Struct JSet 

pub struct JSet<'local>(/* private fields */);

A java.util.Set reference, tied to a JNI local reference frame.

See the JObject documentation for more information about object references, how to cast them, and local reference frame lifetimes.

Implementations

impl<'local> JSet<'local>

pub unsafe fn from_raw<'env_inner>( env: &Env<'env_inner>, raw: jobject, ) -> JSet<'env_inner>

Creates a JSet that wraps the given raw jobject

Safety

• raw must be a valid raw JNI local reference (or null).
• raw must be an instance of the correct Java class.
• There must not be any other owning Reference wrapper for the same reference.
• The local reference must belong to the current thread and not outlive the JNI stack frame associated with the Env 'local lifetime.

pub const fn null() -> JSet<'static>

Creates a new null reference.

Null references are always valid and do not belong to a local reference frame. Therefore, the returned JSet always has the 'static lifetime.

pub fn into_raw(self) -> jobject

Unwrap to the raw jni type.

pub fn cast_local<'any_local>( env: &mut Env<'_>, obj: impl Reference + Into<JObject<'any_local>> + AsRef<JObject<'any_local>>, ) -> Result<JSet<'any_local>>

Cast a local reference to a JSet

This will do a runtime (IsInstanceOf) check that the object is an instance of the correct class.

Also see these other options for casting local or global references to a JSet:

• Env::as_cast
• Env::new_cast_local_ref
• Env::cast_local
• Env::new_cast_global_ref
• Env::cast_global

Errors

Returns Error::WrongObjectType if the IsInstanceOf check fails.

impl<'local> JSet<'local>

pub fn as_collection(&self) -> Cast<'local, '_, JCollection<'local>>

Casts this JSet to a ::jni::objects::JCollection

This does not require a runtime type check since any JSet is also a ::jni::objects::JCollection

impl<'local> JSet<'local>

pub fn add<'any_local>( &self, env: &mut Env<'_>, element: impl AsRef<JObject<'any_local>>, ) -> Result<bool>

Adds the given element to this set if it is not already present

Returns true if the element was added, false if it was already present.

Throws

• UnsupportedOperationException - if the add operation is not supported
• ClassCastException - if the element type isn’t compatible with the set
• NullPointerException - if the given element is null and the set does not allow null values
• IllegalArgumentException - if the element has a property that prevents it from being added to this set

pub fn remove<'any_local>( &self, env: &mut Env<'_>, element: impl AsRef<JObject<'any_local>>, ) -> Result<bool>

Removes the given element from this set if it is present

Returns true if the element was removed.

Throws

• UnsupportedOperationException - if the remove operation is not supported
• ClassCastException - if the element type isn’t compatible with the set
• NullPointerException - if the given element is null and the set does not allow null values

pub fn clear(&self, env: &mut Env<'_>) -> Result<()>

Removes all of the elements from this set.

Throws

• UnsupportedOperationException - if the clear operation is not supported

pub fn contains(&self, env: &mut Env<'_>, element: &JObject<'_>) -> Result<bool>

Checks if the given element is present in this set.

Returns true if the element is present, false otherwise.

Throws

• ClassCastException - if the element type isn’t compatible with the set
• NullPointerException - if the given element is null and the set does not allow null values

pub fn size(&self, env: &mut Env<'_>) -> Result<i32>

Returns the number of elements in this set.

pub fn is_empty(&self, env: &mut Env<'_>) -> Result<bool>

Returns true if this set contains no elements.

pub fn iterator<'env_local>( &self, env: &mut Env<'env_local>, ) -> Result<JIterator<'env_local>>

Returns an iterator (java.util.Iterator) over the elements in this set.

Methods from Deref<Target = JObject<'local>>

pub fn as_raw(&self) -> jobject

Returns the raw JNI pointer.

Trait Implementations

impl<'local> AsRef<JCollection<'local>> for JSet<'local>

fn as_ref(&self) -> &JCollection<'local>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'local> AsRef<JObject<'local>> for JSet<'local>

fn as_ref(&self) -> &JObject<'local>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'local> AsRef<JSet<'local>> for JSet<'local>

fn as_ref(&self) -> &JSet<'local>

Converts this type into a shared reference of the (usually inferred) input type.

impl<'local> Debug for JSet<'local>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'local> Default for JSet<'local>

fn default() -> JSet<'local>

Returns the “default value” for a type.

impl<'local> Deref for JSet<'local>

type Target = JObject<'local>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'local> From<JSet<'local>> for JCollection<'local>

fn from(value: JSet<'local>) -> JCollection<'local>

Converts to this type from the input type.

impl<'local> From<JSet<'local>> for JObject<'local>

fn from(other: JSet<'local>) -> JObject<'local>

Converts to this type from the input type.

impl<'local> Reference for JSet<'local>

type Kind<'env> = JSet<'env>

The generic associated Self::Kind type corresponds to the underlying class type (such as JObject or JString), parameterized by the lifetime that indicates whether the type holds a global reference ('static) or a local reference that’s tied to a JNI stack frame.

type GlobalKind = JSet<'static>

The associated GlobalKind type should be equivalent to Kind<'static>, with the additional bound that ensures the type is Send + Sync

fn as_raw(&self) -> jobject

Returns the underlying, raw crate::sys::jobject reference.

fn class_name() -> Cow<'static, JNIStr>

The fully qualified class name of the Java class represented by this reference.

fn lookup_class<'caller>( env: &Env<'_>, loader_context: &LoaderContext<'_, '_>, ) -> Result<impl Deref<Target = Global<JClass<'static>>> + 'caller>

Looks up a global reference to the JClass associated with this reference.

unsafe fn kind_from_raw<'env>(local_ref: jobject) -> Self::Kind<'env>

Returns a new reference type based on Self::Kind for the given reference that is tied to the specified lifetime.

unsafe fn global_kind_from_raw(global_ref: jobject) -> Self::GlobalKind

Returns a ('static) reference type based on Self::GlobalKind for the given global_ref.

fn is_null(&self) -> bool

Returns true if this is a null object reference

fn null<'any>() -> Self::Kind<'any>

Returns null reference based on Self::Kind