The advantages of immutable objects in Java seem clear:
consistent state
automatic thread safety
simplicity
You can favour immutability by using private final fields and constructor injection.
But, what are the downsides to favouring immutable objects in Java?
i.e.
incompatibility with ORM or web presentation tools?
Inflexible design?
Implementation complexities?
Is it possible to design a large-scale system (deep object graph) that predominately uses immutable objects?
I have two variable TO_DATE and FROM_DATE. My table has two fields DOJ and DOL. I want to select all the records whose DOJ < TO_DATE and DOL FROM_DATE.
How can i write an SQL query in for this??
Say I have a struct:
struct MyStruct
{
public int X
public int Y
}
And a method in some class that is iterated over many times elsewhere:
public bool MyMethod( MyStruct myStruct )
{
return ...
}
Is changing the MyMethod signature to the following an acceptable optimization?
public bool MyMethod( ref MyStruct myStruct )
If so, how much of an advantage would it really be? If not, about how many fields would a struct need for a big enough advantage using ref this way?
I'm trying to add facebook connect button to my ZF web site. After i click on FB connect button the popup with email and password fields opens. But when i send email and password to login with facebook the popub don't close and reload the same page where the facebook connect button was.
Any idea?
Sorry for my english ..
Hi guys
Is there a way to check the data sent by a form to a PHP page return to the form page WITHOUT resetting the data sent and show a error?
The form has 20 fields and I need to check one of them on a bd. If it fails the user may be redirected to the form page with the form populated and displaying a error message on the field which is 'wrong'.
I would like any advice of a technique instead of populating each field using PHP.
I have "tasks" table with 3 fields:
date
priority (0,1,2)
done (0,1)
What I am trying to achieve is with the whole table sorted by done flag, tasks that are not done should be sorted by priority, while tasks that are done should be sorted by date:
Select * from tasks order by done asc
If done=0 additionally order by priority desc
If done=1 additionally order by date desc
Is it possible to do this in MySQL without unions?
Thanks.
Is there a way to specify a join on all fields from table A with only one field from table B?
Is it necessary to specify each individual field from each table instead of using the all symbol (*) for one of the tables?
Using logparser to import IIS logs to a db results in one column that has the date value and a second field for time:
2010-05-25 00:00:00.000 2010-01-01 11:11:58.000
I'd like to code an INSERT AFTER trigger that combines the 2 fields.
Hello folks,
Upon user interaction, I need to remove certain input params from an HTML form before submission. Using javascript to remove the input fields from the DOM doesn't seem to actually remove the params from being sent through the request.
Is there a way to delete or clear the actual request params?
I'm wanting to save some OpenId fields to a localdatabase table, such as
•Full Name
•openid url
•passworg
how to get those attributes from openid server?
please send me some example code in asp.net, c#...
Hello everyone,
I have a contact form and I added an image as a background. The background image is flickering when I move the mouse over the fields in IE(6,7,8).
If I remove the contact form (made with divs) everything is fine. I tried to build the form with table and I have the same problem.
Any solution?
Every idea is welcomed!
Thanks!
I'm not intimately familiar with CCK but I have a one-time custom setup and know that I could get some performance gains if I created indexes and changed the field type and length of some of the fields in my CCK table. Is it save to modify this table at all or will I end up destroying something in the process?
Thanks
my form is
class MapForm(forms.ModelForm):
class Meta:
model = Map
fields = ('mapName', 'kmlStr')
and the view is :
map_form = MapForm(request.POST or None)
if map_form.is_valid():
map = map_form.save(commit=False)
map.mapName=map_form.mapName#is thie code right ?
how to get the mapName 's value , us 'map_form.mapName' ?
thanks
I have 300 boolean fields in one table, and im trying to do somithing like that:
One string field:
10000010000100100100100100010001
Ha a simple way to do a simple search os this field like:
select * from table where field xor "10000010000100100100000000010001"
Im tring this but is to long:
select * from teste where mid(info,2,1) and mid(info,3,1)
:) Help!!
Hi:
I need help to do this query select.
for example I have these fields:
idInvoice
date
amount
Depending of the date I need multiply the field "amount" for x number or other one.
For example, if the date is less 01/01/2010 to multiply for 20 . But if it is major or equal to multiply for 35
Select idInvoice, date, amount, amount * varNumber from invoices
Hello, I have a web application. On the client side I basically need to get the values of some fields and turn them into JSON and then send them to the server in an AJAX kind of way.(asynchronous)
How would you do that? I also am using jQuery
I am on an oracle DB. Lets say I have one view that joins to three tables. The view has two fields each. Each field only needs data from two of the three tables.
If I query the view and return only one field, does the view still join to three tables or just to the two tables that it needs to calculate the field?
I'm new to Rails and am working with the collection_select method.
I have two fields I'd like to display in my select box:
first_name and last_name
So far, I can only display one or the other, not both.
Here's the code I'm working with:
collection_select(:hour,:shopper_id,@shoppers,:id,"last_name")
Thank you.
I have a Hashmap object that i am getting on a jsp page.
HashMap<Integer,Gift_product> gift_hm = new HashMap<Integer,Gift_product>();
gift_hm.put(17,new Gift_product("doll",67));
now i need to iterate this and display content on jsp.
as Gift_product class contains two fields name and price
jsp output should be
serial no. product name price
17 Doll 67
How can i achieve it..
I'm executing the following query
SELECT COUNT(*)
FROM table
WHERE field1='value' AND (field2 = 1000 OR field3 = 2000)
There is one index over field1 and another composited over field2&field3.
I see MySQL always selects the field1 index and then makes a join using the other two fields which is quite bad because it needs to join 146.000 rows.
Suggestions on how to improve this? Thanks
My question is easily summarized as: "Why does the following not work?"
teststruct = struct('a',3,'b',5,'c',9)
fields = fieldnames(teststruct)
for i=1:numel(fns)
fns(i)
teststruct.(fns(i))
end
output:
ans = 'a'
??? Argument to dynamic structure reference must evaluate to a valid field name.
Especially since teststruct.('a') does work. And fns(i) prints out ans = 'a'.
I can't get my head around it.
Need to integrate Django with an existing authentication system. That system has it's own database, API, login/logout,edit profile web pages and cookie.
(I may have to add a few additional profile fields stored/updated locally)
What's the proper approach to substitute the out-of-the-box authentication in Django?
I'm developing a standalone custom registry, custom login portlet, and custom profile portlet for Websphere Portal 6.1. Some existing users have not completed one or more required fields in their profiles.
The next time these users log in successfully, how can I get the portal to redirect them to the custom profile portlet before giving them access to the rest of the site?
Hello,
I 've got a table field (membername) which contains both the last name and the first name of users. Is it possible to split those into 2 fields (memberfirst - memberlast)? All the records have this format "Firstname Lastname" (without quotes and a space in between).