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Create instance of generic type in Java?
Is it possible to create an instance of a generic type in Java? I'm thinking based on what I've seen that the answer is no ( due to type erasure ), but I'd be interested if anyone can see something I'm missing:
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Does Java casting introduce overhead? Why?
... casting is not feasible, JVM must throw a ClassCastException.
Taken from JavaWorld: The cost of casting
Casting is used to convert between
types -- between reference types in
particular, for the type of casting
operation in which we're interested
here.
Upcast operations (also cal...
What is the best way to filter a Java Collection?
I want to filter a java.util.Collection based on a predicate.
27 Answers
27
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java.lang.OutOfMemoryError: GC overhead limit exceeded [duplicate]
...t's needed. JVM enginner, Aleksey Shipilev has even a talk on this topic ("Java.lang.String Catechism").
– G. Demecki
Nov 4 '16 at 7:03
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How can I “pretty print” a Duration in Java?
Does anyone know of a Java library that can pretty print a number in milliseconds in the same way that C# does?
11 Answers
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How to avoid “ConcurrentModificationException” while removing elements from `ArrayList` while iterat
... Funny, I got same exception on String str = iter.next(); ! Java with collections sucks !
– Al-Mothafar
Jan 17 '15 at 14:23
1
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Java using enum with switch statement
...part you're missing is converting from the integer to the type-safe enum. Java will not do it automatically. There's a couple of ways you can go about this:
Use a list of static final ints rather than a type-safe enum and switch on the int value you receive (this is the pre-Java 5 approach)
Swit...
What are all the different ways to create an object in Java?
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There are four different ways to create objects in java:
A. Using new keyword
This is the most common way to create an object in java. Almost 99% of objects are created in this way.
MyObject object = new MyObject();
B. Using Class.forName()
If we know the name of the cla...
What does a tilde in angle brackets mean when creating a Java generic class?
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Just for personal clarification - IntelliJ produces Java source files with this notation, iaw, source files with illegal Java content??? Or is this just the view of the source and the saved file is correct?
– Andreas Dolk
Feb 3 '11 at 15:...
Does java have a int.tryparse that doesn't throw an exception for bad data? [duplicate]
... success of which is indicated by the boolean return value of the method. Java does not have an equivalent to the out parameter, thus the need for the if logic shown in this answer. msdn.microsoft.com/en-us/library/f02979c7(v=vs.110).aspx
– Peter Howe
Nov 24 ...