LegendComposer

java.lang.Object

org.rrd4j.graph.LegendComposer

All Implemented Interfaces:: RrdGraphConstants

class LegendComposerextends Object implements RrdGraphConstants

Handles legend composition and layout for RRD graphs. Manages text positioning, alignment, and spacing within the legend area.

Nested Class Summary
Nested Classes
Modifier and Type
Class
Description
(package private) class
LegendComposer.Line
Line-style graph element with configurable width and color.
Nested classes/interfaces inherited from interface RrdGraphConstants
RrdGraphConstants.FontConstructor, RrdGraphConstants.FontTag
Modifier and Type
Interface
Description
static class
RrdGraphConstants.FontConstructor
Font constructor, to use embedded fonts.
static enum
RrdGraphConstants.FontTag
Allowed font tag names which can be used in RrdGraphDef.setFont(org.rrd4j.graph.RrdGraphConstants.FontTag, java.awt.Font) method
Field Summary
Fields
Modifier and Type
Field
Description
private final double
boxSpace
Space around legend boxes
private final RrdGraphDef
gdef
The graph definition being composed.
private final double
interLegendSpace
Spacing between legend elements
private final double
leading
Line height for legend text
private final int
legWidth
Available width for legend content
private final int
legX
X-coordinate for legend placement
private int
legY
Y-coordinate for legend placement
private final double
smallLeading
Line height for small legend text
private final ImageWorker
worker
Where the legend is drawn.
Fields inherited from interface RrdGraphConstants
BLIND_COLOR, COLOR_ARROW, COLOR_BACK, COLOR_CANVAS, COLOR_FONT, COLOR_FRAME, COLOR_GRID, COLOR_MGRID, COLOR_SHADEA, COLOR_SHADEB, COLOR_XAXIS, COLOR_YAXIS, DAY, DEFAULT_ARROW_COLOR, DEFAULT_BACK_COLOR, DEFAULT_BASE, DEFAULT_CANVAS_COLOR, DEFAULT_END, DEFAULT_FONT_COLOR, DEFAULT_FRAME_COLOR, DEFAULT_GRID_COLOR, DEFAULT_HEIGHT, DEFAULT_IMAGE_FORMAT, DEFAULT_IMAGE_QUALITY, DEFAULT_LARGE_FONT, DEFAULT_MGRID_COLOR, DEFAULT_SHADEA_COLOR, DEFAULT_SHADEB_COLOR, DEFAULT_SMALL_FONT, DEFAULT_START, DEFAULT_UNITS_LENGTH, DEFAULT_WIDTH, DEFAULT_XAXIS_COLOR, DEFAULT_YAXIS_COLOR, FIRST_DAY_OF_WEEK, FONTTAG_AXIS, FONTTAG_DEFAULT, FONTTAG_LEGEND, FONTTAG_TITLE, FONTTAG_UNIT, FONTTAG_WATERMARK, FRIDAY, GATOR_FONT, GRID_STROKE, HH_MM, HOUR, IN_MEMORY_IMAGE, LEGEND_BOX, LEGEND_BOX_SPACE, LEGEND_INTERSPACING, LEGEND_LEADING, LEGEND_LEADING_SMALL, MINUTE, MONDAY, MONTH, PADDING_BOTTOM, PADDING_LEFT, PADDING_LEGEND, PADDING_PLOT, PADDING_RIGHT, PADDING_TITLE, PADDING_TOP, PADDING_VLABEL, PROPERTYFONTBOLD, PROPERTYFONTBOLDURL, PROPERTYFONTPLAIN, PROPERTYFONTPLAINURL, PROPERTYFONTSPROPERTIES, PROPERTYFONTSURL, SATURDAY, SECOND, SERIES_DOT, SUNDAY, THURSDAY, TICK_STROKE, TUESDAY, WEDNESDAY, WEEK, YEAR
Modifier and Type
Field
Description
static final Color
BLIND_COLOR
An transparent color
static final int
COLOR_ARROW
Index of the arrow color.
static final int
COLOR_BACK
Index of the background color.
static final int
COLOR_CANVAS
Index of the canvas color.
static final int
COLOR_FONT
Index of the font color.
static final int
COLOR_FRAME
Index of the frame color.
static final int
COLOR_GRID
Index of the minor grid color.
static final int
COLOR_MGRID
Index of the major grid color.
static final int
COLOR_SHADEA
Index of the top-left graph shade color.
static final int
COLOR_SHADEB
Index of the bottom-right graph shade color.
static final int
COLOR_XAXIS
Index of the x-axis color.
static final int
COLOR_YAXIS
Index of the yaxis color.
static final int
DAY
Constant to represent day
static final Color
DEFAULT_ARROW_COLOR
Default arrow color
static final Color
DEFAULT_BACK_COLOR
Default graph background color
static final double
DEFAULT_BASE
Default value base
static final Color
DEFAULT_CANVAS_COLOR
Default graph canvas color
static final String
DEFAULT_END
Default graph ending time
static final Color
DEFAULT_FONT_COLOR
Default font color
static final Color
DEFAULT_FRAME_COLOR
Default frame color
static final Color
DEFAULT_GRID_COLOR
Default minor grid color
static final int
DEFAULT_HEIGHT
Default graph height
static final String
DEFAULT_IMAGE_FORMAT
Default image format
static final float
DEFAULT_IMAGE_QUALITY
Default image quality, used only for jpeg graphs
static final Font
DEFAULT_LARGE_FONT
Default graph large font
static final Color
DEFAULT_MGRID_COLOR
Default major grid color
static final Color
DEFAULT_SHADEA_COLOR
Default top-left graph shade color
static final Color
DEFAULT_SHADEB_COLOR
Default bottom-right graph shade color
static final Font
DEFAULT_SMALL_FONT
Default graph small font
static final String
DEFAULT_START
Default graph starting time
static final int
DEFAULT_UNITS_LENGTH
Default units length
static final int
DEFAULT_WIDTH
Default graph width
static final Color
DEFAULT_XAXIS_COLOR
Default x-axis color
static final Color
DEFAULT_YAXIS_COLOR
Default x-axis color
static final int
FIRST_DAY_OF_WEEK
Default first day of the week (obtained from the default locale)
