What is the best practice in this case?

I want to create a vending machine simulation program.
The design will be something like this :
GUI----use----VendingMachine----has----ProductStorage
Previously, i want everything inside VendingMachine will be transparent from the GUI.
The GUI just use VendingMachine, and it has no knowledge about ProductStorage.
But then i realize that in order for the GUI to display the products, it has to use ProductStorage.
So i came up with adding this getter to VendingMachine class :
public ProductStorage getStorage()
return storage;
}I'm breaking the rules of encapsulation.
Is it okay to do this? What is the practice in this case?
Thanks,
Ang.

GUI----use----VendingMachine----has----ProductStorage
Previously, i want everything inside VendingMachine will be transparent from the GUI.
The GUI just use VendingMachine, and it has no knowledge about ProductStorage.
But then i realize that in order for the GUI to display the products, it has to use ProductStorage.Not necessarily. You can expose the ProductStorage interface (did I get this right: methods such as getProductList(), getProductQuantity(String productId) ?), in VendingMachineImpl. That latter can simply delegates to its ProductStorage collaborator. The GUI code doesn't need to know this latter is a separate instance.
I'm breaking the rules of encapsulation.
Is it okay to do this? What is the practice in this case?Technically you're violating the so-called Law of Demeter, which as you mention means you reveal implementation details to the client - and makes it less flexible, if you ever want to move ProductStorage API in another class. For example it would exhibit transaction logic to the client code.
OK we're talking about a far-fetched exemple, part of an exercise, but in general you should avoid this.

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WhatÃÂ¢ÃÂÃÂs the best practice for this scenario?

Hi,
My users want the ability to change the WHERE and/or ORDER BY clause at runtime. They may define user preferences on each screen ( which is bind to a view object). They want to see the same records based on WHERE/ORDER BY defined on the last visit. That is why I keep the users preferences and load the screen based on that, using :
View.setWhereClause(...);
View.setOrderByClause(...);
View.executeQuery();
This works good when only one user working with the application but faced low performance when more than one user working with the application.
What are the points to increase the performance and what is the best practice for this scenario?
Thanks for your help in advance.

Sung,
I am talking only about 2 users in my testing. I am sure i missed something but could not recognize that.
This page is my custom query page including a tag to instantiate app module in stateful mode at the top <jbo:ApplicationModule..> and a tag to instantiate data source <jbo:Datasource...> and release tag at the bottom <jbo:ReleasePageResources..> and some java code in the middle(body). The java code constructed the query statement and then fires the query to set the view object based on the query statement using the above methods.
So, I am facing very slow performance(speed) when two clients load this page at the same time. Looks like the entire application locks for others when one client load this page and fire the query. i realized the battle neck is where executeQuery() is executing.
what do you think.
Thanks in advance for your comments.

What is the best practice for this?

Hi,
I have a huge package, let's say including 100 procedures.
These procedures(with package name qualifier) are called all around the application. Now i want to divide it to 5 packages each one including 20 procedures.
What is the best practice to do this with minimum changes in the application?

First step before doing anything with OD is to make certain that local DNS services are correct. To verify that, launch Terminal.app from Applications > Utilities on the test server, and issue the following harmless, diagnostic command:
sudo changeip -checkhostname
You'll need to enter your administrative password for the sudo to be accepted.
If the output from that command reports no changes are required, then an export from the original OD and an import into the test system would be typical for testing, if you trust what's in the original OD.

Coalesce or compress this index? what is the best solution in this case?

