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Can enums be subclassed to add new elements?
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No, you can't do this in Java. Aside from anything else, d would then presumably be an instance of A (given the normal idea of "extends"), but users who only knew about A wouldn't know about it - which defeats the point of an enum being a well-known ...
Is there a way to instantiate a class by name in Java?
...ow to instantiate a class when having its name. Is there a way to do it in Java? I will have the package name and class name and I need to be able to create an object having that particular name.
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Android Studio - Ambiguous method call getClass()
...ac). This will navigate to a path such as $ANDROID_HOME/sources/android-20/java/lang/Object.java. Now, within IntelliJ or Android Studio:
Make Object.java writable by choosing File -> Make File Writable. You may be prompted to do this automatically if you try to edit the file.
Remove the unboun...
Truststore and Keystore Definitions
.... You can actually import a private key and a public certificate into the [java home]/jre/lib/security/cacerts default "truststore". The keytool utility does not make a distinction in the two terms, only in store types (i.e. - JKS vs. PKCS12). For that matter, Java does the same thing in the source ...
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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