Java Arrays: Difference between revisions

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<span id='Array_Component'></span>An array instance contains a number of variables, called '''array components'''. The array components have no names, and they are referenced by array access expressions that use non-negative integer indices. The number of components of an array is fixed, once the array instance is created, the number of components cannot change. If the number of components of an array is zero, the array is said to be empty. If the array has n components, then it is said that the array has the length n. In this case, its components are referenced with zero-based indices from 0 to n-1. More details about accessing array components and elements are available in the [[#Array_Access|Array Access]] section below.  
<span id='Array_Component'></span>An array instance contains a number of variables, called '''array components'''. The array components have no names, and they are referenced by array access expressions that use non-negative integer indices. The number of components of an array is fixed, once the array instance is created, the number of components cannot change. If the number of components of an array is zero, the array is said to be empty. If the array has n components, then it is said that the array has the length n. In this case, its components are referenced with zero-based indices from 0 to n-1. More details about accessing array components and elements are available in the [[#Array_Access|Array Access]] section below.  


<span id='Component_Type'></span>The components can be of [[Java_Language#Primitive_Types|primitive types]] or [[Java_Language#Reference_Types|reference types]]. All components of an array have the '''same''' type, called the '''component type''' of the array. Multidimensional arrays are a special case where all the components have the same [[#Array_Type|array type]], which is in itself a reference type. More details about array types are available in the [[#Array_Types|Array Types]] section below.
<span id='Component_Type'></span>The components can be of [[Java_Language#Primitive_Types|primitive types]] or [[Java_Language#Reference_Types|reference types]]. All components of an array have the '''same''' type, called the '''component type''' of the array.  
 
Multidimensional arrays are a special case where all the components have the same [[#Array_Type|array type]], which is in itself a reference type. More details about array types are available in the [[#Array_Types|Array Types]] section below.





Revision as of 01:06, 2 November 2021

External

Internal

Overview

Array instances are objects. They are dynamically created, they can be assigned to a variable of type Object and all methods of class Object may be invoked on an array. More details about array creation are available in the Array Creation section below.

An array instance contains a number of variables, called array components. The array components have no names, and they are referenced by array access expressions that use non-negative integer indices. The number of components of an array is fixed, once the array instance is created, the number of components cannot change. If the number of components of an array is zero, the array is said to be empty. If the array has n components, then it is said that the array has the length n. In this case, its components are referenced with zero-based indices from 0 to n-1. More details about accessing array components and elements are available in the Array Access section below.

The components can be of primitive types or reference types. All components of an array have the same type, called the component type of the array.

Multidimensional arrays are a special case where all the components have the same array type, which is in itself a reference type. More details about array types are available in the Array Types section below.



array element

Array Types

An array type is a kind of a reference type. If the component type of an array is T, then the type of the array itself is written T[].

Array Variables

Array Creation

Array Creation with an Expression

Array Creation with an Array Initializer

Array Access

Multidimensional Arrays

A multidimensional array is an array of multidimensional arrays.

Bidimensional Arrays

Tridimensional Arrays