Blackboard (plugin-spi 0.3.0 API)

All Known Implementing Classes:

StandardBlackboard
```
public interface Blackboard
```
An entity that stores various properties for an environment

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`<V> Optional<V>`	`find(Key<V> key)`
`<V> V`	`get(Key<V> key)`
`<V> V`	`getOrCreate(Key<V> key, Supplier<? super V> defaultValue)`	Retrieves a value by `key` or from the `default value`.

- Method Detail
  - getOrCreate
```
<V> V getOrCreate(Key<V> key,
                  Supplier<? super V> defaultValue)
```
    Retrieves a value by key or from the default value.
    
    Type Parameters:
    
    V - The value type
    
    Parameters:
    
    key - The key
    
    defaultValue - The default value
    
    Returns:
    
    The value
  - get
```
<V> V get(Key<V> key)
```
    Type Parameters:
    
    V - The value type
    
    Parameters:
    
    key - The key
    
    Returns:
    
    The value
    
    Throws:
    
    IllegalArgumentException - if the key has no corresponding value
  - find
```
<V> Optional<V> find(Key<V> key)
```
    Type Parameters:
    
    V - The value type
    
    Parameters:
    
    key - The key
    
    Returns:
    
    The value or Optional.empty() otherwise