邏輯分頁之PageBean

PageBean：

• 基本需求：具有前臺頁面分頁所需的所有參數內容
• 特點：具有邏輯分頁功能
• 原理：利用List的subList實現對當前頁數據的截取
• 具體代碼如下：

package com.java.utils;

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

public class PageBean<T> implements Serializable{
	
	private static final long serialVersionUID = 787170437337348516L;
	
	//每頁顯記錄的條數
	private Integer pageSize;
	//當前頁
	private Integer currentPage;
	//總頁數
	private Integer totalPage;
	//總記錄數
	private Integer totalRecord;
	//要顯示的數據
	private List<T> dataList;
	
	public PageBean() {
	}
	/**
	 * 邏輯分頁
	 * @param pageNum	當前頁
	 * @param pageSize	當前頁顯示的記錄條數數
	 * @param sourceList	所有數據集合
	 */
	public PageBean(Integer pageNum, Integer pageSize, List<T> sourceList){
		//總記錄數
		this.totalRecord = sourceList.size();
		//每頁顯示的記錄條數
		this.pageSize = pageSize;
		//總頁數
		this.totalPage = (this.totalRecord+this.pageSize-1)/this.pageSize;
		//當前頁小於1則當前頁等於1
		pageNum = pageNum >= 1 ? pageNum : 1;
		//當前頁
		this.currentPage = pageNum >= totalPage ? totalPage : pageNum;
		
		//起始索引
		Integer fromIndex = (this.currentPage-1) * this.pageSize;
		//結束索引
		Integer toIndex = this.pageSize*this.currentPage >= this.totalRecord ? this.totalRecord : this.pageSize*this.currentPage;
		//當前頁顯示的記錄
		this.dataList = sourceList.subList(fromIndex, toIndex);
	}
	/**
	 * 通過構造函數生成一個Pager對象
	 * @param currentPage	當前頁
	 * @param pageSize	當前頁顯示的記錄條數
	 * @param totalPage	總頁數
	 * @param totalRecord	總記錄數
	 * @param dataList	當前頁要顯示的數據
	 */
	public PageBean(Integer currentPage, Integer pageSize, Integer totalPage, Integer totalRecord, List<T> dataList) {
		this.pageSize = pageSize;
		this.currentPage = currentPage;
		this.totalPage = totalPage;
		this.totalRecord = totalRecord;
		this.dataList = dataList;
	}

	public Integer getPageSize() {
		return pageSize;
	}
	public void setPageSize(Integer pageSize) {
		this.pageSize = pageSize;
	}
	public Integer getCurrentPage() {
		return currentPage;
	}
	public void setCurrentPage(Integer currentPage) {
		this.currentPage = currentPage;
	}
	public Integer getTotalPage() {
		return totalPage;
	}
	public void setTotalPage(Integer totalPage) {
		this.totalPage = totalPage;
	}
	public Integer getTotalRecord() {
		return totalRecord;
	}
	public void setTotalRecord(Integer totalRecord) {
		this.totalRecord = totalRecord;
	}
	public List<T> getDataList() {
		return dataList;
	}
	public void setDataList(List<T> dataList) {
		this.dataList = dataList;
	}
	
}