hu.akarnokd.reactive4java.util

Class SingleOption<T>

java.lang.Object

hu.akarnokd.reactive4java.util.SingleOption<T>

Type Parameters:

T - the contained value type

public final class SingleOption<T>
extends java.lang.Object

Container that may contain a single value or an exception, but not both.

The caller may add a single value or exception to this container. Any subsequent add attempt results in IllegalStateException.

The caller may retrieve the value or exception from this container, which is then removed from the container; the caller may add a new value or exception. If the caller attempts to remove a value or exception after a value, it will result in IllegalStateException.

The class is not thread safe.

Since:

0.97

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.Throwable	error The stored exception.
protected boolean	hasContent Indicator for having a value or error.
protected T	value The contained value.

Constructor Summary

Constructors

Constructor and Description
SingleOption()

Method Summary

Modifier and Type	Method and Description
void	add(T value) Add a new value to the container.
void	addError(java.lang.Throwable ex) Add a new error to the container.
void	addOption(Option<? extends T> o) Add a new optional value to the container.
protected void	ensureEmpty() Throws an IllegalStateException if the container is full.
protected void	ensureFull() Throws an IllegalStateException if the container is empty.
boolean	hasError()
boolean	isEmpty()
Option<T>	option()
T	take() Takes the current value or throws a RuntimeException if there is an error instead.
java.lang.Throwable	takeError() Takes just the exception from this container.

Methods inherited from class java.lang.Object

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

Field Detail

hasContent

protected boolean hasContent

Indicator for having a value or error.

value

protected T value

The contained value.

error

protected java.lang.Throwable error

The stored exception.

Constructor Detail

SingleOption

public SingleOption()

Method Detail

add

public void add(T value)

Add a new value to the container. The container must be empty.

Parameters:

value - the value to add

addError

public void addError(@Nonnull
                     java.lang.Throwable ex)

Add a new error to the container. The container must be empty.

Parameters:

ex - the exception to add

isEmpty

public boolean isEmpty()

Returns:

test if the container is empty

ensureEmpty

protected void ensureEmpty()

Throws an IllegalStateException if the container is full.

ensureFull

protected void ensureFull()

Throws an IllegalStateException if the container is empty.

take

public T take()

Takes the current value or throws a RuntimeException if there is an error instead.

The container must be full, and gets empty after the call.

Returns:

the value contained

takeError

@Nonnull
public java.lang.Throwable takeError()

Takes just the exception from this container. The container becomes empty after the call. If the container doesn't hold an exception, an IllegalStateException is thrown.

Returns:

the exception

hasError

public boolean hasError()

Returns:

check if there is an error in this container

option

@Nonnull
public Option<T> option()

Returns:

Consumes the content of this container in a form of an option instance. The container becomes empty after it.

addOption

public void addOption(@Nonnull
                      Option<? extends T> o)

Add a new optional value to the container. The container must be empty. Throws IllegalArgumentException if o is None.

Parameters:

o - the option to add