how to create an array in java
int[] array1 = new int[5]; //int array length 5
String[] array2 = new String[5] //String array length 5
double[] array3 = new double[5] // Double array length 5
how to create an array in java
int[] array1 = new int[5]; //int array length 5
String[] array2 = new String[5] //String array length 5
double[] array3 = new double[5] // Double array length 5
arrays in java
3 data structures:
1. Array 2. Collection 3. Maps
Arrays: a variable that can have multiple data
DataType[] variableName = { dat1, data2, data3 };
the data we are storing MUST match with DataTyp
each data in the array has its own index number
initializing the size of the array:
1. giving the values: size will be initialized automatically
int[] arr = {10, 20, 30};
2. giving the size only: default value of the datatype will be assigned at each index
int[] arr = new int[length];
int[] arr = new int[5];
default values: byte, short, int, long ==> 0
String or any object ==> null
length: returns the length of array
Array' size is fixed
Arrays utilities:
length: returns total number of the element of the arra
Arrays Utilities:
Arrays class: presented in "java.util"
import java.util.Arrays;
Arrays.toString(arrayName): converts the array to String, returns the string
Arrays.sort(arrayName): sorts the given array in ascending order
Arrays.equals(arr1, arr2): chekcs if the two arrays are same or not. returns boolean
toCharArray(): returns char array from the string
String str = "Batch 18";
char[] ch = str.toCharArray(); //['B', 'a', 't', 'c', 'h', ' ', '1', '8']
Array: size is fixed
supports primitives and objects
Can be multi-dimensional
has index, accept duplicates
Arrays.sort(arrayName);
Collections.sort()
Copyright © 2021 Codeinu
Forgot your account's password or having trouble logging into your Account? Don't worry, we'll help you to get back your account. Enter your email address and we'll send you a recovery link to reset your password. If you are experiencing problems resetting your password contact us