Java long type.
Information
Long types are so called signed two-complement numbers.
The 2 complement scheme allows both positive and negative integers to be represented.
The most significant bit of a two complement number is its sign bit.
The sign bit is 1 for negative numbers and 0 for positive numbers and for 0.
In Java the bytes are big-endian ordered, which means the most significant BYTE (where the sign bit is located) is always on the left side:
The long value range is: 264 = 18446744073709551616
Half of this number (18446744073709551616) are positive numbers ranging from:
>=0 and <=9223372036854775807
For example:
0x0000 0x0000 0x0000 0x0000 = 0
0x0000 0x0000 0x0000 0x0001 = 1
0x7FFF 0xFFFF 0xFFFF 0xFFFF = 9223372036854775807
The other half are negative numbers ranging from:
>=-9223372036854775808 and <0
For example:
0xFFFF 0xFFFF 0xFFFF 0xFFFF = -1
0x8000 0x0000 0x0000 0x0000= -9223372036854775808
To convert negative decimal values into hexadecimal values:
value = 264 + (neg_dec_value)
value = 18446744073709551616 + (neg_dec_value)
For example:
neg_dec_value= -1
value = 18446744073709551616 + (neg_dec_value) = 18446744073709551616 + (-1) = 18446744073709551615
The new decimal value 18446744073709551615 equals 0xFFFF 0xFFFF 0xFFFF 0xFFFF (Use your Windows calculator, to verify this).
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Long
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-9223372036854775808
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9223372036854775807
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