How to convert decimal negative number to binary?

Question

Java

How to implement it?
Everything is clear with positive ones, but I don’t know what to do with negative ones.
I could only get the reverse code of the number, but the last step, addition 1, led me to a dead end.
I saw implementations in PASCAL and C, I need in JAVA

Answer 1

Given: -128
1. Make a negative number positive
-128 => 128 (10000000)
2. Negate all bits
128 (10000000) => 127 (01111111)
3. Add 1 to the resulting number
127 (01111111) => -128 (10000000 )

Answer 2

and what is there? you invert all bits and you add unit to this number. this is how "two compliment" works

Answer 3

I did not quite understand the question, because the solution itself is contained in it.
I will make an assumption that it is not clear - why is one added to the inverted value?

Answer 4

Need to write. What exactly is the problem is not clear.