These are the basics of arrays in Java.
An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed.

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Declaring:
<type>[] <name of array>=new <type>[<length of array>];
Example for integer & string:
int[] array1=new int[10];
String[] array2=new String[6];

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You can declare arrays of other types:

byte[] anArrayOfBytes;
short[] anArrayOfShorts;
long[] anArrayOfLongs;
float[] anArrayOfFloats;
double[] anArrayOfDoubles;
boolean[] anArrayOfBooleans;
char[] anArrayOfChars;
String[] anArrayOfStrings;

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Example of one array:
array1= 2 4 6 8 10
index 0 1 2 3 4

Each item in an array is called an element, and each element is accessed by its numerical index. Numbering begins with 0.
You can access a single element of array like this:
array1[2] <== this value is 6
You can normally change a value of any element of the array:
array1[2]=12

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I will take the most simple example of all. In the program I will define an array which has 6 elements of type integer (his length is 6). You enter those elements from keyboard and:
a. you just print them on the screen.
b. you print them on screen but backwards from the order you entered them.

I used Scanner class here instead of Keyboard class that I used often.

Very good explanation, but i have 2 negative critics :
-You should make it longer and more explained
-Those are not basics of arrays, those are basics of one-dimensional arrays !

These were just the basics that I've learnt.
This updated version contains some info from http://java.sun.com/.
Click HERE to visit the link to arrays on that page.

(12-08-2009 03:09 AM)Alphablend Wrote:  These are the basics of arrays in Java.
An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed.

---

Declaring:
<type>[] <name of array>=new <type>[<length of array>];
Example for integer & string:
int[] array1=new int[10];
String[] array2=new String[6];

---

You can declare arrays of other types:

byte[] anArrayOfBytes;
short[] anArrayOfShorts;
long[] anArrayOfLongs;
float[] anArrayOfFloats;
double[] anArrayOfDoubles;
boolean[] anArrayOfBooleans;
char[] anArrayOfChars;
String[] anArrayOfStrings;

---

Example of one array:
array1= 2 4 6 8 10
index 0 1 2 3 4

Each item in an array is called an element, and each element is accessed by its numerical index. Numbering begins with 0.
You can access a single element of array like this:
array1[2] <== this value is 6
You can normally change a value of any element of the array:
array1[2]=12

---

I will take the most simple example of all. In the program I will define an array which has 6 elements of type integer (his length is 6). You enter those elements from keyboard and:
a. you just print them on the screen.
b. you print them on screen but backwards from the order you entered them.

Code:

import java.util.Scanner;
public class example{
    public static void main(String[]args){
        Scanner scan=new Scanner(System.in);
        int[] array=new int[6];
        for (int i=0;i<6;i++)
        array[i]=scan.nextInt();
        //First task
        System.out.println("The order you entered them: ");
        for (int i=0;i<6;i++)
        System.out.println(array[i]);
        //Second task
        System.out.println("The reversed order: ");
        for(int i=5;i>=0;i--)
        System.out.println(array[i]);
    }
}

I used Scanner class here instead of Keyboard class that I used often.

You can make anything array even classes not just variables