array of arrays java code example

Example 1: Multidimensional array in java

// two dimensional string array in java example
public class TwoDimensionalStringArray 
{
   public static void main(String[] args) 
   {
      String[][] animals = {
              { "Lion", "Tiger", "Cheetah" },
              { "Deer", "Jackal", "Bear" },
              { "Hyena", "Fox", "Elephant" } };
      for(int a = 0; a < animals.length; a++) 
      {
         System.out.print(animals[a][0] + " ");
         for(int b = 1; b < animals[a].length; b++) 
         {
            System.out.print(animals[a][b] + " ");
         }
         System.out.println();
      }
   }
}

Example 2: how to declare an array in java

An array is an ordered collection of elements of the same type, identified by a pair of square brackets []. 
 
 To use an array, you need to:
1. Declare the array with a name and a type. Use a plural name for array, e.g., marks, rows, numbers. All elements of the array belong to the same type.
2. Allocate the array using new operator, or through initialization, e.g.
  
  int[] marks;  // Declare an int array named marks
              // marks contains a special value called null.
int marks[];  // Same as above, but the above syntax recommended
marks = new int[5];   // Allocate 5 elements via the "new" operator
// Declare and allocate a 20-element array in one statement via "new" operator
int[] factors = new int[20];
// Declare, allocate a 6-element array thru initialization
int[] numbers = {11, 22, 33, 44, 55, 66}; // size of array deduced from the number of items

Example 3: Arrays in java

// Accessing array elements using for loop
public class AccessingArrayElements
{
   public static void main(String[] args)
   {
      int[] arrNum = {25, 23, 15, 20, 24};
      for(int a = 0; a < arrNum.length; a++)
      {
         System.out.println(arrNum[a]);
      }
   }
}

Example 4: Multidimensional array in java

// create dynamic two dimensional array in java
import java.util.ArrayList;
import java.util.List;
public class Dynamic2dArray 
{
   public static void main(String[] args) 
   {
      List<int[]> li = new ArrayList<>();
      li.add(new int[]{2,4,6});
      li.add(new int[]{3,5});
      li.add(new int[]{1});
      // element at row 0, column 0
      System.out.println("Element at [0][0]: " + li.get(0)[1]);
      // get element at row : 1, column : 1
      System.out.println("Element at [1][1]: " + li.get(1)[1]);
   }
}

Example 5: Java create array of array

String[][] arrays = new String[][] { array1, array2, array3, array4, array5 };