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Insert new column into table in sqlite?
...ault value can not be added in ALTER TABLE for some fieldtypes: sqlite.org/lang_altertable.html
– michel.iamit
Sep 9 '13 at 8:00
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Are Java static initializers thread safe?
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Yes, Java static initializers are thread safe (use your first option).
However, if you want to ensure that the code is executed exactly once you need to make sure that the class is only loaded by a single class-loader. Static ini...
How do I convert a Vector of bytes (u8) to a string
...nerally aren't good at asking questions, especially when they are new to a language. Rust makes a distinction between an array, a slice and a Vec, but newcomers don't know the differences. Make sure to upvote all questions and answers that prove useful though.
– Shepmaster
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Get keys from HashMap in Java
I have a Hashmap in Java like this:
14 Answers
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How to for each the hashmap? [duplicate]
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Lambda Expression Java 8
In Java 1.8 (Java 8) this has become lot easier by using forEach method from Aggregate operations(Stream operations) that looks similar to iterators from Iterable Interface.
Just copy paste below statement to your ...
When to use AtomicReference in Java?
...ing synchronized. In general, you're better off using synchronizers or the java.util.concurrent framework rather than bare Atomic* unless you know what you're doing.
Two excellent dead-tree references which will introduce you to this topic:
Herlihy's excellent Art of Multiprocessor Programming...
Understanding Spliterator, Collector and Stream in Java 8
I am having trouble understanding the Stream interface in Java 8, especially where it has to do with the Spliterator and Collector interfaces. My problem is that I simply can't understand Spliterator and the Collector interfaces yet, and as a result, the Stream interface is still somewha...
Using the “final” modifier whenever applicable in Java [closed]
In Java, there is a practice of declaring every variable (local or class), parameter final if they really are.
25 Answers
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How to specify JVM maximum heap size “-Xmx” for running an application with “run” action in SBT?
...rays processing and needs more memory than JVM gives by default. I know in Java it's specified by "-Xmx" option. How do I set SBT up to use particular "-Xmx" value to run an application with "run" action?
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Using Java 8's Optional with Stream::flatMap
The new Java 8 stream framework and friends make for some very concise java code, but I have come across a seemingly-simple situation that is tricky to do concisely.
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