Parsing a Hexadecimal String to an Integer throws a NumberFormatException?

Will this help?

Integer.parseInt("00ff00", 16)

16 means that you should interpret the string as 16-based (hexadecimal). By using 2 you can parse binary number, 8 stands for octal. 10 is default and parses decimal numbers.

In your case Integer.parseInt(primary.getFullHex(), 16) won't work due to 0x prefix prepended by getFullHex() - get rid of and you'll be fine.

Integer.valueOf(string) assumes a decimal representation. You have to specify that the number is in hex format, e.g.

int value = Integer.valueOf("00ff0000", 16); 

Note that Integer.valueOf(string,16); does not accept a prefix of 0x. If your string contains the 0x prefix, you can use Integer.decode("0x00ff0000");

Try to use decode method:

Integer.decode("0x00ff00");

DecodableString:

• Signopt DecimalNumeral
• Signopt 0x HexDigits
• Signopt 0X HexDigits
• Signopt # HexDigits
• Signopt 0 OctalDigits

You can read about it here https://docs.oracle.com/javase/7/docs/api/java/lang/Integer.html#decode(java.lang.String)

The parseInt method only accepts the number part, not any kind of "base" indicator such as "0x" for hexadecimal or "0" for octal. Use it like this

int decimal = Integer.parseInt("1234", 10);
int octal = Integer.parseInt("1234", 8);
int hex = Integer.parseInt("1234", 16);