/*
 * Copyright (c) 2015-2018 Dzikoysk
 *
 * 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.
 */

package org.panda_lang.panda.utilities.commons.collection;

import org.jetbrains.annotations.*;

import java.util.*;

public class ReverseIterator<T> implements Iterator<T>, Iterable<T> {

    private final List<T> list;
    private int index;

    public ReverseIterator(List<T> list) {
        this.list = list;
        this.index = list.size() - 1;
    }

    @Override
    public @NotNull Iterator<T> iterator() {
        return this;
    }

    @Override
    public boolean hasNext() {
        return index >= 0;
    }

    @Override
    public @Nullable T next() {
        return index - 1 > -1 ? list.get(index--) : null;
    }

    @Override
    public void remove() {
        throw new UnsupportedOperationException();
    }

}
/*
 * Copyright (c) 2015-2018 Dzikoysk
 *
 * 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.
 */

package org.panda_lang.panda.utilities.commons.collection;

import org.jetbrains.annotations.*;

import java.util.*;

public class ReverseIterator<T> implements Iterator<T>, Iterable<T> {

    private final List<T> list;
    private int index;

    public ReverseIterator(List<T> list) {
        this.list = list;
        this.index = list.size() - 1;
    }

    @Override
    public @NotNull Iterator<T> iterator() {
        return this;
    }

    @Override
    public boolean hasNext() {
        return index > 0;
    }

    @Override
    public @Nullable T next() {
        return index - 1 > -1 ? list.get(index--) : null;
    }

    @Override
    public void remove() {
        throw new UnsupportedOperationException();
    }

}
Fix RevereIterator#hasNext