Java
Java (not to be confused with JavaScript or JScript or JS) is a general-purpose object-oriented programming language designed to be used in conjunction with the Java Virtual Machine (JVM). "Java platform" is the name for a computing system that has installed tools for developing and running Java programs. Use this tag for questions referring to the Java programming language or Java platform tools.
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How do I call one constructor from another in Java?
Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? An
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How do I determine whether an array contains a particular value in Java?
I have a String[] with values like so: public static final String[] VALUES = new String[] {"AB","BC","CD","AE
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Does a finally block always get executed in Java?
Considering this code, can I be absolutely sure that the finally block always executes, no matter what somethi
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How can I fix 'android.os.NetworkOnMainThreadException'?
I got an error while running my Android project for RssReader. Code: URL url = new URL(urlToRssFeed); SAXPa
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How can I create an executable JAR with dependencies using Maven?
I want to package my project in a single executable JAR for distribution. How can I make a Maven project pack
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Why is printing "B" dramatically slower than printing "#"?
I generated two matrices of 1000 x 1000: First Matrix: O and #. Second Matrix: O and B. Using the following
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How do I test a private function or a class that has private methods, fields or inner classes?
How do I unit test (using xUnit) a class that has internal private methods, fields or nested classes? Or a fun
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Initialization of an ArrayList in one line
I wanted to create a list of options for testing purposes. At first, I did this: ArrayList<String> plac
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What is a serialVersionUID and why should I use it?
Eclipse issues warnings when a serialVersionUID is missing. The serializable class Foo does not declare
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How do I convert a String to an int in Java?
How can I convert a String to an int in Java? My String contains only numbers, and I want to return the numbe
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When to use LinkedList over ArrayList in Java?
I've always been one to simply use: List<String> names = new ArrayList<>(); I use the inte
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What is the difference between public, protected, package-private and private in Java?
In Java, are there clear rules on when to use each of access modifiers, namely the default (package private),
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How can I create a memory leak in Java?
I just had an interview where I was asked to create a memory leak with Java. Needless to say, I felt pretty du
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How do I efficiently iterate over each entry in a Java Map?
If I have an object implementing the Map interface in Java and I wish to iterate over every pair contained wit
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Why is char[] preferred over String for passwords?
In Swing, the password field has a getPassword() (returns char[]) method instead of the usual getText() (retur
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Why don't Java's +=, -=, *=, /= compound assignment operators require casting?
Until today, I thought that for example: i += j; Was just a shortcut for: i = i + j; But if we try this:
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How do I generate random integers within a specific range in Java?
How do I generate a random int value in a specific range? I have tried the following, but those do not work: A
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Create ArrayList from array
I have an array that is initialized like: Element[] array = {new Element(1), new Element(2), new Element(3)};
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What are the differences between a HashMap and a Hashtable in Java?
What are the differences between a HashMap and a Hashtable in Java? Which is more efficient for non-threaded
