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ixjava developed by David Karnok

There is a newer version: 1.0.0

/*
 * Copyright 2011-2016 David Karnok
 *
 * 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 ix;

import java.util.*;

final class IxBufferSkip extends IxSource> {

    final int size;

    final int skip;

    IxBufferSkip(Iterable source, int size, int skip) {
        super(source);
        this.size = size;
        this.skip = skip;
    }

    @Override
    public Iterator> iterator() {
        return new BufferSkipIterator(source.iterator(), size, skip);
    }

    static final class BufferSkipIterator extends IxSourceIterator> {
        final int size;

        final int skip;

        boolean once;

        BufferSkipIterator(Iterator it, int size, int skip) {
            super(it);
            this.size = size;
            this.skip = skip;
        }

        @Override
        protected boolean moveNext() {
            Iterator it = this.it;

            int s = size;

            if (once) {
                int k = skip - s;
                while (k != 0 && it.hasNext()) {
                    it.next();
                    k--;
                }

            } else {
                once = true;
            }

            List list = new ArrayList();

            while (s != 0 && it.hasNext()) {
                list.add(it.next());
                s--;
            }


            if (list.isEmpty()) {
                done = true;
                return false;
            }
            value = list;
            hasValue = true;
            if (s != 0) {
                done = true;
            }
            return true;
        }


    }
}