Android根据Uri获取文件的绝对路径

public class Uri2PathUtil {

    //复杂版处理  (适配多种API)
    public static String getRealPathFromUri(Context context, Uri uri) {
        int sdkVersion = Build.VERSION.SDK_INT;
        if (sdkVersion < 11) return getRealPathFromUri_BelowApi11(context, uri);
        if (sdkVersion < 19) return getRealPathFromUri_Api11To18(context, uri);
        else return getRealPathFromUri_AboveApi19(context, uri);
    }

    /**
     * 适配api19以上,根据uri获取图片的绝对路径
     */
    @TargetApi(Build.VERSION_CODES.KITKAT)
    private static String getRealPathFromUri_AboveApi19(Context context, Uri uri) {
        if (DocumentsContract.isDocumentUri(context, uri)) {
            if (isExternalStorageDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    return Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            } else if (isDownloadsDocument(uri)) {
                final String id = DocumentsContract.getDocumentId(uri);
                final Uri contentUri = ContentUris.withAppendedId(
                        Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));

                return getDataColumn(context, contentUri, null, null);
            } else if (isMediaDocument(uri)) {
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];

                Uri contentUri;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                } else {
                    contentUri = MediaStore.Files.getContentUri("external");
                }

                final String selection = "_id=?";
                final String[] selectionArgs = new String[]{split[1]};
                return getDataColumn(context, contentUri, selection, selectionArgs);
            }


        } else if ("content".equalsIgnoreCase(uri.getScheme())) {
            return getDataColumn(context, uri, null, null);
        } else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }

        return null;
    }

    /**
     * 适配api11-api18,根据uri获取图片的绝对路径
     */
    private static String getRealPathFromUri_Api11To18(Context context, Uri uri) {
        String filePath = null;
        String[] projection = {MediaStore.Images.Media.DATA};
        //这个有两个包不知道是哪个。。。。不过这个复杂版一般用不到
        CursorLoader loader = new CursorLoader(context, uri, projection, null, null, null);
        Cursor cursor = loader.loadInBackground();

        if (cursor != null) {
            cursor.moveToFirst();
            filePath = cursor.getString(cursor.getColumnIndex(projection[0]));
            cursor.close();
        }
        return filePath;
    }

    /**
     * 适配api11以下(不包括api11),根据uri获取图片的绝对路径
     */
    private static String getRealPathFromUri_BelowApi11(Context context, Uri uri) {
        String filePath = null;
        String[] projection = {MediaStore.Images.Media.DATA};
        Cursor cursor = context.getContentResolver().query(uri, projection, null, null, null);
        if (cursor != null && cursor.moveToFirst()) {
            filePath = cursor.getString(cursor.getColumnIndex(projection[0]));
            cursor.close();
        }
        return filePath;
    }

    /**
     * Get the value of the data column for this Uri. This is useful for
     * MediaStore Uris, and other file-based ContentProviders.
     *
     * @param context       The context.
     * @param uri           The Uri to query.
     * @param selection     (Optional) Filter used in the query.
     * @param selectionArgs (Optional) Selection arguments used in the query.
     * @return The value of the _data column, which is typically a file path.
     */
    public static String getDataColumn(Context context, Uri uri, String selection,
                                       String[] selectionArgs) {
        Cursor cursor = null;
        String column = MediaStore.MediaColumns.DATA;
        String[] projection = {column};
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
                    null);
            if (cursor != null && cursor.moveToFirst()) {
                int column_index = cursor.getColumnIndexOrThrow(column);
                return cursor.getString(column_index);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (cursor != null)
                cursor.close();
        }
        return null;
    }

    /**
     * @param uri The Uri to check.
     * @return Whether the Uri authority is ExternalStorageProvider.
     */
    public static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

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

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