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Java Constructor Inheritance
I was wondering why in java constructors are not inherited? You know when you have a class like this:
10 Answers
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What is a NullPointerException, and how do I fix it?
...n the most trivial cases, the compiler will catch the problem and let you know that "num may not have been initialized," but sometimes you may write code that does not directly create the object.
For instance, you may have a method as follows:
public void doSomething(SomeObject obj) {
//do someth...
Assign multiple columns using := in data.table, by group
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This now works in v1.8.3 on R-Forge. Thanks for highlighting it!
x <- data.table(a = 1:3, b = 1:6)
f <- function(x) {list("hi", "hello")}
x[ , c("col1", "col2") := f(), by = a][]
# a b col1 col2
# 1: 1 1 hi hello
# ...
Case statement with multiple values in each 'when' block
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I don't know why, but this strange situation happens: When I write this: when "toyota", "lexus", I get: unexpected tSTRING_BEG, expecting keyword_do or '{' or '(' (SyntaxError). However, when I write this: when "toyota","lexus", it...
Fragment or Support Fragment?
...isadvantage so far with this approach.
So my answer to my own question is now: When developing for Android 4.x, using the fragments from the support library is a good idea. The support library has bugs fixed that are still present in older fragment implementations and is frequently updated with mor...
Squash the first two commits in Git? [duplicate]
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Update July 2012 (git 1.7.12+)
You now can rebase all commits up to root, and select the second commit Y to be squashed with the first X.
git rebase -i --root master
pick sha1 X
squash sha1 Y
pick sha1 Z
git rebase [-i] --root $tip
This command can ...
Where is my .vimrc file?
... @Idigas I was typing :echo(xxx) on my command window but I realized now you meant to type this into the vim editor. However, even though :e xxx works, the :echo(xxx) doesn't. It says E121 Undefined Variable: xxx E15: Invalid Expression : ($xxx)
– Yannis Dran
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Why .NET String is immutable? [duplicate]
As we all know, String is immutable. What are the reasons for String being immutable and the introduction of StringBuilder class as mutable?
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iOS: how to perform a HTTP POST request?
...pple.com/library/mac/#documentation/Cocoa/Conceptual/… although if you know enough to mess around with different threads, you'll probably be fine.
– Aaron Brown
May 3 '12 at 21:53
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How to remove jar file from local maven repository which was added with install:install-file?
I use above command to install local jar into maven local repo. Now I have got the dependency from maven repo. I want to remove this from local repo. How to clean it ?
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