O

Object class

definition, 12
objects

See also array; instances
definition, 11
opcodes

definition, 80
mnemonics by opcode (table), 415
reserved, 172
operand stack

allocation, 73
code verification, Pass 3 - bytecode verifier, 143
data-flow analysis, 142
definition, 73
duplicating value(s)

dup, 218
dup_x1, 219
dup_x2, 220
dup2, 221
dup2_x1, 222
dup2_x2, 223

frames used to hold, 73
management instruction summary, 88
merging, during data-flow analysis, 145
pop value(s)

pop, 346
pop2, 347

size limitation, 152
structural constraints on instructions, 137
swap values, swap, 357
operand(s)

constraints, static, 134
definition, 80
implicit, compilation advantage of, 366
instructions, verification process, 143
Java virtual machine instructions, storage order and alignment, 80
types, how distinguished by Java virtual machine instruction set, 62
optimization

alternative instruction use, 143
ordered values

NaN values not ordered, implications of, 65
ORing

int

bitwise, exclusive, ixor, 303
bitwise, inclusive, ior, 294

long

bitwise, exclusive, lxor, 334
bitwise, inclusive, lor, 325
outer_class_info_index item

(classes array of InnerClasses_attribute structure), 126
OutOfMemoryError

heap-related error, 69
as Java virtual machine error, 45
Java virtual machine stack-related error, 68
method area-related error, 69
native method stack-related error, 71
runtime constant pool-related error, 70
when thrown during initialization, 54
overflow

floating-point, Java virtual machine handling, 85
heap, 69
integer data types, not detected by Java virtual machine, 85
Java virtual machine stack, 68
method area, 69
native method stack, 71
runtime constant pool, 70
overriding

ACC_FINAL flag, method_info structure prevention of, 115
definition, 26
in interfaces, 37
methods, 31