net.openhft.chronicle.values

Annotation Type Align

@Target(value=METHOD)
 @Retention(value=RUNTIME)
 @Documented
public @interface Align

Specifies the fields' arrangement in native implementation should be so that the offset to the aligned field bytes from the beginning of the instance is a multiple of the specified offset(), the range of the field's bytes offsets don't cross the specified dontCross() boundary. This annotation should be put on any single method accessing the field: getter, or setter, or adder, etc.

This annotation guarantees alignment from the beginning of the instance, so to ensure alignment in the native memory, the instance as a whole should be aligned by native memory addresses to the most coarse alignment of it's fields.

The default alignment depends on the field type, see DEFAULT.

Field Summary

Fields

Modifier and Type	Fields and Description
static int	DEFAULT If the field type is an integer or a floating point primitive, default dontCross() alignment is equivalent to 1-byte for fields which take <= 8 bits, 2-byte for fields which take <= 16 bits, 4-byte for fields which take <= 32 bits, 8-byte for fields which take <= 64 bits.
static int	NO_ALIGNMENT 0 represents no particular alignment (shouldn't align the field start, shouldn't track crossing of any border).

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
int	dontCross The field's bytes shouldn't cross the dontCross boundary.
int	offset The offset to the field's bytes should be a multiple of the offset.

Field Detail

DEFAULT

public static final int DEFAULT

• If the field type is an integer or a floating point primitive, default dontCross() alignment is equivalent to 1-byte for fields which take <= 8 bits, 2-byte for fields which take <= 16 bits, 4-byte for fields which take <= 32 bits, 8-byte for fields which take <= 64 bits. offset() alignment is 1-byte for such fields.
• If the field is another value interface, default offset alignment is ValueModel.recommendedOffsetAlignment() for this sub-value interface. dontCross default alignment for Value fields is NO_ALIGNMENT.
• If the field is an array, default offset alignment is equivalent to the maximum of it's element offset or dontCross alignment, default dontCross for array fields is NO_ALIGNMENT.
• If the field is of CharSequence type, default dontCross alignment is NO_ALIGNMENT. Default offset alignment is not applicable for CharSequence fields, must be specified explicitly.
• If the field is of boolean type, default alignment is not applicable, both offset and dontCross alignment values must be specified explicitly.

NO_ALIGNMENT

public static final int NO_ALIGNMENT

0 represents no particular alignment (shouldn't align the field start, shouldn't track crossing of any border).

Element Detail

offset

public abstract int offset

The offset to the field's bytes should be a multiple of the offset.

Default:

-1

dontCross

public abstract int dontCross

The field's bytes shouldn't cross the dontCross boundary.

Default:

-1