001/*
002 * SPDX-License-Identifier: Apache-2.0
003 *
004 * Copyright 2024-2026 The Enola <https://enola.dev> Authors
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 *     https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package dev.enola.common;
019
020import static java.util.Objects.requireNonNull;
021
022import com.google.common.reflect.TypeToken;
023
024import java.util.Objects;
025
026public final class MutableObjectWithTypeToken<T> implements ObjectWithTypeToken<T> {
027
028    private final TypeToken<T> typeToken;
029    private T object;
030
031    public MutableObjectWithTypeToken(TypeToken<T> typeToken) {
032        this.typeToken = requireNonNull(typeToken);
033    }
034
035    @Override
036    public TypeToken<T> typeToken() {
037        return typeToken;
038    }
039
040    public void set(ObjectWithTypeToken<?> objectWithTypeToken) {
041        if (!objectWithTypeToken.typeToken().equals(typeToken)) {
042            throw new IllegalArgumentException(
043                    "Cannot set a " + objectWithTypeToken + " into a " + typeToken);
044        }
045        set(objectWithTypeToken, this);
046    }
047
048    @SuppressWarnings("unchecked")
049    private void set(ObjectWithTypeToken<?> from, MutableObjectWithTypeToken<?> into) {
050        var fromWithObject = (ObjectWithTypeToken<Object>) from;
051        var intoWithObject = (MutableObjectWithTypeToken<Object>) into;
052        intoWithObject.setObject(fromWithObject.object());
053    }
054
055    public void setObject(T object) {
056        if (!typeToken.getRawType().isInstance(object)) {
057            throw new IllegalArgumentException(
058                    typeToken.toString() + " expected, but got: " + object.toString());
059        }
060        this.object = requireNonNull(object);
061    }
062
063    @Override
064    public T object() {
065        return object;
066    }
067
068    @Override
069    public boolean equals(Object o) {
070        if (this == o) return true;
071        if (!(o instanceof MutableObjectWithTypeToken<?> that)) return false;
072        return Objects.equals(typeToken, that.typeToken) && Objects.equals(object, that.object);
073    }
074
075    @Override
076    public int hashCode() {
077        return Objects.hash(typeToken, object);
078    }
079
080    @Override
081    public String toString() {
082        return "MutableObjectWithTypeToken{"
083                + "typeToken="
084                + typeToken
085                + ", object="
086                + object
087                + '}';
088    }
089}