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How do I find out if first character of a string is a number?
...s, you must first be sure that the string isn't empty. If it is, charAt(0) and substring(0, 1) will throw a StringIndexOutOfBoundsException. startsWith does not have this problem.
To make the entire condition one line and avoid length checks, you can alter the regexes to the following:
s.matches("...
How do I delete NuGet packages that are not referenced by any project in my solution?
Somehow during the upgrade to VS2012 and .NET 4.5, I've managed to get NuGet confused. There are packages that appear in the package manager (and the packages folder) that I cannot delete (I believe they are legacy ASP.NET NuGet packages that have been replaced with new package names with the new v...
C++ Object Instantiation
I'm a C programmer trying to understand C++. Many tutorials demonstrate object instantiation using a snippet such as:
9 An...
How can I make an “are you sure” prompt in a Windows batchfile?
...h file that automates copying a bunch of files from one place to the other and back for me. Only thing is as much as it helps me I keep accidentally selecting that command off my command buffer and mass overwriting uncommited changes.
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What exactly do “u” and “r” string flags do, and what are raw string literals?
...no "escape sequences" to represent newlines, tabs, backspaces, form-feeds, and so on. In normal string literals, each backslash must be doubled up to avoid being taken as the start of an escape sequence.
This syntax variant exists mostly because the syntax of regular expression patterns is heavy w...
How does Junit @Rule work?
...n a more generic way.
For instance, ExternalResource executes code before and after a test method, without having to use @Before and @After. Using an ExternalResource rather than @Before and @After gives opportunities for better code reuse; the same rule can be used from two different test classes....
Adding :default => true to boolean in existing Rails column
... that you would have to create a rake task or just go in the rails console and update all the records (which I would not recommend in production).
When you added t.boolean :show_attribute, :default => true to the create_profiles migration, it's expected that it didn't do anything. Only migrations...
The role of #ifdef and #ifndef
In this what is the role of #ifdef and #ifndef , and what's the output?
4 Answers
4...
Best way to compare two complex objects
I have two complex objects like Object1 and Object2 . They have around 5 levels of child objects.
15 Answers
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Why cannot cast Integer to String in java?
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Why this is not possible:
Because String and Integer are not in the same Object hierarchy.
Object
/ \
/ \
String Integer
The casting which you are trying, works only if they are in the same hierarchy, e.g.
Object
/
/...