Conversion int - binary

Question

Hello everybody,
i want to change an integer signed value (on 32 bits) in binary format and do the reverse operation.
So i wrote :
String binIntStr = Integer.toBinaryString(-1610612462);
System.out.println("Binary : "+binIntStr);
System.out.println("Int : "+Integer.parseInt(binIntStr, 2));The conversion of the int to binary runs correctly, but the reverse operation (binary string to int) throws an NumberFormatException.
I don't understand why the operation is well done in one way and is not allowed in the other.
The integer value is in good format (-2147483648 < -1610612462 < 2147483647) so why can't I change the binary string returned by the method toBinaryString in an integer ?

Answer 1

Integer.toBinaryString() returns a string representation of the integer argument as an unsigned integer in base 2
from the API doc
toBinaryString
public static String toBinaryString(int i)Returns a string representation of the integer argument as an unsigned integer in base 2.
The unsigned integer value is the argument plus 232 if the argument is negative; otherwise it is equal to the argument.
This value is converted to a string of ASCII digits in binary (base 2) with no extra leading 0s. If the unsigned magnitude is zero, it is represented by a single zero character '0' ('\u0030');
otherwise, the first character of the representation of the unsigned magnitude will not be the zero character. The characters '0' ('\u0030') and '1' ('\u0031') are used as binary digits.
Parameters:
i - an integer to be converted to a string.
Returns:
the string representation of the unsigned integer value represented by the argument in binary (base 2).so you will have to figure out out to deal with signed values yourself
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SomeoneElse