public boolean toBooleanOrElseGet(final @NotNull BooleanSupplier supplier) {
    switch (this) {
      case TRUE: return true;
      case FALSE: return false;
      default: return supplier.getAsBoolean();
    }
  }
Converts this tri-state back into a {@code boolean}.

<p>As the {@link #NOT_SET} state cannot be represented by the boolean type, this
method maps the {@link #NOT_SET} state to the suppliers result.
This method may hence also be viewed as an equivalent to {@link
java.util.Optional#orElseGet(java.util.function.Supplier)}.</p>

@param supplier the supplier that will be executed to produce the value that should be returned if this tri-state is {@link #NOT_SET}.
@return the boolean representing the tri-state or the result of the passed supplier if this state is {@link #NOT_SET}.
@since 4.10.0
api/src/main/java/net/kyori/adventure/util/TriState.java