Package org.openhab.core.ui.chart

Interface ChartProvider

@NonNullByDefault
public interface ChartProvider

Defines the interface for chart providers. A chart provider interfaces with the persistence store to get the data and receives parameters from the UI chart servlet and returns a chart image object (PNG).

Author:

Chris Jackson - Initial contribution, Holger Reichert - Support for themes, DPI, legend hiding, Jan N. Klug - add y-axis label formatter

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static enum	ChartProvider.ImageType	Provides a list of image types

Method Summary

Modifier and Type	Method	Description
BufferedImage	createChart(@Nullable String service, @Nullable String theme, ZonedDateTime startTime, ZonedDateTime endTime, int height, int width, @Nullable String items, @Nullable String groups, @Nullable Integer dpi, @Nullable Boolean legend)	Creates a chart object.
default BufferedImage	createChart(@Nullable String service, @Nullable String theme, ZonedDateTime startTime, ZonedDateTime endTime, int height, int width, @Nullable String items, @Nullable String groups, @Nullable Integer dpi, @Nullable String yAxisDecimalPattern, @Nullable Boolean legend)	Creates a chart object.
ChartProvider.ImageType	getChartType()	Gets the type of data that will be written by the chart.
String	getName()	Gets the name of this chart provider.

Method Details

getName

String getName()

Gets the name of this chart provider.

Returns:

String containing the provider name

createChart

BufferedImage createChart(@Nullable String service,
 @Nullable String theme,
 ZonedDateTime startTime,
 ZonedDateTime endTime,
 int height,
 int width,
 @Nullable String items,
 @Nullable String groups,
 @Nullable Integer dpi,
 @Nullable Boolean legend)
                   throws ItemNotFoundException

Creates a chart object. This sets the initial parameters for the chart before the items are added

Parameters:

service - A string containing the name of the persistence service. May be null in which case the chart provider can decide itself which store to use.

theme - A string containing a theme name for the chart. The provider should store its own themes. May be null to use a default theme.

startTime - The start time of the chart

endTime - The end time of the chart

height - The height of the chart

width - The width of the chart

items - The items to display on the chart

groups - The groups to display on the chart

dpi - The DPI (dots per inch) value, can be null

legend - Show the legend? If null, the ChartProvider should make his own decision.

Returns:

BufferedImage object if the chart is rendered correctly, otherwise null.

Throws:

ItemNotFoundException - if an item or group is not found

IllegalArgumentException - if an invalid argument is passed

createChart

default BufferedImage createChart(@Nullable String service,
 @Nullable String theme,
 ZonedDateTime startTime,
 ZonedDateTime endTime,
 int height,
 int width,
 @Nullable String items,
 @Nullable String groups,
 @Nullable Integer dpi,
 @Nullable String yAxisDecimalPattern,
 @Nullable Boolean legend)
                           throws ItemNotFoundException

Creates a chart object. This sets the initial parameters for the chart before the items are added

Parameters:

service - A string containing the name of the persistence service. May be null in which case the chart provider can decide itself which store to use.

theme - A string containing a theme name for the chart. The provider should store its own themes. May be null to use a default theme.

startTime - The start time of the chart

endTime - The end time of the chart

height - The height of the chart

width - The width of the chart

items - The items to display on the chart

groups - The groups to display on the chart

dpi - The DPI (dots per inch) value, can be null

yAxisDecimalPattern - The format pattern for the y-axis labels

legend - Show the legend? If null, the ChartProvider should make his own decision.

Returns:

BufferedImage object if the chart is rendered correctly, otherwise null.

Throws:

ItemNotFoundException - if an item or group is not found

IllegalArgumentException - if an invalid argument is passed

getChartType

ChartProvider.ImageType getChartType()

Gets the type of data that will be written by the chart.

Returns:

ImageType