In Java, a 3D array is a multidimensional array with three dimensions. It is an array of arrays of arrays. Here's an example of how you can declare and initialize a 3D array in Java: int[][][] threeDArray = new int[3][4][2]; // Assign values to the elements in the 3D array threeDArray[0][0][0] = 1; threeDArray[0][0][1] = 2; threeDArray[0][1][0] = 3; threeDArray[0][1][1] = 4; // Access and print the value of an element in the 3D array int value = threeDArray[0][1][1]; System.out.println(value); // Output: 4 In this example, we declare a 3D array `threeDArray` with dimensions 3, 4, and 2. We then assign values to specific elements in the array using indices, and finally, we access and print the value of an element in the array.