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Can overridden methods differ in return type?
...pe is assignable to the return type of the method you are overriding, it's allowed.
For example:
class ShapeBuilder {
...
public Shape build() {
....
}
class CircleBuilder extends ShapeBuilder{
...
@Override
public Circle build() {
....
}
This is specified in section...
MySQL: Large VARCHAR vs. TEXT?
...ords messages between users. Apart from the typical ids and message types (all integer types) I need to save the actual message text as either VARCHAR or TEXT. I'm setting a front-end limit of 3000 characters which means the messages would never be inserted into the db as longer than this.
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Retrieving the COM class factory for component with CLSID {XXXX} failed due to the following error:
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You deserve more than a +1 but +1 is all I have to give
– David
Dec 5 '13 at 14:59
8
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MySQL INNER JOIN select only one row from second table
...ltiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
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How can one pull the (private) data of one's own Android app?
...Android 4.4.2) Which is the same effect as when the manifest shows android:allowBackup="false"
– Someone Somewhere
Jun 5 '14 at 0:27
2
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How do I resolve “HTTP Error 500.19 - Internal Server Error” on IIS7.0 [closed]
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In my web.config there was a URL rewrite module rule and I haven’t installed URL rewrite module also. After I install url rewrite module this problem solved.
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What are the differences between ipython and bpython?
...g.
Run functions in the background in a separate task with %bg.
A whole parallel programming environment (not really a feature you expect from an interactive Python shell, but IPython offers it).
This list could be nearly arbitrarily continued. And of course there will be lots of features in bpyt...
Mongo: find items that don't have a certain field
...rpret it as the field has to be equal to null and not missing. This is actually unexpected behavior, because you wouldn't be able to do the same for 0 (which is also false), so null is kind of the exception here. Therefore, best practice is the more readable answer using $exists: false which is not ...
WPF: Grid with column/row margin/padding?
...d in grid with a style declaration. Takes care of adding padding/margin to all elements without having to define for each, which is cumbersome and labor-intensive.For instance, if your Grid contains nothing but TextBlocks, you can do this:
<Style TargetType="{x:Type TextBlock}">
<Sette...
How do I convert a string to a number in PHP?
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You don't typically need to do this, since PHP will coerce the type for you in most circumstances. For situations where you do want to explicitly convert the type, cast it:
$num = "3.14";
$int = (int)$num;
$float = (float)$num;
...