Package com.vaadin.flow.component.ai.chart

Class DefaultDataConverter

java.lang.Object
com.vaadin.flow.component.ai.chart.DefaultDataConverter
All Implemented Interfaces:
DataConverter, Serializable
public class DefaultDataConverter extends Object implements DataConverter
Default implementation of DataConverter that handles common data conversion patterns for various chart types.

This converter uses column-name-based pattern matching to determine the appropriate series type and data structure. All expected column names are defined in ColumnNames and prefixed with "_" to avoid collisions with real data columns. Patterns are checked in priority order from most-specific to least-specific:

  1. OHLC/Candlestick (_open, _high, _low, _close)
  2. BoxPlot (_low, _q1, _median, _q3, _high)
  3. Organization (_id, _name, _parent, _title; optionally _description, _image, _color)
  4. Gantt (_name, _start, _end; optionally _id, _parent, _dependency, _completed, _color)
  5. Treemap (_id, _parent, _value)
  6. Sankey (_from, _to, _weight)
  7. Heatmap (_x, _y, _value)
  8. XRange (_x, _x2, _y)
  9. Timeline (_name, _label, _description)
  10. Bubble (_x, _y, _z)
  11. Flags (_title, optionally _text; requires absence of _parent to avoid matching Organization/Treemap data)
  12. Range (_low, _high)
  13. Bullet (_y, _target)
  14. Waterfall (_y, _waterfall_type; type values are "sum" and "intermediate", case-insensitive; null or absent for regular data points)
  15. Fallback: first non-numeric column as category, first numeric column as value

Additionally, any pattern that produces a DataSeriesItem (or subclass) supports an optional _color column. If present, the value is used to set the item's color via SolidColor(String). The column is never treated as data, so the fallback skips it when it picks the category and value columns.

Column name matching is case-insensitive. Column names are determined from the first row; subsequent rows with missing keys will yield null for those columns.

If the data contains a _series column, rows are automatically grouped by that column's value and each group is converted into a separate named series. The _series column is removed before pattern matching so it does not interfere with chart type detection.

Since:
25.3
Author:
Vaadin Ltd
See Also:

  • Constructor Details

    • DefaultDataConverter

      public DefaultDataConverter()

  • Method Details

    • convertToSeries

      public List<com.vaadin.flow.component.charts.model.Series> convertToSeries(List<Map<String,Object>> data)
      Description copied from interface: DataConverter
      Converts tabular data into one or more chart series.

      Each element in the input list represents a single row, with column names as keys and column values as values.

      Specified by:
      convertToSeries in interface DataConverter
      Parameters:
      data - the tabular data to convert, not null
      Returns:
      a list of series ready for use in a chart, never null and never empty