001/*
002 * (C) Copyright 2014-2017 Nuxeo (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     bdelbosc
018 */
019package org.nuxeo.ecm.core.api;
020
021import java.util.Collections;
022import java.util.List;
023
024/**
025 * @since 8.4
026 */
027public class ScrollResultImpl<T> implements ScrollResult<T> {
028
029    protected static final ScrollResult<?> EMPTY_RESULT = new ScrollResultImpl<>("empty", Collections.emptyList());
030
031    protected final String scrollId;
032
033    protected final List<T> results;
034
035    @SuppressWarnings("unchecked")
036    public static <O> ScrollResult<O> emptyResult() {
037        return (ScrollResult<O>) EMPTY_RESULT;
038    }
039
040    public ScrollResultImpl(String scrollId, List<T> results) {
041        this.scrollId = scrollId;
042        this.results = Collections.unmodifiableList(results);
043    }
044
045    @Override
046    public String getScrollId() {
047        return scrollId;
048    }
049
050    @Override
051    public boolean hasResults() {
052        return results != null && !results.isEmpty();
053    }
054
055    @Override
056    @SuppressWarnings("unchecked")
057    public List<T> getResults() {
058        return results;
059    }
060
061}