分页计算

package com.dxcollector.commen;
/**
 * 计算分页或线程数
 * 
 * @author 忧里修斯
 *
 */
public class CalcuPage {
	
	int total;
	int limit;
	/**
	 * @param total 总页数
	 * @param limit 每页显示的页数
	 */
	public CalcuPage(int total,int limit){
		
		this.total = total;
		this.limit = limit;
	}
	
	/**
	 * 获取总页数
	 */
	public int getPageSize(){
		
		if(total == 0){
			return 0;
		}else{
			if(total%limit == 0){
				return total/limit;
			}else{
				return total/limit+1;
			}
		}
	}
	
	/**
	 * 根据当前页获取起始位置
	 */
	public int getStart(int currentPage){
		if(currentPage == 1){
			return 0;
		}else{
			return (currentPage-1)*limit+1;
		}
	}
	
	/**
	 * 根据当前页获取结束位置
	 */
	public int getEnd(int currentPage){
		
		if(currentPage == 1){
			return limit;
		}else if(currentPage != getPageSize()){
			return getStart(currentPage)+limit-1;
		}else{
			return total;
		}
		
		
	}
	
	public static void main(String[] args) {
		
		CalcuPage c = new CalcuPage(10,3);
		
		System.out.println("总页数："+c.getPageSize());
		System.out.println("起始："+c.getStart(4));
		System.out.println("结束："+c.getEnd(4));
	}
}