java - 分页类

pager.java

package com.jspnews.util;

import java.io.Serializable;
import java.util.List;

/**
 * 
 * <b> 分页通用类 </b>
 * 
 * @author kangxu
 * @param <T>
 * 
 */
public class Pager {

	/**
	 * 
	 */
	private static final long serialVersionUID = 4542617637761955078L;

	/**
	 * currentPage 当前页
	 */
	private int currentPage = 1;
	/**
	 * pageSize 每页大小
	 */
	private int pageSize = 10;
	/**
	 * pageTotal 总页数
	 */
	private int pageTotal;
	/**
	 * recordTotal 总条数
	 */
	private int recordTotal = 0;
	/**
	 * previousPage 前一页
	 */
	private int previousPage;
	/**
	 * nextPage 下一页
	 */
	private int nextPage;
	/**
	 * firstPage 第一页
	 */
	private int firstPage = 1;
	/**
	 * lastPage 最后一页
	 */
	private int lastPage;

	/**
	 * 拼接url
	 */
	private String url = "?p=";

	public String getUrl() {
		return url;
	}

	public void setUrl(String url) {
		this.url = url;
	}

	// 以下set方式是需要赋值的
	/**
	 * 设置当前页 <br>
	 * 
	 * @author kangxu
	 * 
	 * @param currentPage
	 */
	public void setCurrentPage(int currentPage) {
		this.currentPage = currentPage;
	}

	/**
	 * 设置每页大小,也可以不用赋值,默认大小为10条 <br>
	 * 
	 * @author kangxu
	 * 
	 * @param pageSize
	 */
	public void setPageSize(int pageSize) {
		this.pageSize = pageSize;
	}

	/**
	 * 设置总条数,默认为0 <br>
	 * 
	 * @author kangxu
	 * 
	 * @param recordTotal
	 */
	public void setRecordTotal(int recordTotal) {
		this.recordTotal = recordTotal;
		otherAttr();
	}

	/**
	 * 设置其他参数
	 * 
	 * @author kangxu
	 * 
	 */
	public void otherAttr() {
		// 总页数
		this.pageTotal = this.recordTotal % this.pageSize > 0 ? this.recordTotal / this.pageSize + 1
				: this.recordTotal / this.pageSize;
		// 第一页
		this.firstPage = 1;
		// 最后一页
		this.lastPage = this.pageTotal;
		// 前一页
		if (this.currentPage > 1) {
			this.previousPage = this.currentPage - 1;
		} else {
			this.previousPage = this.firstPage;
		}
		// 下一页
		if (this.currentPage < this.lastPage) {
			this.nextPage = this.currentPage + 1;
		} else {
			this.nextPage = this.lastPage;
		}
	}

	public int getCurrentPage() {
		return currentPage;
	}

	public int getPageSize() {
		return pageSize;
	}

	public int getPageTotal() {
		return pageTotal;
	}

	public int getRecordTotal() {
		return recordTotal;
	}

	public int getPreviousPage() {
		return previousPage;
	}

	public int getNextPage() {
		return nextPage;
	}

	public int getFirstPage() {
		return firstPage;
	}

	public int getLastPage() {
		return lastPage;
	}

	@Override
	public String toString() {
		return "Pager [currentPage=" + currentPage + ", pageSize=" + pageSize + ", pageTotal=" + pageTotal
				+ ", recordTotal=" + recordTotal + ", previousPage=" + previousPage + ", nextPage=" + nextPage
				+ ", firstPage=" + firstPage + ", lastPage=" + lastPage + ", url=" + url + "]";
	}

}

　　

test

package com.jspnews.test;

import com.jspnews.util.Pager;

public class TestPager {
	
	public static void main(String[] args) {
		Pager pager = new Pager();
        
		pager.setCurrentPage(-1);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
		
		pager.setCurrentPage(0);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
		
        pager.setCurrentPage(1);
        pager.setPageSize(4);
        pager.setRecordTotal(15);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(2);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(3);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(4);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(5);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(6);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
        
        pager.setCurrentPage(7);
        pager.setPageSize(4);
        pager.setRecordTotal(21);
        System.out.println(pager.getPreviousPage() + "," + pager.getNextPage());
	}
}

　　

result

1,0
1,1
1,2
1,3
2,4
3,5
4,6
5,6
6,6