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: vJ
+sdG
.Iu8bN(L`
CountBean.java ^l,(~03_
VL =1 9[
/* T<o^f
n,H
* CountData.java EWb'#+BP
* k<&zVV'
* Created on 2007年1月1日, 下午4:44 XY_hTHJ
* dmR>u
* To change this template, choose Tools | Options and locate the template under %yyvB5Y^
* the Source Creation and Management node. Right-click the template and choose RZY[DoF8u
* Open. You can then make changes to the template in the Source Editor. s0zN#'o]
*/ E{wnhsl{
!g`^<y!
package com.tot.count; 54lU~ "
[TW?sW^0
/** GgU8f0I
* s'7PHP)LOJ
* @author xM+_rU
M|h
*/ {/)q=
public class CountBean { $a@T:zfe
private String countType; v3*y43
int countId; nE&`~
/** Creates a new instance of CountData */ i]cD{hv
public CountBean() {} 4Eri]O Ri
public void setCountType(String countTypes){ ^
gMkQYo(#
this.countType=countTypes; I>bO<T`
} qsT@aSIo9
public void setCountId(int countIds){ /VmtQ{KTt+
this.countId=countIds; ~cf*Oq
} o^efeI
public String getCountType(){ $q|-9B
return countType; t6,bA1*5y
} 8mm]>u$
public int getCountId(){ wB(X(nr
return countId; **G5fS.^W
} ]Pp}=hcD
} p{vGc-zP.
/!i`K{
CountCache.java YAdk3y~pL
CyV2=o!F w
/* JhU"akoK
* CountCache.java /Kd9UQU
* i8h^~d2"
* Created on 2007年1月1日, 下午5:01 [yhK4A
* 1PN!1= F}
* To change this template, choose Tools | Options and locate the template under 3|0wD:Dy
* the Source Creation and Management node. Right-click the template and choose ` ;}w!U
* Open. You can then make changes to the template in the Source Editor. d :vuRK4+
*/ S{Q2KD
7WMF8(j5
package com.tot.count; nb~592u
import java.util.*; "-
?uB Mz
/** n1Wo<$#
* v[2N-
* @author +^ cjdH*
*/ j[RY
public class CountCache { h(/& ;\Cr
public static LinkedList list=new LinkedList(); ^$AJV%3wI
/** Creates a new instance of CountCache */ %TeH#%[g>\
public CountCache() {} &v/>P1Z
G
public static void add(CountBean cb){ KU=+ 1,Jf
if(cb!=null){ 9_b_O T
list.add(cb); iAr]Ed"9|
} yno X=#`
} xxQgX~'x
} V<i_YLYmJe
K%g_e*"$
CountControl.java |
9 <+!t\
1KadT7<0}
/* *%ta5a
* CountThread.java t ch;_7?
* iBt<EM]U/
* Created on 2007年1月1日, 下午4:57 ]~@uStHn
* 7PW7&]-WQ
* To change this template, choose Tools | Options and locate the template under RxA:>yOPn
* the Source Creation and Management node. Right-click the template and choose v&)G~cz
* Open. You can then make changes to the template in the Source Editor. 0t?g!
*/ re xMS
A7I{Le
package com.tot.count; ;U&~tpd
import tot.db.DBUtils; d6f T
import java.sql.*; UlMc8 z
/** ]^0mh["
* ANRZQpnXQ
* @author s}<i[hY>
*/ |vPU]R>6
public class CountControl{
WjsmLb:5
private static long lastExecuteTime=0;//上次更新时间 M#.dF{%%
private static long executeSep=60000;//定义更新间隔时间,单位毫秒 Ms=N+e$n
/** Creates a new instance of CountThread */ $YiG0GK<"
public CountControl() {} %%T?LRv
public synchronized void executeUpdate(){ C*stj
Connection conn=null; ^Z+p_;J$p
PreparedStatement ps=null; w
y&yK*w
try{ GOUO
conn = DBUtils.getConnection(); "!R*f $
conn.setAutoCommit(false); aQj"FUL
ps=conn.prepareStatement("update t_news set hits=hits+1 where id=?"); pHzl/b8
for(int i=0;i<CountCache.list.size();i++){ v[\GhVb
CountBean cb=(CountBean)CountCache.list.getFirst(); = G>Y9Sc
CountCache.list.removeFirst(); +,zV
[\
ps.setInt(1, cb.getCountId());
tRbZX{
ps.executeUpdate();⑴ 2t;3_C
//ps.addBatch();⑵ qV)hCc/ ~
} i.0d>G><@
//int [] counts = ps.executeBatch();⑶ @ek8t2??x
conn.commit();
+O4//FC-"
}catch(Exception e){ wWVB'MRXB,
e.printStackTrace(); tkP& =$
} finally{ [
e#[j{
try{ )S9}uOG#
if(ps!=null) { `4,]Mr1b
ps.clearParameters(); zgl$ n
ps.close(); $wcTUl
ps=null; *>k6n5%
} ui80}%
}catch(SQLException e){} JYnyo$m/
DBUtils.closeConnection(conn); wAo6:)
} -XfGF<}r
} MM*9Q`cB
public long getLast(){ $+ORq3
return lastExecuteTime; ? CU;
} g:YUuZ
public void run(){ H<"EE15
long now = System.currentTimeMillis(); YbF}>1/"
if ((now - lastExecuteTime) > executeSep) { z+c'-!e/
//System.out.print("lastExecuteTime:"+lastExecuteTime); 7#j9"*
//System.out.print(" now:"+now+"\n"); XEUS)X)
// System.out.print(" sep="+(now - lastExecuteTime)+"\n"); qga\icQr
lastExecuteTime=now; rAk;8)O$
executeUpdate(); Rl'xEtaN
} xLP8*lvy
else{ 24*3m&fA*K
//System.out.print("wait for "+(now - lastExecuteTime)+" seconds:"+"\n"); t$PJ*F67M
} (ZP e{;L.
} 1U(!%},
} cR/e
Zfl
//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 @9lGU#
*,
R ~[g
类写好了,下面是在JSP中如下调用。 L+Gi
uT
Y G/O
<% A:\_ \B%<
CountBean cb=new CountBean(); 0zk054F'
cb.setCountId(Integer.parseInt(request.getParameter("cid"))); H'I5LYsXO~
CountCache.add(cb); hVdGxT]6
out.print(CountCache.list.size()+"<br>"); ?lm<)y?I7+
CountControl c=new CountControl(); CVZ4:p
c.run(); 7
6HB@'xY
out.print(CountCache.list.size()+"<br>"); c^R "g)gr
%>