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: #A~7rH%hi
nx!+:P ,
CountBean.java >+%0|6VSb
H@|m^1
/* Kciz^)'Z
* CountData.java IR8qFWDZ
* $GD
Q1&Z
* Created on 2007年1月1日, 下午4:44 u`*1OqU
* 0\1g-kc!v
* To change this template, choose Tools | Options and locate the template under S""F58H n
* the Source Creation and Management node. Right-click the template and choose bhKe"#m|S
* Open. You can then make changes to the template in the Source Editor. wEl/s P
*/ B?d+^sz]
;Yt'$D*CP
package com.tot.count; WuQ;Da0+_F
C)cuy7<
/** QwnqysNx4
* <.
V*]g/;
* @author +^$E)Ol
*/ 0|mCk
public class CountBean { Q^'xVS_.
private String countType; "Qk)EY
int countId; \mFgjPz
/** Creates a new instance of CountData */ ZQsVSz( 1
public CountBean() {} G,b*Qn5#
public void setCountType(String countTypes){ k4JTc2b
this.countType=countTypes; @n$/2y_.
} dp }zG+
public void setCountId(int countIds){ (Wn^~-`=+
this.countId=countIds; Go7 oj'"
} DLoH.Fd
public String getCountType(){ Dd:48sN:Jq
return countType; FD8d-G
} =]L ALw
public int getCountId(){ ZkF6AF
return countId; > q8)~
} :f0#4'f
} mfk^t`w_
pvdCiYo1r
CountCache.java g7v(g?
`>HrO}x^
/* H6MG5f_
* CountCache.java p|w0
i[hc
* ($,qxPOn
* Created on 2007年1月1日, 下午5:01 YN7JJJ/~T
* Eo0/cln|
* To change this template, choose Tools | Options and locate the template under O0sLcuT$
* the Source Creation and Management node. Right-click the template and choose j;EH[3
* Open. You can then make changes to the template in the Source Editor. HDj260a
*/ Pk`3sfz
UYhxgPGsj
package com.tot.count;
=tc!"{
import java.util.*; 2CV? cm
/** 2k^'}7G%
* D/Py?<n-B
* @author `ix&j8E22w
*/ ,k}(]{ -
public class CountCache { aqv'c
j>
public static LinkedList list=new LinkedList(); [=^Wj`;
/** Creates a new instance of CountCache */ Yb%#\.M/y
public CountCache() {} vU9:`@beu
public static void add(CountBean cb){ L fZF
if(cb!=null){ f7&9IW`7F^
list.add(cb); U.N?cKv
} ">vi=Tr
} HmbQL2
} FzG>iC}
<4582x,G
CountControl.java wv^n#
gzN51B =D
/* ]#vi/6\J
* CountThread.java Qw<&N$
* gKtgW&PYm
* Created on 2007年1月1日, 下午4:57 @]Lu"h#u=
* }ldpudU
* To change this template, choose Tools | Options and locate the template under 664D5f#EJ
* the Source Creation and Management node. Right-click the template and choose Pk;YM}
* Open. You can then make changes to the template in the Source Editor. \jx3Fs:Q
*/ ,(NN)Oj
h=B=
J
package com.tot.count; >~_)2_j
import tot.db.DBUtils; -B?cF9
import java.sql.*; aP#/%
/** Q"H/RMo-
* I:("f+
H
* @author z, n[}Q#u
*/ 5<YL^m{/L
public class CountControl{ tTWEhHQ`
private static long lastExecuteTime=0;//上次更新时间 'UM *7
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 !@ {sM6U
/** Creates a new instance of CountThread */ -F MonM
public CountControl() {} fg4mP_
public synchronized void executeUpdate(){ U*?`tdXJ$
Connection conn=null; V)P8w#,
PreparedStatement ps=null; <>)N$$Rx&
try{ uaZHM@D
conn = DBUtils.getConnection(); }b/P\1#z
conn.setAutoCommit(false); L@Q+HN
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); AWJA?
for(int i=0;i<CountCache.list.size();i++){ ]J@-,FFC
CountBean cb=(CountBean)CountCache.list.getFirst(); tS-gaT`T
CountCache.list.removeFirst(); !s:e
ps.setInt(1, cb.getCountId()); -gUp/#l1
ps.executeUpdate();⑴ buT6)~lw
//ps.addBatch();⑵ b`@J"E}
} iu3L9UfL[
//int [] counts = ps.executeBatch();⑶ T"<)B^8f
conn.commit(); 'by+hXk
}catch(Exception e){ jcb&h@T8kv
e.printStackTrace(); W1EYVXN
} finally{ N1B$z3E*
try{ 9Vo*AK'&U
if(ps!=null) { Keem\/
ps.clearParameters(); ZJ.an%4
ps.close(); SMzq,?-`
ps=null; n2EPx(~
} <'N:K@Cs
}catch(SQLException e){} *ifz@8C }
DBUtils.closeConnection(conn); 5{Q9n{dOh
}
I Zw
} :q?#$?
public long getLast(){ FRQ0t!b<M1
return lastExecuteTime; 3&nN;4~Zx6
} 9bspf {
public void run(){ :
]+6l
long now = System.currentTimeMillis(); cnI5G!
if ((now - lastExecuteTime) > executeSep) { 5n{d jP
//System.out.print("lastExecuteTime:"+lastExecuteTime); AI`k
}sA~
//System.out.print(" now:"+now+"\n"); Ri~$hs!
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); H2+b3y-1a]
lastExecuteTime=now; L9lJ4s
executeUpdate(); 5OzEY7K)
} !&9(D^
else{ gKQV99
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); W"GW[~
h
} eLnS1w2
} Qd{8.lB~LQ
} qR_>41JU"
//注:如果你的数据库驱动支持批处理,那么可以将⑵,⑶标记的代码前的注释去掉,同时在代码⑴前加上注释 ^'a#FbMtt
bwH[rT!n
类写好了,下面是在JSP中如下调用。 ~$J(it-a
~UZ3 lN\E
<% a[ayr$Hk?
CountBean cb=new CountBean(); ^
nI2<P
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); "r*`*1
CountCache.add(cb); Q;g7<w17
out.print(CountCache.list.size()+"<br>"); IWq#W(yM
CountControl c=new CountControl(); &N._}ts
c.run(); ,G g;:)k\
out.print(CountCache.list.size()+"<br>"); EK Vcz'w
%>