分页抄自ajax-solr-master，不懂先记下

package com.risejoin.yunfang.util;

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

public class Page {
	private int currentPage = 1;// 当前页数

	public int totalPages = 0;// 总页数

	private int pageSize = 0;// 每页显示数

	private int totalRows = 0;// 总数据数

	private int startNum = 0;// 开始记录
	
	private int endNum = 0;

	private int nextPage = 0;// 下一页

	private int previousPage = 0;// 上一页

	private boolean hasNextPage = false;// 是否有下一页

	private boolean hasPreviousPage = false;// 是否有前一页
	
	private List<String> pageNum;

	public Page(int pageSize, int currentPage, int totalRows) {

		this.pageSize = pageSize;
		this.currentPage = currentPage;
		this.totalRows = totalRows;

		if ((totalRows % pageSize) == 0) {
			totalPages = totalRows / pageSize;
		} else {
			totalPages = totalRows / pageSize + 1;
		}

		if (currentPage >= totalPages) {
			hasNextPage = false;
			currentPage = totalPages;
		} else {
			hasNextPage = true;
		}

		if (currentPage <= 1) {
			hasPreviousPage = false;
			currentPage = 1;
		} else {
			hasPreviousPage = true;
		}

		startNum = (currentPage - 1) * pageSize;
		endNum = startNum + pageSize;

		nextPage = currentPage + 1;

		if (nextPage >= totalPages) {
			nextPage = totalPages;
		}

		previousPage = currentPage - 1;

		if (previousPage <= 1) {
			previousPage = 1;
		}
		
		int inner = 1;
		int outer = 0;
		int cur = this.currentPage; 
		int total= totalPages;
		int from = cur - inner;
		int to = cur + inner;
		
		List<Integer> list = new ArrayList<Integer>();
		
		if(to > total){
			from = Math.max(0, from - (to - total));
			to = total;
		}
		
		if(from < 1){
		      to = Math.min(total, to + (1 - from));
		      from = 1;
		}
		list.add(1);
		if(total<=1){
			list.remove((Integer)1);
		}
	    for (int i = 2; i <= Math.min(1 + outer, from - 1); i++) {
	    	list.add(i);
	    }
	    if (1 + outer == from - 2) {
	    	list.add(from - 1);
	    }
	    
	    for (int i = Math.max(2, from); i <= Math.min(to, total - 1); i++) {
	    	list.add(i);
	    }
	    
	    if (total - outer == to + 2) {
	    	list.add(to + 1);
	    }
	    
	    for (int i = Math.max(total - outer, to + 1); i < total; i++) {
	    	list.add(i);
	    }
	    if (total > 1) {
	    	list.add(total);
	    }
	    
	    List<String> pageNum = new ArrayList<String>();
	    Integer prev = null;
	    for (int i = 0, l = list.size(); i < l; i++) {
	        if (prev!=null && list.get(i) > prev + 1) pageNum.add("...");
	        pageNum.add(String.valueOf(list.get(i)));
	        prev = list.get(i);
	    }
	    this.pageNum = pageNum;
	}

	
	public List<String> getPageNum() {
		return pageNum;
	}


	public boolean isHasNextPage() {

		return hasNextPage;

	}

	public boolean isHasPreviousPage() {

		return hasPreviousPage;

	}

	/**
	 * @return the nextPage
	 */
	public int getNextPage() {
		return nextPage;
	}

	/**
	 * @param nextPage
	 *            the nextPage to set
	 */
	public void setNextPage(int nextPage) {
		this.nextPage = nextPage;
	}

	/**
	 * @return the previousPage
	 */
	public int getPreviousPage() {
		return previousPage;
	}

	/**
	 * @param previousPage
	 *            the previousPage to set
	 */
	public void setPreviousPage(int previousPage) {
		this.previousPage = previousPage;
	}

	/**
	 * @return the currentPage
	 */
	public int getCurrentPage() {
		return currentPage;
	}

	/**
	 * @param currentPage
	 *            the currentPage to set
	 */
	public void setCurrentPage(int currentPage) {
		this.currentPage = currentPage;
	}

	/**
	 * @return the pageSize
	 */
	public int getPageSize() {
		return pageSize;
	}

	/**
	 * @param pageSize
	 *            the pageSize to set
	 */
	public void setPageSize(int pageSize) {
		this.pageSize = pageSize;
	}

	/**
	 * @return the totalPages
	 */
	public int getTotalPages() {
		return totalPages;
	}

	/**
	 * @param totalPages
	 *            the totalPages to set
	 */
	public void setTotalPages(int totalPages) {
		this.totalPages = totalPages;
	}

	/**
	 * @return the totalRows
	 */
	public int getTotalRows() {
		return totalRows;
	}

	/**
	 * @param totalRows
	 *            the totalRows to set
	 */
	public void setTotalRows(int totalRows) {
		this.totalRows = totalRows;
	}

	/**
	 * @param hasNextPage
	 *            the hasNextPage to set
	 */
	public void setHasNextPage(boolean hasNextPage) {
		this.hasNextPage = hasNextPage;
	}

	/**
	 * @param hasPreviousPage
	 *            the hasPreviousPage to set
	 */
	public void setHasPreviousPage(boolean hasPreviousPage) {
		this.hasPreviousPage = hasPreviousPage;
	}

	/**
	 * @return the startNum
	 */
	public int getStartNum() {
		return startNum;
	}

	/**
	 * @param startNum
	 *            the startNum to set
	 */
	public void setStartNum(int startNum) {
		this.startNum = startNum;
	}

	public int getEndNum() {
		return endNum;
	}

	public void setEndNum(int endNum) {
		this.endNum = endNum;
	}

}