Widening and narrowing conversions, casting and numeric promotion rules

A widening primitive conversion moves a value into a type that can hold a larger range, and Java does it automatically. The widening chain is byte to short to int to long to float to double, with char also widening to int and beyond. Widening from int or long to float, or from long to double, is allowed even though it can lose precision in the low digits, because the range still fits. Note that byte and short do not widen to char, and char does not widen to short, because char is unsigned.