tech.jhipster.web.util.PageUtil Maven / Gradle / Ivy
/*
* Copyright 2016-2023 the original author or authors from the JHipster project.
*
* This file is part of the JHipster project, see https://www.jhipster.tech/
* for more information.
*
* 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 tech.jhipster.web.util;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Pageable;
import java.util.ArrayList;
import java.util.List;
/**
* Utility class for creating a Page object.
*/
public interface PageUtil {
/**
* Create a {@link org.springframework.data.domain.Page} from a {@link java.util.List} of objects
*
* @param list list of objects
* @param pageable pagination information.
* @param type of object
* @return page containing objects, and attributes set according to pageable
* @throws java.lang.IllegalArgumentException - if list is null
*/
static Page createPageFromList(List list, Pageable pageable) {
if (list == null) {
throw new IllegalArgumentException("To create a Page, the list mustn't be null!");
}
int startOfPage = pageable.getPageNumber() * pageable.getPageSize();
if (startOfPage > list.size()) {
return new PageImpl<>(new ArrayList<>(), pageable, 0);
}
int endOfPage = Math.min(startOfPage + pageable.getPageSize(), list.size());
return new PageImpl<>(list.subList(startOfPage, endOfPage), pageable, list.size());
}
}