BANNER
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64biI have executed the following query on a specific index that I suspected to be smashed and got the following result
select
    keys_per_leaf, count(*) blocks
from (
      select   sys_op_lbid (154813, 'L', jus.rowid) block_id,
             count (*)                            keys_per_leaf
      from xxx_table jus
       where jus.id is not null
              or jus.dat is not null
      group by sys_op_lbid (154813, 'L', jus.rowid)
group by keys_per_leaf
order by keys_per_leaf;
keys_per_leaf     blocks
1     80
2     1108
3     2816
4     3444
5     3512
6     2891
7     2579
8     2154
9     1943
10     1287
11     1222
12     1011
13     822
14     711
15     544
16     508
17     414
18     455
19     425
20     417
21     338
22     337
23     327
24     288
25     267
26     295
27     281
28     266
29     249
30     255
31     237
32     259
33     257
34     232
35     211
36     209
37     204
38     216
39     189
40     194
41     187
42     200
43     183
44     167
45     186
46     179
47     179
48     179
49     171
50     164
51     174
52     157
53     181
54     192
55     178
56     162
57     155
58     160
59     153
60     151
61     133
62     177
63     156
64     167
65     162
66     171
67     154
68     162
69     163
70     153
71     189
72     166
73     164
74     142
75     177
76     148
77     161
78     164
79     133
80     158
81     176
82     189
83     347
84     369
85     239
86     239
87     224
88     227
89     214
90     190
91     230
92     229
93     377
94     276
95     196
96     218
97     217
98     227
99     230
100     251
101     266
102     298
103     276
104     288
105     638
106     1134
107     1152
229     1
230     1      This is a 5 columns unique key index on (id number, dat date, id2 number, dat2 date type number).
Furthermore, a space analysis of this index using dbms_space.space_usage gives the following picture
Number of blocks with at least 0 to 25% free space            = 0                   -------> total bytes = 0
Number of blocks with at least 25-50% free space              = 75                 -------> total bytes = ,5859375
Number of Blocks with with at least 50 to 75% free space = 0                   -------> Total Bytes = 0
number of blocks with at least 75 to 100% free space        = 0                   -------> total bytes = 0
Number of full blocks with no free space                              = 99848           -------> total bytes = 780,0625
Total blocks ______________________________
99923
Total size MB______________________________
799,384It seems for me that this index needs to be either coalesced or compressed.
Then, what would be the best option in your opinion?
Thanks in advance
Mohamed Houri
Edited by: Mohamed Houri on 12-janv.-2011 1:18

So let me continue my case
I first compressed the index as follows
alter index my_index rebuild compress 2;which immediately presents two new situations
(a) index space
Number of blocks with at least 0 to 25% free space    = 0                -------> total bytes = 0
Number of blocks with at least 25-50% free space      = 40              -------> total bytes =, 3125
Number of Blocks with at least 50 to 75% free space   = 0                -------> total Bytes = 0
Number of blocks with at least 75 to 100% free space = 0                -------> total bytes = 0
Number of full blocks with no free space                = 32361           -------> total bytes = 252, 8203125
Total blocks ______________________________
32401
Total size Mb______________________________
259,208meaning that the compress command freed up 67487 leaf blocks and reduced the size of the index from to 799,384 MB to 259,208 MB.
It also shows a relative nice pictue of number of keys per leaf block (when compared to the previous situation)
(b) on the number of key per leaf block
KEYS_PER_LEAF     BLOCKS
4     1
6     1
13     1
15     1
25     1
62     1
63     1
88     1
97     1
122     1
123     3
124     6
125     4
126     2
289     4489
290     3887
291     3129
292     2273
293     1528
294     913
295     442
296     152
297     50
298     7
299     1      In a second step, I have coalesced the index as follows
alter index my_index coalesce;which produces the new figure
Number of blocks with at least 0 to 25% free space     = 0          -------> total bytes = 0
Number of blocks with at least 25-50% free space      = 298        -------> total bytes = 2,328125
Number of Blocks with at least 50 to 75% free space   = 0           -------> Total Bytes = 0
Number of blocks with at least 75 to 100% free space = 0            -------> total bytes = 0
Number of full blocks with no free space = 32375                    -------> total bytes = 252, 9296875
Total blocks ______________________________
32673
Total size MB______________________________
261,384meaning the the coalesce command has made
(a)     298-40 = 258 new blocks with 25-50% of free space
(b)     32375-32361 = 14 new additional blocks which have been made full
(c)     The size of the index increased by 2,176MB (261,384-259,208)
While the number of key per leaf block keeps in the same situation
KEYS_PER_LEAF     BLOCKS
4     2
5     3
9     1
10     2
12     1
13     1
19     1
31     1
37     1
61     1
63     1
73     1
85     1
88     1
122     1
123     4
124     4
125     3
126     1
289     4492
290     3887
291     3125
292     2273
293     1525
294     913
295     441
296     152
297     50
298     7
299     1      Could you please through some light on the difference between the compress and the coalesce on the effect they have made on
(a) the number of keys per leaf blocks within my index
(b) the space and size of my index?
Best regards
Mohamed Houri

When displaying just One WDiView in the Portal what is the best practice?

Hi,
I´m configuring some Roles to display WebDynpro iViews and I´m concerned because when a page has to display just one iView I don´t create the Page but instead I call the iView directly into the Role and the Displayed iView is viewed correctly, my concern began cause I´m checking SAP standard roles, WDiviews and WDPages and eventhough there is just one WDiView to be displayed a WDPage is been created to display it and the WD page id assigned to the Role.
Does anyone knows what is the best practice in this case?
Thanx in Advanced and Kind Regards,
Gerardo J

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Appl. Hierarchy and Package Hierarchy - what is the Best practice ?

