see also operators - bitwise shift operators
■ You cannot depict leading bits with the toBinaryString( ) method of the Integer wrapper class. Yes it can show integer bits. Unfortunately it does so without providing any leading zeroes. i.e.
byte x = 1;
System.out.print( Integer.toBinaryString( x ) ); prints just 1, not the 00000001 which you might have wanted
■ A quick rule to visually read a negative bit string as a decimal number is this:
Three steps: (1) Flip
the bits, (2) add in 1 more, then (3) read it as a (now negative)
number.
i.e. Let's read
1111 1111 1111 1001
which happens to represent minus seven. The presently-zero 2 bit plus the
presently-zero 4 bit both become one bits in the ensuing flip to 0000
0000 0000 0110, So that's 6 when the
bits are flipped after step one Then we
add in 1 more, in the second step, thus making it 7,
and thirdly we read it as a negative value.
That means you read it as a negative 7.
■ A quick rule to visually convert a positive bit string to negative is this:
Two steps: (1)
Subtract one, then (2) flip all the bits.
i.e. This rule says positive 1 should become all ones if negative. Let's see… Using a byte example, positive 0000 0001 becomes 0000 0000 in step one when 1 is subtracted. Then it does indeed become 1111 1111 in step two when its bits are flipped. And 1111 1111 is negative 1.