/*
 * JEF - Copyright 2009-2010 Jiyi (mr.jiyi@gmail.com)
 *
 * 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 jef.common.wrapper;

import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

import jef.tools.PageInfo;
import jef.tools.PageLimit;

/**
 * 对象分页器，将List对象分页
 * 
 * @author Administrator
 *
 * @param <T>
 */
public class Paginator<T> implements Iterable<List<T>> {
	PageInfo p;
	List<T> data;

	public Iterator<List<T>> iterator() {
		return new Iterator<List<T>>() {
			public boolean hasNext() {
				return p.hasNext();
			}

			public List<T> next() {
				PageLimit r = p.getCurrentRecordRange();
				return data.subList(r.getStartAsInt(), r.getEndAsInt());
			}

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

	public List<T> get(int pageNum) {
		p.setCurPage(pageNum);
		PageLimit r = p.getCurrentRecordRange();
		return data.subList(r.getStartAsInt(), r.getEndAsInt());
	}

	public Paginator(T[] data, int rowsPerPage) {
		this.data = Arrays.asList(data);
		this.p = new PageInfo(data.length, rowsPerPage);
	}

	public Paginator(List<T> data, int rowsPerPage) {
		this.data = data;
		this.p = new PageInfo(data.size(), rowsPerPage);
	}

	public int getTotal() {
		return (int) p.getTotal();
	}

	public int getCurrentPage() {
		return p.getCurrentPage();
	}

	public int getTotalPage() {
		return p.getTotalPage();
	}

	public void setPage(int page) {
		p.setCurPage(page);
	}

	public void nextPage() {
		p.gotoNext();
	}

	public void prevPage() {
		p.gotoPrev();
	}
}