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/**
 * Copyright 2018 Mike Hummel
 *
 * 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 de.mhus.lib.adb;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import de.mhus.lib.basics.MCloseable;
import de.mhus.lib.core.util.Table;
import de.mhus.lib.errors.MException;

/**
 * Represents a collection of results.
 *
 * @author mikehummel
 * @param 
 */
public interface DbCollection extends Iterable, Iterator, MCloseable {

    /**
     * If recycle is on the original container object will be used for every iteration. If it's off
     * then every time a new object will be created. Default is off.
     *
     * Not every implementation supports recycling.
     *
     * @param on
     * @return x
     */
    DbCollection setRecycle(boolean on);

    boolean isRecycle();

    O current() throws MException;

    @SuppressWarnings({"rawtypes", "unchecked"})
    default void addToList(List list) {
        for (O o : this) {
            list.add(o);
        }
    }

    default List toCacheAndClose() {
        List list = new LinkedList();
        addToList(list);
        close();
        return list;
    }

    default O[] toArrayAndClose(O[] dummy) {
        List list = toCacheAndClose();
        return list.toArray(dummy);
    }

    /**
     * Transfer Objects to a table view.
     *
     * @param maxSize More the zero, zero or less will disable the parameter
     * @return x
     */
    Table toTableAndClose(int maxSize);

    public default O getNextAndClose() {
        try {
            return hasNext() ? next() : null;
        } finally {
            close();
        }
    }

    default boolean skip(int cnt) { // TODO optimize, do not fully load objects
        for (int i = 0; i < cnt && hasNext(); i++) next();
        return hasNext();
    }
}