- Enclosing interface:
MemorySegment
That is, a memory segment cannot be accessed if its associated scope is not alive. Scope instances can be compared for equality. That is, two scopes are considered equal if they denote the same lifetime.
The lifetime of a memory segment can be either unbounded or
bounded. An unbounded lifetime is modeled with the global scope.
The global scope is always alive
. As such, a segment associated
with the global scope features trivial temporal bounds and is always accessible.
Segments associated with the global scope are:
- Segments obtained from the global arena;
- Segments obtained from a raw address, using the
MemorySegment.ofAddress(long)
factory; and - Zero-length memory segments.
Conversely, a bounded lifetime is modeled with a segment scope that can be
invalidated, either explicitly
, or automatically, by the
garbage collector. A segment scope that is invalidated automatically is an
automatic scope. An automatic scope is always alive
as long as it is reachable.
Segments associated with an automatic scope are:
- Segments obtained from an automatic arena;
- Segments obtained from a Java array, e.g. using the
MemorySegment.ofArray(int[])
factory; - Segments obtained from a buffer, using the
MemorySegment.ofBuffer(Buffer)
factory; and - Segments obtained from loader lookup.
byte[] arr = new byte[10];
MemorySegment segment1 = MemorySegment.ofArray(arr);
MemorySegment segment2 = MemorySegment.ofArray(arr);
assert segment1.scope().equals(segment2.scope());
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Method Summary
Modifier and TypeMethodDescriptionboolean
Returnstrue
, if the provided object is also a scope, which models the same lifetime as that modeled by this scope.int
hashCode()
Returns the hash code of this scope object.boolean
isAlive()
Returnstrue
, if the regions of memory backing the memory segments associated with this scope are still valid.
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Method Details
-
isAlive
boolean isAlive()Returnstrue
, if the regions of memory backing the memory segments associated with this scope are still valid.- Returns:
true
, if the regions of memory backing the memory segments associated with this scope are still valid
-
equals
Returnstrue
, if the provided object is also a scope, which models the same lifetime as that modeled by this scope.. In that case, it is always the case thatthis.isAlive() == ((Scope)that).isAlive()
. -
hashCode
int hashCode()Returns the hash code of this scope object.- Overrides:
hashCode
in classObject
- Implementation Requirements:
- Implementations of this method obey the general contract of
Object.hashCode()
. - Returns:
- the hash code of this scope object
- See Also:
-