Class GaugeBandsRenderer

java.lang.Object

com.arbergashi.charts.render.BaseRenderer

com.arbergashi.charts.render.circular.GaugeBandsRenderer

All Implemented Interfaces:

ChartRenderer

public final class GaugeBandsRenderer
extends BaseRenderer

GaugeBandsRenderer renders a gauge with colored bands (green/yellow/red), suitable for business KPIs.

Contract:

• Uses first data point as value.
• Range uses PlotContext y-range (preferred) and falls back to ChartPoint min/max or 0..100.
• Bands are configured via ChartAssets key chart.gaugeBands.bands.

Band format (UTF-8 properties safe):

 start,end,color; start,end,color; ...
 example: 0,60,#22c55e;60,85,#f59e0b;85,100,#ef4444

Since:

2025-06-01

Version:

1.0.0

Author:

Arber Gashi

Field Summary

Fields inherited from class BaseRenderer

PIXEL_BUF, PIXEL_BUF4

Constructor Summary

Constructors

Constructor	Description
GaugeBandsRenderer()

Method Summary

Modifier and Type	Method	Description
protected void	drawData(Graphics2D g2, ChartModel model, PlotContext context)	Implementation-specific drawing logic.
Optional<Integer>	getPointAt(Point2D pixel, ChartModel model, PlotContext context)	Returns the data index nearest to the given pixel coordinate, if supported.
boolean	isLegendRequired()	Indicates whether this renderer should appear in the legend.

Methods inherited from class BaseRenderer

drawHighlightPoint, drawI18nLabel, drawLabel, getArc, getCachedFont, getCachedGradient, getCachedStroke, getCachedStroke, getCachedStroke, getCubicCurve, getEllipse, getId, getLayerIndex, getLegendColor, getLine, getName, getPathCache, getRect, getRoundRectangle, getSeriesColor, getSeriesStroke, getTheme, getTooltipText, isMultiColor, pBuffer, pBuffer4, render, resolveTheme, seriesOrBase, setLayerIndex, setMultiColor, setTheme, setupQualityHints, themeAccent, themeAxisLabel, themeBackground, themeBearish, themeBullish, themeForeground, themeGrid, themeSeries

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface ChartRenderer

clearHover, createContext, getFocusValues, getPreferredYRange, renderEmptyState, supportsEmptyState

Constructor Details

GaugeBandsRenderer

public GaugeBandsRenderer()

Method Details

isLegendRequired

public boolean isLegendRequired()

Description copied from class: BaseRenderer

Indicates whether this renderer should appear in the legend.

Specified by:

isLegendRequired in interface ChartRenderer

Overrides:

isLegendRequired in class BaseRenderer

Returns:

true if the renderer should appear in the legend

drawData

protected void drawData(Graphics2D g2,
 ChartModel model,
 PlotContext context)

Description copied from class: BaseRenderer

Implementation-specific drawing logic. Must follow Zero-Allocation rules.

Specified by:

drawData in class BaseRenderer

getPointAt

public Optional<Integer> getPointAt(Point2D pixel,
 ChartModel model,
 PlotContext context)

Description copied from class: BaseRenderer

Returns the data index nearest to the given pixel coordinate, if supported.

Specified by:

getPointAt in interface ChartRenderer

Overrides:

getPointAt in class BaseRenderer

Parameters:

pixel - mouse/crosshair position in component coordinates

model - data model for this layer

context - current plot context

Returns:

optional point index