static final RrdGraphConstants.FontTag
FONTTAG_AXIS
Axis font tag
static final RrdGraphConstants.FontTag
FONTTAG_DEFAULT
Default font tag
static final RrdGraphConstants.FontTag
FONTTAG_LEGEND
Legend font tag
static final RrdGraphConstants.FontTag
FONTTAG_TITLE
Title font tag
static final RrdGraphConstants.FontTag
FONTTAG_UNIT
Unit font tag
static final RrdGraphConstants.FontTag
FONTTAG_WATERMARK
Watermark font tag
static final int
FRIDAY
Constant to represent Friday
static final Font
GATOR_FONT
Font for the Gator
static final Stroke
GRID_STROKE
Stroke used to draw grid
static final String
HH_MM
HH:mm time format
static final int
HOUR
Constant to represent hour
static final String
IN_MEMORY_IMAGE
Constant to represent in-memory image name
static final double
LEGEND_BOX
Used internally
static final double
LEGEND_BOX_SPACE
Used internally
static final int
LEGEND_INTERSPACING
Used internally
static final double
LEGEND_LEADING
Used internally
static final double
LEGEND_LEADING_SMALL
Used internally
static final int
MINUTE
Constant to represent minute
static final int
MONDAY
Constant to represent Monday
static final int
MONTH
Constant to represent month
static final int
PADDING_BOTTOM
Used internally
static final int
PADDING_LEFT
Used internally
static final double
PADDING_LEGEND
Used internally
static final int
PADDING_PLOT
Used internally
static final int
PADDING_RIGHT
Used internally
static final int
PADDING_TITLE
Used internally
static final int
PADDING_TOP
Used internally
static final int
PADDING_VLABEL
Used internally
static final String
PROPERTYFONTBOLD
The name of the bold font, used to define the RrdGraphConstants.DEFAULT_LARGE_FONT.
static final String
PROPERTYFONTBOLDURL
A URL to the bold font, used to define the RrdGraphConstants.DEFAULT_LARGE_FONT.
static final String
PROPERTYFONTPLAIN
The name of the plain font, used to define the RrdGraphConstants.DEFAULT_SMALL_FONT and the RrdGraphConstants.GATOR_FONT.
static final String
PROPERTYFONTPLAINURL
A URL to the plain font, used to define the RrdGraphConstants.DEFAULT_SMALL_FONT and the RrdGraphConstants.GATOR_FONT.
static final String
PROPERTYFONTSPROPERTIES
The file that contains font configuration searched in the class path.
static final String
PROPERTYFONTSURL
A possible URL to a configuration file.
static final int
SATURDAY
Constant to represent Saturday
static final int
SECOND
Constant to represent second
static final float
SERIES_DOT
Ink length of one dot in a series line, in device pixels.
static final int
SUNDAY
Constant to represent Sunday
static final int
THURSDAY
Constant to represent Thursday
static final Stroke
TICK_STROKE
Stroke used to draw ticks
static final int
TUESDAY
Constant to represent Tuesday
static final int
WEDNESDAY
Constant to represent Wednesday
static final int
WEEK
Constant to represent week
static final int
YEAR
Constant to represent year
Constructor Summary
Constructors
Constructor
Description
LegendComposer(RrdGraphGenerator generator, int legX, int legY, int legWidth)
Creates a legend composer with specified positioning and dimensions.
Method Summary
All Methods
Modifier and Type
Method
Description
(package private) int
placeComments()
Lays out every valid graph comment as one or more legend lines
Methods inherited from class Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details
- gdef
  private final RrdGraphDef gdef
  The graph definition being composed.
- worker
  private final ImageWorker worker
  Where the legend is drawn.
- legX
  private final int legX
  X-coordinate for legend placement
- legY
  private int legY
  Y-coordinate for legend placement
- legWidth
  private final int legWidth
  Available width for legend content
- interLegendSpace
  private final double interLegendSpace
  Spacing between legend elements
- leading
  private final double leading
  Line height for legend text
- smallLeading
  private final double smallLeading
  Line height for small legend text
- boxSpace
  private final double boxSpace
  Space around legend boxes
Constructor Details
- LegendComposer
  LegendComposer(RrdGraphGenerator generator, int legX, int legY, int legWidth)
  Creates a legend composer with specified positioning and dimensions.
  Parameters:
  generator - graph generator for font and spacing calculations
  legX - x-coordinate for legend placement
  legY - y-coordinate for legend placement
  legWidth - available width for legend content
Method Details
- placeComments
  int placeComments()
  Lays out every valid graph comment as one or more legend lines
  Returns:
  the legend y offset, left just below the block that was placed

Nested Class Summary

Nested classes/interfaces inherited from interface RrdGraphConstants

Field Summary

Fields inherited from interface RrdGraphConstants

Constructor Summary

Method Summary

Methods inherited from class Object

Field Details

gdef

worker

legX

legY

legWidth

interLegendSpace

leading

smallLeading

boxSpace

Constructor Details

Method Details

placeComments