java分页工具类

在最近的项目中需要用到分页，所以自己写了个分页工具。

主要的原理就是将数据库取出的数据存储到List中，然后以设置的每页条数进行逐页处理。

一共分为两个类，Page类用于存储页面信息，Pagination类用于页面的操作，例如上一页、下一页、跳转等。

经验不足，写的代码很罗嗦，而且重复无用的东西太多，引以为戒

Page类：

import java.util.List;

public class Page<T> {
	private int totalPage;				//总页数
	private int currentPage;			//当前页数
	private int totalCount;				//内容总条数
	private List<T> currentContent;//当前页的内容
	
	public Page(){}
	public Page(int totalPage,int currentPage,int totalCount,List<T> currentContent){
		this.totalPage=totalPage;
		this.currentPage=currentPage;
		this.totalCount=totalCount;
		this.currentContent=currentContent;
	}
	
	
	public int getTotalPage() {
		return totalPage;
	}
	public void setTotalPage(int totalPage) {
		this.totalPage = totalPage;
	}
	public int getCurrentPage() {
		return currentPage;
	}
	public void setCurrentPage(int currentPage) {
		this.currentPage = currentPage;
	}
	public int getTotalCount() {
		return totalCount;
	}
	public void setTotalCount(int totalCount) {
		this.totalCount = totalCount;
	}
	public List<T> getCurrentContent() {
		return currentContent;
	}
	public void setCurrentContent(List<T> currentContent) {
		this.currentContent = currentContent;
	}
}

Pagination类：

import java.util.LinkedList;
import java.util.List;

/**
 * 
 * @author wangle
 * @date 2015.8.16
 * @param <T> 页面显示的内容
 * @description 分页封装类
 */
public class Pagination<T> {
	private int totalPage;				//总页数
	private int currentPage;			//当前页数
	private int totalCount;				//内容总条数
	private final int PAGE_SIZE=10;		//每页显示的条数
	private List<T> allContent;			//所有的内容
	private List<T> currentContent;		//当前页的内容

	/**
	 * @constructor 构造函数
	 */
	public Pagination(){}
	/**
	 * @constructor 
	 * @param content 初始化的数据
	 */
	public Pagination(List<T> content){
		this.allContent=content;
		this.totalCount=content.size();
		this.currentPage=1;
		if(totalCount<=PAGE_SIZE){
			totalPage=1;
			currentContent=allContent;
		}
		else if(totalCount%PAGE_SIZE==0){
			totalPage=totalCount/PAGE_SIZE;
		}
		else{
			totalPage=totalCount/PAGE_SIZE+1;
		}
	}
	/**
	 * 
	 * @return 返回下一页
	 */
	public Page<T> next(){
		if(totalPage!=1){
			if(currentPage<totalPage-1){
				List<T> list = new LinkedList<T>();
				for(int i=0;i<PAGE_SIZE;i++){
					list.add(allContent.get(PAGE_SIZE*currentPage+i));
				}
				currentPage++;
				currentContent=list;
				return new Page<T>(totalPage,currentPage,totalCount,currentContent);
			}
			else if(currentPage==totalPage-1){
				LinkedList<T> list = new LinkedList<T>();
				for(int i=0;i<((totalCount%PAGE_SIZE==0)?PAGE_SIZE:totalCount%PAGE_SIZE);i++){
					list.add(allContent.get(PAGE_SIZE*currentPage+i));
				}
				currentPage++;
				currentContent=list;
				return new Page<T>(totalPage,currentPage,totalCount,currentContent);
			}
			else{
				return null;
			}
		}
		else{
			return new Page<T>(totalPage,currentPage,totalCount,currentContent);
		}
	}
	/**
	 * 
	 * @return 返回上一页
	 */
	public Page<T> last(){
		if(totalPage!=1){
			if(currentPage>1){
				currentPage--;
				LinkedList<T> list = new LinkedList<T>();
				for(int i=0;i<PAGE_SIZE;i++){
					list.add(allContent.get(PAGE_SIZE*(currentPage-1)+i));
				}
				currentContent=list;
				return new Page<T>(totalPage,currentPage,totalCount,currentContent);
			}
			else{
				LinkedList<T> list = new LinkedList<T>();
				for(int i=0;i<((totalCount%PAGE_SIZE==0)?PAGE_SIZE:totalCount%PAGE_SIZE);i++){
					list.add(allContent.get(PAGE_SIZE*(currentPage-1)+i));
				}
				currentContent=list;
				return new Page<T>(totalPage,currentPage,totalCount,currentContent);
			}
		}
		else{
			return new Page<T>(totalPage,currentPage,totalCount,currentContent);
		}
	}
	/**
	 * 
	 * @param number 要跳转的页数
	 * @return 返回页面内容
	 */
	public Page<T> getByPageNumber(int number){
		if(number<totalPage){
			LinkedList<T> list = new LinkedList<T>();
			for(int i=0;i<PAGE_SIZE;i++){
				list.add(allContent.get(PAGE_SIZE*(number-1)+i));
			}
			currentContent=list;
			currentPage=number;
			return new Page<T>(totalPage,currentPage,totalCount,currentContent);
		}
		else if(number>totalPage){
			return null;
		}
		else{
			LinkedList<T> list = new LinkedList<T>();
			for(int i=0;i<((totalCount%PAGE_SIZE==0)?PAGE_SIZE:totalCount%PAGE_SIZE);i++){
				list.add(allContent.get(PAGE_SIZE*(number-1)+i));
			}
			currentContent=list;
			currentPage=number;
			return new Page<T>(totalPage,currentPage,totalCount,currentContent);
		}
	}
	/**
	 * 
	 * @return 返回第一页
	 */
	public Page<T> getFirstPage(){
		currentPage=1;
		return getByPageNumber(1);
	}
	/**
	 * 
	 * @return 返回最后一页
	 */
	public Page<T> getLastPage(){
		currentPage=totalPage;
		return getByPageNumber(totalPage);
	}
	
	//getter和setter
	public int getTotalPage() {
		return totalPage;
	}
	public void setTotalPage(int totalPage) {
		this.totalPage = totalPage;
	}
	public int getCurrentPage() {
		return currentPage;
	}
	public void setCurrentPage(int currentPage) {
		this.currentPage = currentPage;
	}
	public int getPAGE_SIZE() {
		return PAGE_SIZE;
	}
	public List<T> getAllContent() {
		return allContent;
	}
	public void setAllContent(List<T> content){
		this.allContent=content;
		this.totalCount=content.size();
		this.currentPage=1;
		if(totalCount<=PAGE_SIZE){
			totalPage=1;
			currentContent=allContent;
		}
		else if(totalCount%PAGE_SIZE==0){
			totalPage=totalCount/PAGE_SIZE;
		}
		else{
			totalPage=totalCount/PAGE_SIZE+1;
		}
	}
	public int getTotalCount() {
		return totalCount;
	}
	public void setTotalCount(int totalCount) {
		this.totalCount = totalCount;
	}
	public List<T> getCurrentConetnt() {
		return currentContent;
	}
	
}