Boxing and Unboxing : Autobox Unbox « Data Type « Java Tutorial






  1. Java Tutorial
  2. Data Type
  3. Autobox Unbox
  1. Boxing refers to the conversion of a primitive to a corresponding wrapper instance, such as from an int to a java.lang.Integer.
  2. Unboxing is the conversion of a wrapper instance to a primitive type, such as from Byte to byte.
public class MainClass{

  public static void main(String[] args){
     
     Integer number = new Integer (100);
     int [] ints = new int [2];
     ints [0] = number;
  }

}








2.18.Autobox Unbox
2.18.1.Type conversion (JDK1.5 Autoboxing/Unboxing)
2.18.2.Boxing and Unboxing
2.18.3.Autoboxing and Auto-Unboxing
2.18.4.Manually boxes the value 100 into an Integer
2.18.5.The modern way to construct an Integer object that has the value 100
2.18.6.To unbox an object
2.18.7.Autoboxing/unboxing: an argument passed to a method or returned from a method
2.18.8.Autoboxing/unboxing occurs inside expressions
2.18.9.Auto-unboxing: mix different types of numeric objects in an expression.
2.18.10.Using an integer object to control a switch statement
2.18.11.Autoboxing/Unboxing Boolean and Character Values
2.18.12.Autoboxing/unboxing takes place with method parameters and return values.
2.18.13.Auto-unboxing allows you to mix different types of numeric objects in an expression.