FileUtil.java

package com.llf.basemodel.utils;

import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.provider.OpenableColumns;
import android.text.format.Formatter;

import java.io.File;

/**
 * Created by ,llf on 2017/3/6.
 * 文件处理
 */

public class FileUtil {
    private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;

    private FileUtil() {

    }

    /**
     * 递归创建文件夹
     *
     * @param dirPath
     * @return 创建失败返回""
     */
    public static String createDir(String dirPath) {
        try {
            File file = new File(dirPath);
            if (file.getParentFile().exists()) {
                file.mkdir();
                return file.getAbsolutePath();
            } else {
                createDir(file.getParentFile().getAbsolutePath());
                file.mkdir();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return dirPath;
    }

    /**
     * 创建文件
     * @param file
     * @return 创建失败返回""
     */
    public static String createFile(File file) {
        try {
            if (file.getParentFile().exists()) {
                file.createNewFile();
                return file.getAbsolutePath();
            } else {
                createDir(file.getParentFile().getAbsolutePath());
                file.createNewFile();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }

    /**
     * 返回根缓存目录
     *
     * @return
     */
    public static String createRootPath(Context context) {
        String cacheRootPath = "";
        if (isSdCardAvailable()) {
            cacheRootPath = context.getExternalCacheDir().getPath();
        } else {
            cacheRootPath = context.getCacheDir().getPath();
        }
        return cacheRootPath;
    }

    /**
     * 获取文件名
     * @param fileName
     * @return
     */
    public static String[] splitFileName(String fileName) {
        String name = fileName;
        String extension = "";
        int i = fileName.lastIndexOf(".");
        if (i != -1) {
            name = fileName.substring(0, i);
            extension = fileName.substring(i);
        }

        return new String[]{name, extension};
    }

    /**
     * 根据uri获取文件路径
     * @param context
     * @param uri
     * @return
     */
    public static String getFileName(Context context, Uri uri) {
        String result = null;
        if (uri.getScheme().equals("content")) {
            Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
            try {
                if (cursor != null && cursor.moveToFirst()) {
                    result = cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (cursor != null) {
                    cursor.close();
                }
            }
        }
        if (result == null) {
            result = uri.getPath();
            int cut = result.lastIndexOf(File.separator);
            if (cut != -1) {
                result = result.substring(cut + 1);
            }
        }
        return result;
    }

    /**
     * 根据uri获取真文件路径
     * @param context
     * @param contentUri
     * @return
     */
    public static String getRealPathFromURI(Context context, Uri contentUri) {
        Cursor cursor = context.getContentResolver().query(contentUri, null, null, null, null);
        if (cursor == null) {
            return contentUri.getPath();
        } else {
            cursor.moveToFirst();
            int index = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA);
            String realPath = cursor.getString(index);
            cursor.close();
            return realPath;
        }
    }

    /**
     * 重命名
     * @param file
     * @param newName
     * @return
     */
    public static File rename(File file, String newName) {
        File newFile = new File(file.getParent(), newName);
        if (!newFile.equals(file)) {
            if (newFile.exists()) {
                if (newFile.delete()) {
                }
            }
            if (file.renameTo(newFile)) {
            }
        }
        return newFile;
    }

    /**
     * 文件是否存在
     * @param path
     * @return
     */
    public static boolean fileIsExists(String path) {
        try {
            File f = new File(path);
            if (!f.exists()) {
                return false;
            }
        } catch (Exception e) {

            return false;
        }
        return true;
    }

    /**
     * SD是否可用
     * @return
     */
    public static boolean isSdCardAvailable() {
        return Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState());
    }
    /**
     * 将字节数据转化为B,KB,MB
     */
    public static void formatSize(Context context,long number){
        Formatter.formatFileSize(context,number);
    }
}