package com.zhuinden.simplestackdemoexamplemvp.util.optional;
/*
* Copyright (C) 2011 The Guava Authors
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
import android.support.annotation.Nullable;
import com.zhuinden.simplestackdemoexamplemvp.util.Preconditions;
import java.util.Collections;
import java.util.Set;
/**
* Implementation of an {@link Optional} containing a reference.
*/
final class Present<T>
extends Optional<T> {
private final T reference;
Present(T reference) {
this.reference = reference;
}
@Override
public boolean isPresent() {
return true;
}
@Override
public T get() {
return reference;
}
@Override
public T or(T defaultValue) {
Preconditions.checkNotNull(defaultValue, "use Optional.orNull() instead of Optional.or(null)");
return reference;
}
@Override
public Optional<T> or(Optional<? extends T> secondChoice) {
Preconditions.checkNotNull(secondChoice);
return this;
}
@Override
public T orNull() {
return reference;
}
@Override
public Set<T> asSet() {
return Collections.singleton(reference);
}
@Override
public boolean equals(@Nullable Object object) {
if(object instanceof Present) {
Present<?> other = (Present<?>) object;
return reference.equals(other.reference);
}
return false;
}
@Override
public int hashCode() {
return 0x598df91c + reference.hashCode();
}
@Override
public String toString() {
return "Optional.of(" + reference + ")";
}
private static final long serialVersionUID = 0;
}