Can someone please explain to me what is going on here:
char c = '+'; int i = (int)c; System.out.println("i: " + i + " ch: " + Character.getNumericValue(c));
i: 43 ch:-1. Does that mean I have to rely on primitive conversions to convert
int? So how can I convert a
Edit: Yes I know
-1 if it is not a numeric value and that makes sense to me. The question is: why does doing primitive conversions return
43 is the ASCII for
+, but I would expect the cast to not succeed just like
getNumericValue did not succeed. Otherwise that means there are two semantic equivalent ways to perform the same operation but with different results?
This question is related to
java.lang.Character.getNumericValue(char ch) returns the
int value that the specified Unicode character represents. For example, the character
'\u216C' (the roman numeral fifty) will return an int with a value of 50.
The letters A-Z in their uppercase
('\u0041' through '\u005A'), lowercase
('\u0061' through '\u007A'), and full width variant
('\uFF21' through '\uFF3A' and '\uFF41' through '\uFF5A') forms have numeric values from 10 through 35. This is independent of the Unicode specification, which does not assign numeric values to these char values.
This method returns the numeric value of the character, as a nonnegative int value;
-2 if the character has a numeric value that is not a nonnegative integer;
-1 if the character has no numeric value.
And here is the link.