Questions tagged [initialization-block]

Questions related to initialization block. Their order of execution in case of multiple blocks, their default values etc

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Static Initialization Blocks

As far as I understood the "static initialization block" is used to set values of static field if it cannot be done in one line. But I do not understand why we need a special block for that. For example we declare a field as static (without a value…
Roman
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What is the difference between init block and constructor in kotlin?

I have started learning Kotlin. I would like to know the difference between init block and constructor. What is the difference between this and how we can use this to improve? class Person constructor(var name: String, var age: Int) { var…
Samir Bhatt
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What is an initialization block?

We can put code in a constructor or a method or an initialization block. What is the use of initialization block? Is it necessary that every java program must have it?
Sumithra
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Use of Initializers vs Constructors in Java

So I've been brushing up on my Java skills as of late and have found a few bits of functionality that I didn't know about previously. Static and Instance Initializers are two such techniques. My question is when would one use an initializer instead…
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Static block vs. initializer block in Java?

Possible Duplicate: Static Initialization Blocks Consider the following code: public class Test { { System.out.println("Empty block"); } static { System.out.println("Static block"); } public static void…
Anshu
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Java Instance Initialization Block and instance variables

In context to my previous question Java classes and static blocks what if I changed my code from static block and variables to normal Instance Initialization Block and instance variables. Now how would the code be executed? class extra3 { public…
Shashank Agarwal
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when does a static initializer block executes in java?

public class Parent { public static int y=10 ; } public class Child extends Parent { static { y=20 ; } public static void main(String[] args) { System.out.println(Child.y); // output = 20 } } public class Test…
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Instance initialization block and subclasses

I'm getting confused about when the instance initialization block should run. According to Kathy Sierra's book: Instance init blocks run every time a class instance is created So, consider having two classes: a parent and a child, according to…
a.u.r
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Why does encasing variable initialization into an initialization block allow initialization before declaration?

Consider the following code: class New { id = 2; int id = 7; } Obviously it won't compile as we attempt to initialize an undeclared variable. Encasing the statement into an initialization block, however, makes it compile…
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How to break out initialization block?

I have a class looks like this class Some { private enum Inner { } } And I'm trying to find the Inner class in a initialization block of my test class. class SomeTest { private static final Class INNER_CLASS; { for…
Jin Kwon
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Can static class contains instance initialization block?

While reading Java I came across one question: Can a static class contains instance initialization block?