Package org.graalvm.polyglot.proxy

Interface ProxyHashMap

All Superinterfaces:

Proxy

public interface ProxyHashMap
extends Proxy

Interface to be implemented to mimic guest language hash maps.

Since:

21.1

See Also:

• Proxy

Method Summary

Modifier and Type	Method	Description
static ProxyHashMap	from(Map<Object,Object> values)	Creates a proxy hash map backed by a Java Map.
Object	getHashEntriesIterator()	Returns the hash entries iterator.
long	getHashSize()	Returns the number of map entries.
Object	getHashValue(Value key)	Returns the value for the specified key.
boolean	hasHashEntry(Value key)	Returns true if the proxy object contains a mapping for the specified key, or else false.
void	putHashEntry(Value key, Value value)	Associates the specified value with the specified key.
default boolean	removeHashEntry(Value key)	Removes the mapping for a given key.

Method Details

getHashSize

long getHashSize()

Returns the number of map entries.

Since:

21.1

hasHashEntry

boolean hasHashEntry(Value key)

Returns true if the proxy object contains a mapping for the specified key, or else false. Every key which returns true for hasHashEntry(Value) must be included in the iterator returned by getHashEntriesIterator() to allow guest language to enumerate map entries.

Since:

21.1

See Also:

• getHashEntriesIterator()

getHashValue

Object getHashValue(Value key)

Returns the value for the specified key.

Throws:

UnsupportedOperationException - if the operation is unsupported

Since:

21.1

putHashEntry

void putHashEntry(Value key,
 Value value)

Associates the specified value with the specified key. If the mapping for the specified key does not exist then a new mapping is defined otherwise, an existing mapping is updated.

Throws:

UnsupportedOperationException - if the operation is unsupported

Since:

21.1

removeHashEntry

default boolean removeHashEntry(Value key)

Removes the mapping for a given key. If the removal of existing mappings is not supported then an UnsupportedOperationException is thrown.

Returns:

true when the mapping was removed, false when the mapping didn't exist.

Throws:

UnsupportedOperationException - if the operation is unsupported

Since:

21.1

getHashEntriesIterator

Object getHashEntriesIterator()

Returns the hash entries iterator. The returned object must be interpreted as an iterator using the semantics of Context.asValue(Object) otherwise an IllegalStateException is thrown. The iterator elements must be interpreted as two elements array using the semantics of Context.asValue(Object).

Examples for valid return values are:

• ProxyIterator
• Iterator, requires host iterable access
• A guest language object representing an iterator

Examples for valid iterator elements are:

• ProxyArray
• List, requires host list access
• Object[2], requires host array access
• Map.Entry, requires host map access
• A guest language object representing an array

Since:

21.1

See Also:

• ProxyIterator

from

static ProxyHashMap from(Map<Object,Object> values)

Creates a proxy hash map backed by a Java Map. The map keys are as Object unboxed. If the set values are host values then they will be unboxed.

Since:

21.1