UnsupportedOperationException with converting byte[] to float[]

Question

I\'m trying to convert a byte[] to a float[] by putting the byte[] in a ByteBuffer, converting this to a FloatBuffer (.asFloatBuffer), and then converting this to a

Answer 1

The simple way to get a float from a byte[] array wrapped by a ByteBuffer is to use getFloat() which reads the next 4 bytes and returns the generated float. You can do this in a loop, if your byte[] contains more than 4 bytes. Note that the method throws

BufferUnderflowException - If there are fewer than four bytes remaining in this buffer

You can get it from the FloatBuffer as well

buffer.asFloatBuffer().get();

if you want but array() throws an UnsupportedOperationException if the instance's hb field is null. If you look at the source code from Oracle JDK 7, there is a comment

final float[] hb;  // Non-null only for heap buffers

If you run your code, you will notice the returned FloatBuffer is a ByteBufferAsFloatBufferB, not a HeapFloatBuffer.