Exercise 03: Default values of variables

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If variables are not initialized, they have a standard value. For example, the value of uninitialized boolean variable is “false”, but a standard value of an integer variable is 0…etc.

Read More: Java Primitive Data Types

Java exercise 03: Default values of variables

Level: Very easy

What is written to the standard output as the result of executing the following code?

public class DefaultValue
  int height;
  int width = 6;
  double wage;
  boolean isBig;
  String text;
  public static void main(String[] args)
    DefaultValue df = new DefaultValue();
    System.out.print(df.height + ", ");
    System.out.print(df.width + ", ");
    System.out.print(df.wage + ", ");
    System.out.print(df.isBig + ", ");
Author: Sar Maroof

Answer explanation

  1. The variables height, width, wage, isBig and the object text are not initialized.
  2. If variables are not initialized the value of int = 0, double = 0.0, boolean = false and object = null.

The correct answer is: 0, 6, 0.0, false, null.

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