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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Why does Java switch on contiguous ints appear to run faster with added cases?
I am working on some Java code which needs to be highly optimized as it will run in hot functions that are inv
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Rounding BigDecimal to *always* have two decimal places
I'm trying to round BigDecimal values up, to two decimal places. I'm using BigDecimal rounded = va
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How to evaluate a math expression given in string form?
I'm trying to write a Java routine to evaluate math expressions from String values like: "5+3" "10-40" "(
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How to round up the result of integer division?
I'm thinking in particular of how to display pagination controls, when using a language such as C# or Jav
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Fastest way to determine if an integer's square root is an integer
I'm looking for the fastest way to determine if a long value is a perfect square (i.e. its square root is
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How to set the DPI of Java Swing apps on Windows/Linux?
If you have an monitor with a DPI over 150 (such as Macbook Pro), you may also find the problem: the font on t
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Why aren't Java Collections remove methods generic?
Why isn't Collection.remove(Object o) generic? Seems like Collection<E> could have boolean remov
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Convert Enumeration to a Set/List
Is there some one-liner bridge method to dump a given Enumeration to java.util.List or java.util.Set? Somethin
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Difference between SPI and API?
What is the difference between Service Provider Interface (SPI) and Application Programming Interface (API)? M
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Compilation failed to complete:Program type already present
When compiling my project I get the following error message: Program type already present: com.google.androi
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How to read XML using XPath in Java
I want to read XML data using XPath in Java, so for the information I have gathered I am not able to parse XML
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How to pretty print XML from Java?
I have a Java String that contains XML, with no line feeds or indentations. I would like to turn it into a Str
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java.util.Date to XMLGregorianCalendar
Isn't there a convenient way of getting from a java.util.Date to a XMLGregorianCalendar?
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Jython, use only a method from Python from Java?
When reading and using this article it assumes that we have a full object definition with class and mapping (p
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Redux: How do I get Jython to use Python modules stored in Lib within its own jar file when running in Hadoop?
I'm attempting to use Jython for an implementation within Hadoop 1.2.1. I have seen strikingly little ab
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Why does this Jython loop fail after a single run?
I've got the following code: public static String getVersion() { PythonInterpreter interpreter = ne
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jython multithreading
I started studying python a couple of month ago, then I found Jython. Do threads work properly in Jython, sin
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Using NumPy and Cpython with Jython
I must use a commercial Java library, and would like to do it from Python. Jython is robust and I am fine with
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Jython and python modules
I've just started using the PythonInterpreter from within my Java classes, and it works great! However, i
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How can I call scikit-learn classifiers from Java?
I have a classifier that I trained using Python's scikit-learn. How can I use the classifier from a Java