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From ABAP Workbench select Overview->Applic. hierarchy->SAP or Customer
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What is the best practice for changing view states?

I have a component with two Pie Charts that display
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I would stick with non-states, as I have always heard that
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What is the best practice for full browser video to achieve the highest quality?

I'd like to get your thoughts on the best way to deliver full-browser (scale to the size of the browser window) video. I'm skilled in the creation of the content but learning to make the most out of Flash CS5 and would love to hear what you would suggest.
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import flash.net.URLRequest;
import flash.display.Bitmap;
import flash.display.BitmapData;
import flash.ui.Mouse;
import flash.events.Event;
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What is the best practice for voicemail migration?

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Regards,
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Hi Alex,
I was seeing the DOC which says that
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http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/unity_exp/rel7_1/Licensing/CUELicensing_book/csa_overview_CUE.html#wp1101175
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regds,
aman

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What are the best practices to connect 30-40 iPads to Wi-Fi in a single room?

I don't use it but it does say this in the help section...

What are the best practices to migrate VPN users for Inter forest mgration?

What are the best practices to migrate VPN users for Inter forest mgration?

It depends on a various factors. There is no "generic" solution or best practice recommendation. Which migration tool are you planning to use?
Quest (QMM) has a VPN migration solution/tool.
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Santhosh Sivarajan | Houston, TX | www.sivarajan.com
ITIL,MCITP,MCTS,MCSE (W2K3/W2K/NT4),MCSA(W2K3/W2K/MSG),Network+,CCNA
Windows Server 2012 Book - Migrating from 2008 to Windows Server 2012
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Twitter: Twitter
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Microsoft Virtual Academy
This posting is provided AS IS with no warranties, and confers no rights.

What is the best practice in securing deployed source files

hi guys,
Just yesterday, I developed a simple image cropper using ajax
and flash. After compiling the package, I notice the
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"What is the best practice in securing deployed source
files?"
How do we secure application installed source files from
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source files after it's been installed. E.g. modifying spraydata.js
files for example can be done easily with an editor.

Hi,
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of daily capture and final data tables on these two key columns. Then I delete the rows in the daily capture table which match the #temp table. Then I insert the remaining rows from daily capture into the final data table.
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What is the best practice for inserting unique (new) rows and ignoring duplicate rows (rows that already exist in both the daily capture and final data tables) in my particular operation?
Rich P

Please follow basic Netiquette and post the DDL we need to answer this. Follow industry and ANSI/ISO standards in your data. You should follow ISO-11179 rules for naming data elements. You should follow ISO-8601 rules for displaying temporal data. We need
to know the data types, keys and constraints on the table. Avoid dialect in favor of ANSI/ISO Standard SQL. And you need to read and download the PDF for:
https://www.simple-talk.com/books/sql-books/119-sql-code-smells/
>> My final data table contains a two key columns unique key constraint. [unh? one two-column key or two one column keys? Sure wish you posted DDL] I insert data into this table from a daily capture table (which also contains the two columns that make
up the key in the final data table but are not constrained (not unique) in the daily capture table). <<
Then the "capture table" is not a table at all! Remember the fist day of your RDBMS class? A table has to have a key. You need to fix this error. What ETL tool do you use?
>> I don't want to insert rows from daily capture which already exists in final data table (based on the two key columns). <<
MERGE statement; Google it. And do not use temp tables.
--CELKO-- Books in Celko Series for Morgan-Kaufmann Publishing: Analytics and OLAP in SQL / Data and Databases: Concepts in Practice Data / Measurements and Standards in SQL SQL for Smarties / SQL Programming Style / SQL Puzzles and Answers / Thinking
in Sets / Trees and Hierarchies in SQL

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What is the Best practice for ceramic industry?

Dear All;
i would like to ask two questions:
1- which manufacturing category (process or discrete) fit ceramic industry?
2- what is the Best practice for ceramic industry?
please note from the below link
[https://websmp103.sap-ag.de/~form/sapnet?_FRAME=CONTAINER&_OBJECT=011000358700000409682008E ]
i recognized that ceramic industry is under category called building material which in turn under mill product and mining
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thanks in advance

Hi,
I understand that you refer to production of ceramic tiles. The solution for PP was process, with these setps: raw materials preparation (glazes and frits), dry pressing (I don't know extrusion process), glazing, firing (single fire), sorting and packing. In Spain, usually are All-in-one solutions (R/3 o ECC solutions). Perhaps the production of decors have fast firing and additional processes.
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Eduardo

What is the best practice in this case?

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