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Do Java arrays have a maximum size?
...ry easy to test.
In a recent HotSpot VM, the correct answer is Integer.MAX_VALUE - 5. Once you go beyond that:
public class Foo {
public static void main(String[] args) {
Object[] array = new Object[Integer.MAX_VALUE - 4];
}
}
You get:
Exception in thread "main" java.lang.OutOfMemoryEr...
PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
...
Usage of __slots__?
What is the purpose of __slots__ in Python — especially with respect to when I would want to use it, and when not?
11 A...
Should I use a class or dictionary?
...ould your __init__ code go?
Classes are for bundling related data (and usually code).
Dictionaries are for storing key-value relationships, where usually the keys are all of the same type, and all the values are also of one type. Occasionally they can be useful for bundling data when the key/attri...
How to enumerate an object's properties in Python?
...oes not return dynamic members (i.e., object attributes and methods dynamically defined by that object's __getattr__() method or similar magic). In all likelihood, your desired file.ImplementationName property is defined dynamically and hence not available to vars() or dir().
–...
How to detect Safari, Chrome, IE, Firefox and Opera browser?
...it's truly necessary, such as showing browser-specific instructions to install an extension. Use feature detection when possible.
Demo: https://jsfiddle.net/6spj1059/
// Opera 8.0+
var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >...
How to use “raise” keyword in Python [duplicate]
...dler, so that it can be handled further up the call stack.
try:
generate_exception()
except SomeException as e:
if not can_handle(e):
raise
handle_exception(e)
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Returning a C string from a function
...F-8 is an example of an mbcs. For the sake of intro, I quietly 'skip over' all of this.
Memory:
This means that a string like "my string" actually uses 9+1 (=10!) bytes. This is important to know when you finally get around to allocating strings dynamically.
So, without this 'terminating zero', y...
List all indexes on ElasticSearch server?
I would like to list all indexes present on an ElasticSearch server. I tried this:
22 Answers
...
What APIs are used to draw over other apps (like Facebook's Chat Heads)?
...t Heads on Android? What is the API to create the floating views on top of all other views?
3 Answers
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