ProblemYou have a number of a larger type and you want to store it in a variable of a smaller type. SolutionCast the number to the smaller type. (A cast is a type listed in parentheses before a value that causes the value to be treated as though it were of the listed type.) For example, to cast a long to an int, you need a cast. To cast a double to a float, you also need a cast. DiscussionThis causes newcomers some grief, as the default type for a number with a decimal point is double, not float. So code like: float f = 3.0; won't even compile! It's as if you had written: double tmp = 3.0; float f = tmp; You can fix it by making f a double, by making the 3.0 a float, by putting in a cast, or by assigning an integer value of 3: double f = 3.0; float f = 3.0f; float f = 3f; float f = (float)3.0; float f = 3; The same applies when storing an int into a short, char, or byte: // CastNeeded.java public static void main(String argv[]) { int i; double j = 2.75; i = j; // EXPECT COMPILE ERROR i = (int)j; // with cast; i gets 2 System.out.println("i =" + i); byte b; b = i; // EXPECT COMPILE ERROR b = (byte)i; // with cast, i gets 2 System.out.println("b =" + b); } The lines marked EXPECT COMPILE ERROR do not compile unless either commented out or changed to be correct. The lines marked "with cast" show the correct forms. |