Package org.glassfish.jersey.internal.util.collection

Class Values

java.lang.Object

org.glassfish.jersey.internal.util.collection.Values

public final class Values
extends java.lang.Object

A collection of Value provider factory & utility methods.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	Values.EagerValue<T>
private static class	Values.ExceptionValue<T,E extends java.lang.Throwable>
private static class	Values.InstanceUnsafeValue<T,E extends java.lang.Throwable>
private static class	Values.InstanceValue<T>
private static class	Values.LazyUnsafeValueImpl<T,E extends java.lang.Throwable>
private static class	Values.LazyValueImpl<T>

Field Summary

Fields

Modifier and Type	Field	Description
private static LazyValue	EMPTY
private static LazyUnsafeValue	EMPTY_UNSAFE

Constructor Summary

Constructors

Modifier	Constructor	Description
private	Values()

Method Summary

Modifier and Type	Method	Description
static <T> Value<T>	eager(Value<T> delegate)	Get a new eagerly initialized value provider.
static <T> Value<T>	empty()	Get an empty value provider whose get() method always returns null.
static <T,E extends java.lang.Throwable> UnsafeValue<T,E>	emptyUnsafe()	Get an empty value provider whose get() method always returns null.
static <T,E extends java.lang.Throwable> LazyUnsafeValue<T,E>	lazy(UnsafeValue<T,E> delegate)	Get a new lazily initialized unsafe value provider.
static <T> LazyValue<T>	lazy(Value<T> delegate)	Get a new lazily initialized value provider.
static <T> Value<T>	of(T value)	Get a new constant value provider whose get() method always returns the instance supplied to the value parameter.
static <T,E extends java.lang.Throwable> UnsafeValue<T,E>	throwing(E throwable)	Get a new "throwing" unsafe value provider whose get() method always throws the exception supplied to the throwable parameter.
static <T,E extends java.lang.Throwable> UnsafeValue<T,E>	unsafe(T value)	Get a new constant value provider whose get() method always returns the instance supplied to the value parameter.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

EMPTY

private static final LazyValue EMPTY

EMPTY_UNSAFE

private static final LazyUnsafeValue EMPTY_UNSAFE

Constructor Detail

Values

private Values()

Method Detail

empty

public static <T> Value<T> empty()

Get an empty value provider whose get() method always returns null.

Type Parameters:

T - value type.

Returns:

empty value provider.

emptyUnsafe

public static <T,E extends java.lang.Throwable> UnsafeValue<T,E> emptyUnsafe()

Get an empty value provider whose get() method always returns null.

Type Parameters:

T - value type.

Returns:

empty unsafe value provider.

of

public static <T> Value<T> of(T value)

Get a new constant value provider whose get() method always returns the instance supplied to the value parameter.

In case the supplied value constant is null, an empty value provider is returned.

Type Parameters:

T - value type.

Parameters:

value - value instance to be provided.

Returns:

constant value provider.

unsafe

public static <T,E extends java.lang.Throwable> UnsafeValue<T,E> unsafe(T value)

Get a new constant value provider whose get() method always returns the instance supplied to the value parameter.

In case the supplied value constant is null, an empty value provider is returned.

Type Parameters:

T - value type.

Parameters:

value - value instance to be provided.

Returns:

constant value provider.

throwing

public static <T,E extends java.lang.Throwable> UnsafeValue<T,E> throwing(E throwable)

Get a new "throwing" unsafe value provider whose get() method always throws the exception supplied to the throwable parameter.

In case the supplied throwable is null, an NullPointerException is thrown.

Type Parameters:

T - value type.

E - exception type.

Parameters:

throwable - throwable instance to be thrown.

Returns:

"throwing" unsafe value provider.

Throws:

java.lang.NullPointerException - in case the supplied throwable instance is null.

lazy

public static <T> LazyValue<T> lazy(Value<T> delegate)

Get a new lazily initialized value provider.

The value returned by its get() method is lazily retrieved during a first call to the method from the supplied delegate value provider and is then cached for a subsequent retrieval.

The implementation of the returned lazy value provider is thread-safe and is guaranteed to invoke the get() method on the supplied delegate value provider instance at most once.

If the supplied value provider is null, an empty value provider is returned.

Type Parameters:

T - value type.

Parameters:

delegate - value provider delegate that will be used to lazily initialize the value provider.

Returns:

lazily initialized value provider.

eager

public static <T> Value<T> eager(Value<T> delegate)

Get a new eagerly initialized value provider.

The value returned by its get() method is eagerly computed from the supplied delegate value provider and is then stored in a final field for a subsequent retrieval.

The implementation of the returned eager value provider is thread-safe and is guaranteed to invoke the get() method on the supplied delegate value provider instance once and only once.

If the supplied value provider is null, an empty value provider is returned.

Type Parameters:

T - value type.

Parameters:

delegate - value provider delegate that will be used to eagerly initialize the value provider.

Returns:

eagerly initialized, constant value provider.

lazy

public static <T,E extends java.lang.Throwable> LazyUnsafeValue<T,E> lazy(UnsafeValue<T,E> delegate)

Get a new lazily initialized unsafe value provider.

The value returned by its get() method is lazily retrieved during a first call to the method from the supplied delegate value provider and is then cached for a subsequent retrieval.

In case the call to underlying delegate.get() throws a throwable, the throwable is cached and thrown on all subsequent retrievals.

The implementation of the returned lazy value provider is thread-safe and is guaranteed to invoke the get() method on the supplied delegate value provider instance at most once.

If the supplied value provider is null, an empty value provider is returned.

Type Parameters:

T - value type.

Parameters:

delegate - value provider delegate that will be used to lazily initialize the value provider.

Returns:

lazily initialized value provider.