this.target = value;
    }

    public String getThumbnailId() {
        checkSpecifiedProperty("thumbnailId");
        return convertEmptyToNull(thumbnailId);
    }

    public void setThumbnailId(String value) {
        registerModifiedProperty("thumbnailId");
        this.thumbnailId = value;
    }

{
    "properties": {
      "thumbnail_id": {
        "type": "keyword"
      },
      "path": {
        "type": "keyword"
      },
      "generator": {
        "type": "keyword"
      },
      "target": {
        "type": "keyword"
      },
      "createdTime": {
        "type": "long"
      },
      "createdBy": {
        "type": "keyword"
      }
    }

            "type" : "keyword"
          },
          "path" : {
            "type" : "keyword"
          },
          "target" : {
            "type" : "keyword"
          },
          "thumbnail_id" : {
            "type" : "keyword"
          }
        }
      }
    },
    "settings" : {
      "index" : {
        "creation_date" : "1509021057304",
        "number_of_shards" : "5",

            doColumn("path");
        }

        public void columnTarget() {
            doColumn("target");
        }

        public void columnThumbnailId() {
            doColumn("thumbnail_id");
        }
    }

     *
     * @param thumbnailId the ID of the thumbnail to generate
     * @param outputFile the output file where the thumbnail should be saved
     * @return false always, as this generator does not create thumbnails
     */
    @Override
    public boolean generate(final String thumbnailId, final File outputFile) {
        return false;
    }

    /**

     *
     * @param thumbnailId the unique identifier for the thumbnail
     * @param outputFile the file where the generated thumbnail will be saved
     * @return true if the thumbnail was successfully generated, false otherwise
     */
    boolean generate(String thumbnailId, File outputFile);

    /**
     * Checks if this generator can handle the given document.

        // Test that generate always returns false
        File outputFile = new File("test.jpg");
        assertFalse(emptyGenerator.generate("thumbnailId", outputFile));
        assertFalse(emptyGenerator.generate(null, outputFile));
        assertFalse(emptyGenerator.generate("thumbnailId", null));
        assertFalse(emptyGenerator.generate(null, null));
    }

    @Test
    public void test_destroy() {