package com.java_basics;

Date now = new Date();
String msg = "Hello World" + "!!";
arrays are references types hence the new operator
type value = reference type, array size.

• Arrays have a fixed length, which means new values can't be added to it.

  int[] numbers = new int[5]; 
  numbers[0] =1;
  numbers[1] =2;
  System.out.println(Arrays.toString(numbers));
  

// creating a 2-dimensional array to store a matrix. // every array is a row in dimensional arrays int[][] twoDimensionalArray = new int[2][3]; // by adding an extra [] increase the dimension of the array. twoDimensionalArray[0][0]= 3; twoDimensionalArray[0][1]= 5;

      System.out.println(Arrays.deepToString(twoDimensionalArray));

// System.out.println(msg.replace("!","*")); // final float pi = 3.14F;

// defining a constant // NB: the order of operation. // - () always evaluated first. // - /* secondly and // +- thirdly. // (10+3)*3 or 10+6 * 2 // ## Type casting. // - a short can hold 2 bytes, int 4 bytes, long 8 bytes // - all primitive types have a wrapper class for type casting String x = "2"; double y = 2.1 + Double.parseDouble(x); System.out.println(y); } }