_Z_5w;h
conn.commit(); #W8c)gkG9
}catch(Exception e){ YF %]%^n
e.printStackTrace(); f/Z-dM\e
} finally{ rxZk!- t)L
try{ %:dd#';g
if(ps!=null) { VP7LKfv
ps.clearParameters(); >!c Ff$2'
ps.close(); PE[5oH
ps=null; _ -,[U{
} e$mVA}>Ybp
}catch(SQLException e){} MR,A{X
DBUtils.closeConnection(conn); YeB C6`7y
} `}8)P#
} '%YTMN@
public long getLast(){ `];ne]xM
return lastExecuteTime; Ad-_=a%
} !L_xcov!Y
public void run(){ [G[{?{
long now = System.currentTimeMillis(); BL%&n*&
if ((now - lastExecuteTime) > executeSep) { TaKCN
//System.out.print("lastExecuteTime:"+lastExecuteTime); "`'+@KlE
//System.out.print(" now:"+now+"\n"); .RS
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); [T,Df&
lastExecuteTime=now; DYew6B-
executeUpdate(); 9N|JI3*41
} 9yLPh/!Ob
else{ ?pA_/wwp
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); B E#pHg
} "#{b)!EH
} 3;!a'[W&p
} /N@NT/.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 SO~pe$c-
Yt r*"-
类写好了,下面是在JSP中如下调用。 H
'nLC,
9mpQusM
<% [yRqSB
CountBean cb=new CountBean(); [y<s]C6E
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); <FN+
CountCache.add(cb); ](IOn:MuDE
out.print(CountCache.list.size()+"<br>"); h^J :k
CountControl c=new CountControl(); Exat_ L'?
c.run(); dE(d'*+a
out.print(CountCache.list.size()+"<br>"); p%OVl[^jp
%>