Public int indexOf(int ch, int fromIdx) doesn't work for some decimal value

Question

I have tested two strings below. These two string are identical, except the first string has a char 'ƒ, which has a decimal value of 131. And the second string has a char 'À', which has a decimal value of 192. I am expecting the same output, which is 11, but I got -1 for the test I did using the first string. In the API for public int indexOf(int ch, int fromIndex), values of ch is in the range from 0 to 0xFFFF (inclusive). It is highly appreciated if anyone could provide any insights on why -1 returned when the first string is tested. Thank you in advance.
String strHasDecimal131 = "Test value ƒ, it has a decimal value of 131";
String strHasDecimal192 = "Test value À, it has a decimal value of 192";
int badDecimal = 131;
int idxBadDecimal = strHasDecimal131.indexOf( badDecimal, 0);
System.out.println( "index of Bad Decimal: " + idxBadDecimal );
The output is: index of Bad Decimal -1
int badDecimal = 192;
int idxBadDecimal = strHasDecimal192.indexOf( badDecimal, 0);
System.out.println( "index of Bad Decimal: " + idxBadDecimal );
The output is: index of Bad Decimal: 11

Answer 1

Thank you everyone for your inputs. Following are the print statements and the output: for character 'ƒ' and ' À':
System.out.println((int)'\u0083' + ", " + (int)'\u00C0' + " print decimal value" );
Output: 131, 192 print decimal value
System.out.println((char)'\u0083' + ", " + (char)'\u00C0' + " print character value" );
Output: ?, À print character value
According to Latin-1 Supplement table, the first char in the output would have the appearance of ƒ, instead it has the appearance of ?
System.out.println( (int)'ƒ' + ", "+ (int)'À' + " print integer value");
Output: 402, 192 print integer value
I also have tried to print out the decimal value of following char: € � ‚ ƒ „ … † ‡, according to Latin-1 Supplement table, these char has decimal value of 128 through 135 and hex value 0x0080 through 0x0087. And the output from java println is: 8364 65533 8218 8222 8230 402 8224 8225.
System.out.println((int)'€' + " " + (int)'�' + " " + (int)'‚' + " " +(int)'„' + " " + (int)'…' + " " +(int)'ƒ' + " " + (int)'†' + " " + (int)'‡' );
As I did before, I print out character of decimal value of 128 through 135
System.out.println((char)128 + " " + (char)129 + " " + (char)130 + " " +(char)131 + " " + (char)132 + " " +(char)133 + " " + (char)134 + " " + (char)135 );
Output: ? ? ? ? ? ? ? ?
Not sure why java prints character for decimal value of 128 through 159 differently from what appears in the Latin-1 Supplement table. Any of your inputs are appreciately.