OptionalConstructorParam (Stardog-9.0.0 API)

java.lang.Object
- com.complexible.common.inject.OptionalConstructorParam<T>

All Implemented Interfaces:

java.util.function.Supplier<T>
```
public final class OptionalConstructorParam<T>
extends java.lang.Object
implements java.util.function.Supplier<T>
```
Workaround for optional constructor parameters with Guice. Modeled after the Guava Optional class, but you cannot create your own Optional because the constructor is private, so just adopting the look and feel of it.

Unfortunately, this does not support optional bindings which use @Named; that annotation on the value in the constructor, eg:

public Foo(@Named("bar") OptionalConstructorParam<MyObject> theParam)

Because the @Inject is inside OptionalConstructorParam and that's where the injection actually takes place, the @Named annotation is essentially ignored. If you could place @Named inside this class, with a parameterized value for the name, that would work as expected, but annotation values have to be consts, so there's no way to pass in the name to the annotation. So if you want to use @Named w/ an optional constructor parameter, you basically have to duplicate the Guice part of this class locally and use the @Named annotation explicitly.

Since:

0.6.5

Version:

4.0

Author:

Michael Grove

See Also:

Guice Frequently Asked Questions

Constructor Summary

Constructors
Constructor Description

OptionalConstructorParam()

OptionalConstructorParam(T theValue)

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`java.util.Optional<T>`	`asOptional()`
`static <T> OptionalConstructorParam<T>`	`create(T theValue)`
`boolean`	`equals(java.lang.Object o)`
`T`	`get()`
`int`	`hashCode()`
`boolean`	`isPresent()`
`T`	`or(java.util.function.Supplier<? extends T> theDefault)`
`T`	`or(T theDefault)`
`T`	`orNull()`
`java.lang.String`	`toString()`

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

Constructor Detail

OptionalConstructorParam

@Inject
public OptionalConstructorParam()

OptionalConstructorParam

public OptionalConstructorParam(T theValue)

Method Detail

get
```
public T get()
```
Specified by:

get in interface java.util.function.Supplier<T>

or
```
public T or(T theDefault)
```

or

public T or(java.util.function.Supplier<? extends T> theDefault)

orNull
```
public T orNull()
```

asOptional

public java.util.Optional<T> asOptional()

equals

public boolean equals(java.lang.Object o)

Overrides:: equals in class java.lang.Object

hashCode
```
public int hashCode()
```
Overrides:

hashCode in class java.lang.Object

toString
```
public java.lang.String toString()
```
Overrides:

toString in class java.lang.Object

isPresent
```
public boolean isPresent()
```

create

public static <T> OptionalConstructorParam<T> create(T theValue)