bastore :
store in byte/boolean array : index : visitInsn()
- Description
- Takes a 32-bit int from the stack, truncates it to an 8-bit signed byte,
and stores it in an array of bytes. arrayref is a reference to an array
of bytes. index is an int. value is the int value to be stored in
the array. arrayref, index and value are removed from the
stack, and value is truncated to 8 bits and stored in the array at the
given index.
bastore is also used to store values in boolean arrays. In this case,
arrayref is a reference to an array of booleans (see the
newarray instruction) . If value is zero, false is stored at
the given index in the array, otherwise true is stored at the given
index. In Sun's implementation, boolean arrays are actually stored as byte
arrays, using one byte per boolean value. Other implementations might use
packed arrays - or even int arrays - this is invisible to programs running on
the JVM, which always use baload and bastore to access and store values in
boolean arrays. - Exceptions
- NullPointerException - arrayref is null
ArrayIndexOutOfBoundsException - index is < 0 or >=
arrayref.length - Notes
- 2. Array indices start at 0 (the first entry in the array is at
index 0).
- See also
- iastore lastore fastore dastore aastore castore sastore iaload laload faload daload aaload baload caload saload newarray
- Stack
|
Before
|
After |
| value |
... |
| index |
... |
| arrayref |
... |
| ... |
... |
- Bytecode
|
Type
|
Description |
|
u1
|
bastore
opcode = 0x54 (84)
|