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javaunsigned

How to put unsigned float into ByteBuffer?

I'm trying to handle unsigned primitives number with ByteBuffer.

I can handle (put into ByteBuffer) unsigned byte/short/int. For example, the code to handle unsigned int:

m_buf.putInt(nOffset, (int) (0xFFFFFFFF & number.longValue()));

but, when I want to do the same for unsigned float:

m_buf.putFloat(nOffset, (float) (0xFFFFFFFF & number.doubleValue()));

I'm getting compiler error: "The operator & is undefined for the argument type(s) int, double"

So - How can I handle get and set unsigned float number with ByteBuffer?

Thanks

Solution

  • The IEEE 754 floating point representation has 1 bit reserved for the sign. There is no alternative representation that uses this bit as part of the mantissa or exponent. In other words, there is no "unsigned float".

    If all you want to do is to make sure you don't put any negative numbers in the buffer, just do

    m_buf.putFloat(nOffset, Math.abs(number.floatValue()));