uri转真实path

public class UriToPathUtils {
    /**
     * 根据Uri获取图片的绝对路径
     *
     * @param context 上下文对象
     * @param uri     图片的Uri
     * @return 如果Uri对应的图片存在, 那么返回该图片的绝对路径, 否则返回null
     */
    public static String getRealPathFromUri(Context context, Uri uri) {

        // Uri分为三个部分   域名://主机名/路径/id
        // content://media/extenral/images/media/17766
        // content://com.android.providers.media.documents/document/image:2706
        // file://com.xxxx.xxxxx ---- 7.0 有限制

        int sdkVersion = Build.VERSION.SDK_INT;
        if (sdkVersion >= 19) { // api >= 19
            return getRealPathFromUriAboveApi19(context, uri);
        } else { // api < 19
            return getRealPathFromUriBelowAPI19(context, uri);
        }
    }

    /**
     * 适配api19以下(不包括api19),根据uri获取图片的绝对路径
     *
     * @param context 上下文对象
     * @param uri     图片的Uri
     * @return 如果Uri对应的图片存在, 那么返回该图片的绝对路径, 否则返回null
     */
    private static String getRealPathFromUriBelowAPI19(Context context, Uri uri) {
        final String scheme = uri.getScheme();
        String data = null;
        if (scheme == null)
            data = uri.getPath();
        else if (ContentResolver.SCHEME_FILE.equals(scheme)) {
            data = uri.getPath();
        } else if (ContentResolver.SCHEME_CONTENT.equals(scheme)) {
            data = getDataColumn(context, uri, null, null);
        }
        return data;
    }

    /**
     * 适配api19及以上,根据uri获取图片的绝对路径
     *
     * @param context 上下文对象
     * @param uri     图片的Uri
     * @return 如果Uri对应的图片存在, 那么返回该图片的绝对路径, 否则返回null
     */
    @SuppressLint("NewApi")
    private static String getRealPathFromUriAboveApi19(Context context, Uri uri) {
        String filePath = null;
        if (DocumentsContract.isDocumentUri(context, uri)) {
            // 如果是document类型的 uri, 则通过document id来进行处理
            String documentId = DocumentsContract.getDocumentId(uri);
            if (isMediaDocument(uri)) { // MediaProvider
                final String[] divide = documentId.split(":");
                final String type = divide[0];
                Uri mediaUri = null;
                if ("image".equals(type)) {
                    mediaUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    mediaUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    mediaUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                } else {
                    return null;
                }
                String selection = BaseColumns._ID + "=?";
                String[] selectionArgs = {divide[1]};
                filePath = getDataColumn(context, mediaUri, selection, selectionArgs);
            } else if (isDownloadsDocument(uri)) { // DownloadsProvider
                Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(documentId));
                filePath = getDataColumn(context, contentUri, null, null);
            }else if(isExternalStorageDocument(uri)) {
                String [] split = documentId.split(":");
                if(split.length >= 2) {
                    String type = split[0];
                    if("primary".equalsIgnoreCase(type)) {
                        filePath = Environment.getExternalStorageDirectory() + "/" + split[1];
                    }
                }
            }
        } else if (ContentResolver.SCHEME_CONTENT.equalsIgnoreCase(uri.getScheme())){
            // 如果是 content 类型的 Uri
            filePath = getDataColumn(context, uri, null, null);
        } else if (ContentResolver.SCHEME_FILE.equals(uri.getScheme())) {
            // 如果是 file 类型的 Uri,直接获取图片对应的路径
            filePath = uri.getPath();
        }
        return filePath;
    }

    /**
     * 获取数据库表中的 _data 列，即返回Uri对应的文件路径
     * @return
     */
    private static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
        String path = null;

        String[] projection = new String[]{MediaStore.Images.Media.DATA};
        Cursor cursor = null;
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
            if (cursor != null && cursor.moveToFirst()) {
                int columnIndex = cursor.getColumnIndexOrThrow(projection[0]);
                path = cursor.getString(columnIndex);
            }
        } catch (Exception e) {
            if (cursor != null) {
                cursor.close();
            }
        }
        return path;
    }

    /**
     * @param uri the Uri to check
     * @return Whether the Uri authority is MediaProvider
     */
    private static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri the Uri to check
     * @return Whether the Uri authority is DownloadsProvider
     */
    private static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }

    private static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

}