java - What can an Object[] array hold? -


i new java programming language , had question arrays. string[] arrays hold strings. array[] arrays hold other arrays. object[] array? clearly, these hold objects. but, since object superclass in java, mean object[] array can hold every type of object in java? in other words, can array hold objects child classes of object array created hold? can number[] array hold integer?

yes can learn lot trying small program:

public class example {     public static void main(string[] args) {         string string = "string";         integer integer = new integer(1);         int integerprimitive = 2;         float floatboxed = new float(1.23);         float floatprimitive = 1.23f;          // can hold different types inheriting object         object[] objects = new object[] {                  string,                  integer,                  integerprimitive,                 floatboxed,                  floatprimitive };          // can hold inherits number; cannot hold string         number[] numbers = new number[] {                  integer,                  integerprimitive,                  floatboxed,                 floatprimitive };          (int = 0; < objects.length; i++) {             system.out.println("objects[" + + "] = " + objects[i]);         }          (int = 0; < numbers.length; i++) {             system.out.println("numbers[" + + "] = " + numbers[i]);         }     } }

output:

objects[0] = string objects[1] = 1 objects[2] = 2 objects[3] = 1.23 objects[4] = 1.23 numbers[0] = 1 numbers[1] = 2 numbers[2] = 1.23 numbers[3] = 1.23

the key knowing array container can hold first observing if object types same or if object sub-class of array container type.

in question if number can hold integer, should see inheritance of integer in javadocs inherits number. can see number inherits object.

class number

class integer


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