com.jdonee.framework.util.pagehelper.Page.java Source code

Introduction

Here is the source code for com.jdonee.framework.util.pagehelper.Page.java

Source

/*
   The MIT License (MIT)
    
   Copyright (c) 2014 abel533@gmail.com
    
   Permission is hereby granted, free of charge, to any person obtaining a copy
   of this software and associated documentation files (the "Software"), to deal
   in the Software without restriction, including without limitation the rights
   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   copies of the Software, and to permit persons to whom the Software is
   furnished to do so, subject to the following conditions:
    
   The above copyright notice and this permission notice shall be included in
   all copies or substantial portions of the Software.
    
   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   THE SOFTWARE.
 */

package com.jdonee.framework.util.pagehelper;

import java.util.ArrayList;
import java.util.List;

import org.apache.ibatis.session.RowBounds;

/**
 * Mybatis - 
 *
 * @author liuzh/abel533/isea533
 * @version 3.3.0
 *          ? : http://git.oschina.net/free/Mybatis_PageHelper
 */
public class Page<E> extends ArrayList<E> {
    /**
     * ?count
     */
    private static final int NO_SQL_COUNT = -1;

    public static final String PAGE_SIZE = "10";

    public static final String PAGE_NUM = "1";

    /**
     * count
     */
    private static final int SQL_COUNT = 0;

    private int pageNum;
    private int pageSize;
    private int startRow;
    private int endRow;
    private long total;
    private int pages;

    public Page() {
        super();
    }

    public Page(int pageNum, int pageSize) {
        this(pageNum, pageSize, SQL_COUNT);
    }

    public Page(int pageNum, int pageSize, boolean count) {
        this(pageNum, pageSize, count ? Page.SQL_COUNT : Page.NO_SQL_COUNT);
    }

    public Page(int pageNum, int pageSize, int total) {
        super(pageSize > -1 ? pageSize : 0);
        // ???????
        if (PageHelper.isReasonable() && pageNum <= 0) {
            pageNum = 1;
        }
        this.pageNum = pageNum;
        this.pageSize = pageSize;
        this.total = total;
        calculateStartAndEndRow();
    }

    public Page(RowBounds rowBounds, boolean count) {
        this(rowBounds, count ? Page.SQL_COUNT : Page.NO_SQL_COUNT);
    }

    public Page(RowBounds rowBounds, int total) {
        super(rowBounds.getLimit() > -1 ? rowBounds.getLimit() : 0);
        this.pageSize = rowBounds.getLimit();
        this.startRow = rowBounds.getOffset();
        // RowBounds??countcount,?SQL_COUNT
        this.total = total;
        this.endRow = this.startRow + this.pageSize;
    }

    public List<E> getResult() {
        return this;
    }

    public void setEndRow(int endRow) {
        this.endRow = endRow;
    }

    public void setPages(int pages) {
        this.pages = pages;
    }

    public int getPages() {
        return pages;
    }

    public int getEndRow() {
        return endRow;
    }

    public int getPageNum() {
        return pageNum;
    }

    public void setPageNum(int pageNum) {
        // ???????
        this.pageNum = (PageHelper.isReasonable() && pageNum <= 0) ? 1 : pageNum;
    }

    public int getPageSize() {
        return pageSize;
    }

    public void setPageSize(int pageSize) {
        this.pageSize = pageSize;
    }

    public int getStartRow() {
        return startRow;
    }

    public long getTotal() {
        return total;
    }

    public void setTotal(long total) {
        this.total = total;
        if (pageSize > 0) {
            pages = (int) (total / pageSize + ((total % pageSize == 0) ? 0 : 1));
        } else {
            pages = 0;
        }
        // ???????
        if (PageHelper.isReasonable() && pageNum > pages) {
            pageNum = pages;
            calculateStartAndEndRow();
        }
    }

    /**
     * ?
     */
    private void calculateStartAndEndRow() {
        this.startRow = this.pageNum > 0 ? (this.pageNum - 1) * this.pageSize : 0;
        this.endRow = this.startRow + this.pageSize * (this.pageNum > 0 ? 1 : 0);
    }

    public boolean isCount() {
        return this.total > NO_SQL_COUNT;
    }

    @Override
    public String toString() {
        return "Page{" + "pageNum=" + pageNum + ", pageSize=" + pageSize + ", startRow=" + startRow + ", endRow="
                + endRow + ", total=" + total + ", pages=" + pages + '}';
    }
}