LocationIdentity

java.lang.Object
- org.graalvm.word.LocationIdentity

```
public abstract class LocationIdentity
extends Object
```
Marker interface for location identities. A different location identity of two memory accesses guarantees that the two accesses do not interfere.
Clients of LocationIdentity must use Object.equals(Object), not ==, when comparing two LocationIdentity values for equality. Likewise, they must not use IdentityHashMaps with LocationIdentity values as keys.

Since:

19.0

Field Summary

Fields
Modifier and Type	Field and Description
`static LocationIdentity`	`ANY_LOCATION` Indicates that the given location is the union of all possible mutable locations.
`static LocationIdentity`	`INIT_LOCATION` Location only allowed to be used for writes.

Constructor Summary

Constructors
Modifier Constructor and Description

protected LocationIdentity()
Creates a new location identity.

Constructors
Modifier	Constructor and Description
`protected`	`LocationIdentity()` Creates a new location identity.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static LocationIdentity`	`any()` Indicates that the given location is the union of all possible mutable locations.
`static LocationIdentity`	`init()` Location only allowed to be used for writes.
`boolean`	`isAny()` Returns true if this location identity is `LocationIdentity.any()`.
`abstract boolean`	`isImmutable()` Denotes a location is unchanging in all cases.
`boolean`	`isInit()` Returns true if this location identity is `LocationIdentity.init()`.
`boolean`	`isMutable()` The inversion of `LocationIdentity.isImmutable()`.
`boolean`	`isSingle()` Returns true if this location identity is not `LocationIdentity.any()`.
`boolean`	`overlaps(LocationIdentity other)` Returns true if the memory slice denoted by this location identity may overlap with the provided other location identity.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - ANY_LOCATION
```
public static final LocationIdentity ANY_LOCATION
```
    Indicates that the given location is the union of all possible mutable locations. A write to such a location kill all reads from mutable locations and a read from this location is killed by any write (except for initialization writes).
    
    Since:
    
    19.0
  - INIT_LOCATION
```
public static final LocationIdentity INIT_LOCATION
```
    Location only allowed to be used for writes. Indicates that a completely new memory location is written. Kills no read. The previous value at the given location must be either uninitialized or null. Writes to this location do not need a GC pre-barrier.
    
    Since:
    
    19.0
- Constructor Detail
  - LocationIdentity
```
protected LocationIdentity()
```
    Creates a new location identity. Subclasses are responsible to provide proper implementations of Object.equals(java.lang.Object) and Object.hashCode().
    
    Since:
    
    19.0
- Method Detail
  - any
```
public static LocationIdentity any()
```
    Indicates that the given location is the union of all possible mutable locations. A write to such a location kill all reads from mutable locations and a read from this location is killed by any write (except for initialization writes).
    
    Since:
    
    19.0
  - init
```
public static LocationIdentity init()
```
    Location only allowed to be used for writes. Indicates that a completely new memory location is written. Kills no read. The previous value at the given location must be either uninitialized or null. Writes to this location do not need a GC pre-barrier.
    
    Since:
    
    19.0
  - isImmutable
```
public abstract boolean isImmutable()
```
    Denotes a location is unchanging in all cases. Not that this is different than the Java notion of final which only requires definite assignment.
    
    Since:
    
    19.0
  - isMutable
```
public final boolean isMutable()
```
    The inversion of LocationIdentity.isImmutable().
    
    Since:
    
    19.0
  - isAny
```
public final boolean isAny()
```
    Returns true if this location identity is LocationIdentity.any().
    
    Since:
    
    19.0
  - isInit
```
public final boolean isInit()
```
    Returns true if this location identity is LocationIdentity.init().
    
    Since:
    
    19.0
  - isSingle
```
public final boolean isSingle()
```
    Returns true if this location identity is not LocationIdentity.any().
    
    Since:
    
    19.0
  - overlaps
```
public final boolean overlaps(LocationIdentity other)
```
    Returns true if the memory slice denoted by this location identity may overlap with the provided other location identity.
    
    Since:
    
    19.0

Class LocationIdentity

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

ANY_LOCATION

INIT_LOCATION

Constructor Detail

LocationIdentity

Method Detail

any

init

isImmutable

isMutable

isAny

isInit

isSingle

overlaps