android 透过文件路径，判断文件大小

1.用来判断文件大小的方法的类package com.email.filesize;import java.io.File;import java.io.FileInputStream;import java.text.DecimalFormat;public class GetFileSize {	public GetFileSize() {	}	public long getFileSizes(File f) throws Exception {		long s = 0;		if (f.exists()) {			FileInputStream fis = null;			fis = new FileInputStream(f);			s = fis.available();			fis.close();		} else {			f.createNewFile();			System.out.println("文件夹不存在");		}		return s;	}	/**	 * 递归	 * */	public long getFileSize(File f) {		long size = 0;		File flist[] = f.listFiles();		for (int i = 0; i < flist.length; i++) {			if (flist[i].isDirectory()) {				size = size + getFileSize(flist[i]);			} else {				size = size + flist[i].length();			}		}		return size;	}	/**	 * 转换文件大小	 * */	public String FormentFileSize(long fileS) {		DecimalFormat df = new DecimalFormat("#.00");		String fileSizeString = "";		if (fileS < 1024) {			fileSizeString = df.format((double) fileS) + "B";		} else if (fileS < 1048576) {			fileSizeString = df.format((double) fileS / 1024) + "K";		} else if (fileS < 1073741824) {			fileSizeString = df.format((double) fileS / 1048576) + "M";		} else {			fileSizeString = df.format((double) fileS / 1073741824) + "G";		}		return fileSizeString;	}//	/**//	 * 递归求取目录文件个数//	 * *///	public long getlist(File f) {//		long size = 0;//		File flist[] = f.listFiles();//		System.out.println("-------------" + flist.length);//		size = flist.length;//		for (int i = 0; i < flist.length; i++) {//			if (flist[i].isDirectory()) {//				size = size + getlist(flist[i]);//				size--;//			}//		}//		return size;//	}}2.判断文件大小，在主函数中写的语句GetFileSize g = new GetFileSize();String path = File.separator + "mnt" + File.separator + "sdcard" + File.separator + "1.txt";File ff = new File(path);try {       l = g.getFileSizes(ff);    } catch (Exception e) {      e.printStackTrace();    } System.out.println(path + "文件的大小为：" + g.FormentFileSize(l));