Different ways to initialize arrays in java

By Sidd Bhattacharjee -

Array Initialization in Java

Different ways to initialize array's in java
Java Arrays can be populated in a number of ways following summarizes different options.
One item at a time using a loop
Following example we are declaring rolNumms array of size 10 and adding one item at a time using a for a loop.
  //Using For loops
   int rollNums[] = new int[10];
   for (int i=0; i
At the Time of Declaration
We can set the content of the array while declaring the array it self. Both the syntax will result in initializing the array with 10 items. Note that when we provide the initializer while declaring the size of the array cannot be specified.
int rollNums2[] = new int[] {1, 2, 3, 4, 5, 6, 7, 8, 9 ,10};
int rollNums3[] = {1, 2, 3, 4, 5, 6, 7, 8, 9 ,10};
Arrays.setAll() and Generator function
We can set the content of the array using the Arrays.setAll() method as well.
int rollNums4 [] = new int [10];
Arrays.setAll(rollNums4, p -> p );
Copying another array
We can also copy an existing array to populate a new array, using java.util.Arrays.copyOf method
int rollNums5[] = Arrays.copyOf(rollNums4, rollNums4.length);

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