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Retrieving a List from a java.util.stream.Stream in Java 8
I was playing around with Java 8 lambdas to easily filter collections. But I did not find a concise way to retrieve the result as a new list within the same statement. Here is my most concise approach so far:
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Open Source Java Profilers [closed]
What can you guys recommend to use with Java?
12 Answers
12
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System.currentTimeMillis vs System.nanoTime
...you a nanosecond-precise time, relative to some arbitrary point.
From the Java Documentation:
public static long nanoTime()
Returns the current value of the most precise available system timer, in nanoseconds.
This method can only be used to
measure elapsed time and is not
related ...
Java8: Why is it forbidden to define a default method for a method from java.lang.Object
Default methods are a nice new tool in our Java toolbox. However, I tried to write an interface that defines a default version of the toString method. Java tells me that this is forbidden, since methods declared in java.lang.Object may not be default ed. Why is this the case?
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Java: Clear the console
Can any body please tell me what code is used for clear screen in Java? For example in C++
14 Answers
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How to initialize HashSet values by construction?
... Although most probably correct at the time of writing, as of Java 7 do use the Diamond operator as in: Set<String> h = new HashSet<>(Arrays.asList("a", "b")); public static final Set<String> MY_SET = new HashSet<>(Arrays.asList(SET_VALUES));
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List of Java class file format major version numbers?
I saw this list of major version numbers for Java in another post:
4 Answers
4
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How do I get a class instance of generic type T?
...there is no way to find out the runtime type of generic type parameters in Java. I suggest reading the chapter about type erasure in the Java Tutorial for more details.
A popular solution to this is to pass the Class of the type parameter into the constructor of the generic type, e.g.
class Foo<...
When should I use the “strictfp” keyword in java?
...e actually have an example of when you would use the strictfp keyword in Java? Has anyone actually found a use for this?
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.war vs .ear file
...on their functionality
JAR:
EJB modules which contain enterprise java beans (class files) and EJB deployment descriptor are packed as JAR files with .jar extension
WAR:
Web modules which contain Servlet class files, JSP Files, supporting files, GIF and HTML files are packaged as a...