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: )Q.>rX,F
s D=n95`v
CountBean.java ( vca&wI!
9T1ZL5
/* Nd;Ku6
* CountData.java hC\6-
0u
* 49vcoHlf
* Created on 2007年1月1日, 下午4:44 <"_d]?,
* IyPwP*A
* To change this template, choose Tools | Options and locate the template under :AE&Ny4
* the Source Creation and Management node. Right-click the template and choose <>8WQn,K
* Open. You can then make changes to the template in the Source Editor. ` eXaT8
*/ 'nwx9]q
& 9<+;*/
package com.tot.count; w'm;82V:P-
/C6k+0ApMT
/** w'UVKpG+
* {QwHc5Bf
* @author PF53mUs4
*/ =W"F[fD
public class CountBean { +1D+]*t_?[
private String countType; 3nhXZOO1
int countId; R.yC(r
/** Creates a new instance of CountData */ i{`;R
public CountBean() {} fP.
6HF_p_
public void setCountType(String countTypes){ zR{W?_cV
this.countType=countTypes; aXoVy&x=
} jJ5W>Q1mK$
public void setCountId(int countIds){ [Lzw#XE
this.countId=countIds; oomT)gO 6*
} 4B^ZnFJ%m
public String getCountType(){ } x2DT8u
return countType; fc
|GArL#}
} @CT;g\4
public int getCountId(){ FGoy8+nB1M
return countId; 8/=L2fNN[
} dzDqZQY$
} z[3L2U~6
sL\L"rQN6
CountCache.java lhBT@5Dm9
fIsp;ca[k
/* #n#@fAY
* CountCache.java Y$?9Zkp>
* tQBRA/
* Created on 2007年1月1日, 下午5:01 "*Tb"
'O
* vuoQz\
* To change this template, choose Tools | Options and locate the template under hBBUw0"
* the Source Creation and Management node. Right-click the template and choose 6,0_)O}\b
* Open. You can then make changes to the template in the Source Editor.
K~| 4[\
*/ L{8xlx`
!y@6Mm
package com.tot.count; CW,Wx: Y
import java.util.*; l\@)y4
+
/** ::}{_ Z
* ;JayoJ
* @author FgB&b
*/ [m|YWT=
public class CountCache { .n~M(59
public static LinkedList list=new LinkedList(); Np"exFqN k
/** Creates a new instance of CountCache */ ~x]jB
public CountCache() {} 70eb]\%
public static void add(CountBean cb){ <c2'0I >
if(cb!=null){ Z\k&gio5C^
list.add(cb); \Hn>oonph
} lx[oaCr
} ,"HL~2:~
} Kq;8=xP[
z}MP)|aH:
CountControl.java /,g ,Ch<d
'coV^~qy
/* pLLGus+W
* CountThread.java t},/}b
* %>g3~yl
* Created on 2007年1月1日, 下午4:57 j4cwI90=
* 2(#7[mgPI
* To change this template, choose Tools | Options and locate the template under 0sfr d
* the Source Creation and Management node. Right-click the template and choose Yi$vg
* Open. You can then make changes to the template in the Source Editor. 61)-cVC
*/ *q-['"f
U
G~b a
package com.tot.count; }<9cL'
import tot.db.DBUtils; V;,{}
import java.sql.*; "gDb1h)8
/** AMyIAZnYq)
* v~@pMA$(h
* @author V{:A3C41
*/ TX&Jt%
public class CountControl{ xUa{1!Y8
private static long lastExecuteTime=0;//上次更新时间 YLiSbLz1
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 M!REygyx
/** Creates a new instance of CountThread */ F!]lU`z)=
public CountControl() {} =AEBeiz
public synchronized void executeUpdate(){
?B}{GL2)
Connection conn=null; wfq7ob4^
PreparedStatement ps=null; /#m=*&!CB
try{ H\0~#(z?.
conn = DBUtils.getConnection(); f7X6fr<
conn.setAutoCommit(false); E: $P=%b
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); ,#L=v]
for(int i=0;i<CountCache.list.size();i++){ -T[lx\}
CountBean cb=(CountBean)CountCache.list.getFirst(); [YUv7|\
CountCache.list.removeFirst(); J
/f
ps.setInt(1, cb.getCountId()); 0a-0Y&lQm
ps.executeUpdate();⑴ y"H*%]
//ps.addBatch();⑵ \uza=e
} t3&LO~Ye
//int [] counts = ps.executeBatch();⑶ $**r(HV
conn.commit(); Ljx(\Cm
}catch(Exception e){ d ysC4DS
e.printStackTrace(); &3TEfvz
} finally{ X ><?F|#7T
try{ +i@y@<l:+
if(ps!=null) { 4 Dw@r{
ps.clearParameters(); A*}.EClH
ps.close(); Dk(1}%0U/
ps=null; >JC
} s#)5h0t#du
}catch(SQLException e){} ^]W<X"H+Z
DBUtils.closeConnection(conn); {6_|/KE9_
} --|Wh^i>?
} Zw ^kmSL"
public long getLast(){ !AKg m'Nw
return lastExecuteTime; oaoU _V
} / ;,Md,p
public void run(){ @AIaC-,~]
long now = System.currentTimeMillis(); M>i9 i-dU
if ((now - lastExecuteTime) > executeSep) { >76\nGO
//System.out.print("lastExecuteTime:"+lastExecuteTime); \4-"L>
//System.out.print(" now:"+now+"\n"); OeS\7
// System.out.print(" sep="+(now - lastExecuteTime)+"\n");
ng_^
lastExecuteTime=now; o!{w"K
executeUpdate(); 2M68CE
} 7]||UuF<
else{ o'f?YZ$.
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); {:]9Q Tq
} e= .njMqW5
} LRb{hUt=
} TiO"xMX
//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 jN6uT&{T
~==>pj
类写好了,下面是在JSP中如下调用。 FMClSeO7
p4-o/8rO
<% uoX:^'q
CountBean cb=new CountBean(); \8?Tdx=
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); * Of4o
CountCache.add(cb); Z`KC%!8K
out.print(CountCache.list.size()+"<br>"); Nz],IG.
CountControl c=new CountControl(); f-E("o
c.run(); t 0|!(3
out.print(CountCache.list.size()+"<br>"); 5[YDZ7g"~
%>