Module java.base

Package java.lang.foreign

Interface UnionLayout

All Superinterfaces:

GroupLayout, MemoryLayout

public sealed interface UnionLayout
extends GroupLayout

A group layout whose member layouts are laid out at the same starting offset.

Implementation Requirements:

Implementing classes are immutable, thread-safe and value-based.

Since:

22

Nested Class Summary

Nested classes/interfaces declared in interface java.lang.foreign.MemoryLayout

MemoryLayout.PathElement

Method Summary

Modifier and Type	Method	Description
UnionLayout	withByteAlignment(long byteAlignment)	Returns a memory layout with the same characteristics as this layout, but with the given alignment constraint (in bytes).
UnionLayout	withName(String name)	Returns a memory layout with the same characteristics as this layout, but with the given name.
UnionLayout	withoutName()	Returns a memory layout with the same characteristics as this layout, but with no name.

Methods declared in interface java.lang.foreign.GroupLayout

memberLayouts

Methods declared in interface java.lang.foreign.MemoryLayout

arrayElementVarHandle, byteAlignment, byteOffset, byteOffsetHandle, byteSize, equals, hashCode, name, scale, scaleHandle, select, sliceHandle, toString, varHandle

Method Details

withName

UnionLayout withName(String name)

Returns a memory layout with the same characteristics as this layout, but with the given name.

Specified by:

withName in interface GroupLayout

Specified by:

withName in interface MemoryLayout

Parameters:

name - the layout name

Returns:

a memory layout with the same characteristics as this layout, but with the given name

See Also:

• MemoryLayout.name()

withoutName

UnionLayout withoutName()

Returns a memory layout with the same characteristics as this layout, but with no name.

Specified by:

withoutName in interface GroupLayout

Specified by:

withoutName in interface MemoryLayout

Returns:

a memory layout with the same characteristics as this layout, but with no name

See Also:

• MemoryLayout.name()

withByteAlignment

UnionLayout withByteAlignment(long byteAlignment)

Returns a memory layout with the same characteristics as this layout, but with the given alignment constraint (in bytes).

Specified by:

withByteAlignment in interface GroupLayout

Specified by:

withByteAlignment in interface MemoryLayout

Parameters:

byteAlignment - the layout alignment constraint, expressed in bytes

Returns:

a memory layout with the same characteristics as this layout, but with the given alignment constraint (in bytes)

Throws:

IllegalArgumentException - if byteAlignment is not a power of two

IllegalArgumentException - if byteAlignment is less than M, where M is the maximum alignment constraint in any of the member layouts associated with this group layout