U

u1 as class file data type, 93
u2 as class file data type, 93
u4 as class file data type, 93
underflow

floating-point, Java virtual machine handling, 85
integer data types, not signaled by Java virtual machine, 85
Unicode

bibliographic reference, 5
characteristics, 5
UnknownError

as Java virtual machine error, 46
unloading

class or interface, 57
UnsatisfiedLinkError

See also binding; LinkageError; native method
definition, 45
thrown by

invokeinterface, 282
invokespecial, 287
invokestatic, 290
invokevirtual, 293
UnsupportedClassVersionError

definition, 49
UTF-8 format

See also CONSTANT_Utf8_info structure
bibliographic reference, 111
standard, differences between Java virtual machine UTF-8 strings and, 111