android图片文件的路径地址与Uri的相互转换方法

public static String getRealFilePath( final Context context, final Uri uri ) {
  if ( null == uri ) return null;
  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 ) ) {
    Cursor cursor = context.getContentResolver().query( uri, new String[] { ImageColumns.DATA }, null, null, null );
    if ( null != cursor ) {
      if ( cursor.moveToFirst() ) {
        int index = cursor.getColumnIndex( ImageColumns.DATA );
        if ( index > -1 ) {
          data = cursor.getString( index );
        }
      }
      cursor.close();
    }
  }
  return data
  }

  String type = Utils.ensureNotNull(intent.getType());
        Log.d(TAG, "uri is " + uri);
        if (uri.getScheme().equals("file") && (type.contains("image/"))) {
          String path = uri.getEncodedPath();
          Log.d(TAG, "path1 is " + path);
          if (path != null) {
            path = Uri.decode(path);
            Log.d(TAG, "path2 is " + path);
            ContentResolver cr = this.getContentResolver();
            StringBuffer buff = new StringBuffer();
            buff.append("(")
                .append(Images.ImageColumns.DATA)
                .append("=")
                .append("'" + path + "'")
                .append(")");
            Cursor cur = cr.query(
                Images.Media.EXTERNAL_CONTENT_URI,
                new String[] { Images.ImageColumns._ID },
                buff.toString(), null, null);
            int index = 0;
            for (cur.moveToFirst(); !cur.isAfterLast(); cur
                .moveToNext()) {
              index = cur.getColumnIndex(Images.ImageColumns._ID);
              // set _id value
              index = cur.getInt(index);
            }
            if (index == 0) {
              //do nothing
            } else {
              Uri uri_temp = Uri
                  .parse("content://media/external/images/media/"
                      + index);
              Log.d(TAG, "uri_temp is " + uri_temp);
              if (uri_temp != null) {
                uri = uri_temp;
              }
            }
          }
        }