info.monitorenter.gui.chart.labelformatters
Class LabelFormatterDate

java.lang.Object
  info.monitorenter.gui.chart.labelformatters.ALabelFormatter
      info.monitorenter.gui.chart.labelformatters.LabelFormatterDate

All Implemented Interfaces:

IAxisLabelFormatter, java.io.Serializable

public class LabelFormatterDate
extends ALabelFormatter
implements IAxisLabelFormatter

An ILabelFormatter instance that uses a DateFormat to format the labels.

Caution:
It only makes sense to use this class if the data of the corresponding axis may be interpreted as long number of milliseconds since the standard base time known as "the epoch", namely January 1, 1970, 00:00:00 GMT.

Caution:
This implementation is not completely conform with the constraint: instance.parse(instance.format(value)) == value This only works for subsequent call: one call to format contains the next value to return from parse to be the same as the format. That value is cached as date / time formatting produces truncation of the internal value (e.g. if no year is displayed).
Use:

 
     Chart2D chart = new <Constructor>
     Axis axis = new AxisSimple();
     axis.setFormatter(new LabelFormatterDate(DateFormat.getDateInstance()));
     chart.setAxisX(axis);
 
 

to use this class.

Version:

$Revision: 1.11 $

Author:

Achim Westermann

See Also:

Date, Serialized Form

Field Summary

Fields inherited from class info.monitorenter.gui.chart.labelformatters.ALabelFormatter

m_propertyChangeSupport, UNIT_UNCHANGED

Fields inherited from interface info.monitorenter.gui.chart.IAxisLabelFormatter

PROPERTY_FORMATCHANGE

Constructor Summary

LabelFormatterDate()
Default constructor that uses the local datetime ( DateFormat.getDateTimeInstance(int, int)) with DateFormat.SHORT style.

LabelFormatterDate(java.text.SimpleDateFormat dateFormat)
Creates a formatter that uses the given date format.

Method Summary

boolean	equals(java.lang.Object obj)
java.lang.String	format(double value) Provide a String for the value.
int	getMaxAmountChars() Returns the maximum amount of characters that will be returned from IAxisLabelFormatter.format(double).
double	getMinimumValueShiftForChange() Returns the minimum change in the value to format that will cause to return a different formatted String.
double	getNextEvenValue(double value, boolean ceiling) Returns the next "even" value to the given one.
int	hashCode()
java.lang.Number	parse(java.lang.String formatted) The reverse operation to IAxisLabelFormatter.format(double).

Methods inherited from class info.monitorenter.gui.chart.labelformatters.ALabelFormatter

addPropertyChangeListener, getAxis, getUnit, initPaintIteration, removePropertyChangeListener, setAxis

Methods inherited from class java.lang.Object

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

Methods inherited from interface info.monitorenter.gui.chart.IAxisLabelFormatter

addPropertyChangeListener, getUnit, initPaintIteration, removePropertyChangeListener, setAxis

Constructor Detail

LabelFormatterDate

public LabelFormatterDate()

Default constructor that uses the local datetime ( DateFormat.getDateTimeInstance(int, int)) with DateFormat.SHORT style.

LabelFormatterDate

public LabelFormatterDate(java.text.SimpleDateFormat dateFormat)

Creates a formatter that uses the given date format.

Parameters:

dateFormat - the date format to use.

Method Detail

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class ALabelFormatter

See Also:

Object.equals(java.lang.Object)

format

public java.lang.String format(double value)

Description copied from interface: IAxisLabelFormatter

Provide a String for the value. Subclasses should override the label formatting here. The raw value is passed here to allow a general treatment. Transformations of this raw value should be done here (e.g. division by multiples of 1000 for scientific unit system display, date formatting,...).

Specified by:

format in interface IAxisLabelFormatter

Parameters:

value - the value to format.

Returns:

the formatted value.

See Also:

IAxisLabelFormatter.format(double)

getMaxAmountChars

public int getMaxAmountChars()

Description copied from class: ALabelFormatter

Returns the maximum amount of characters that will be returned from IAxisLabelFormatter.format(double).

Specified by:

getMaxAmountChars in interface IAxisLabelFormatter

Overrides:

getMaxAmountChars in class ALabelFormatter

Returns:

the maximum amount of characters that will be returned from IAxisLabelFormatter.format(double).

See Also:

IAxisLabelFormatter.getMaxAmountChars()

getMinimumValueShiftForChange

public double getMinimumValueShiftForChange()

Description copied from interface: IAxisLabelFormatter

Returns the minimum change in the value to format that will cause to return a different formatted String.

To achieve two different formatted Strings to be returned from the format method the corresponding values given to the format method have to differ at least by this value.

Some implementations (e.g. a formatter for date) have to use their own format method an increas a value to determine when the first change will occur. This is expensive and it's recommended that this action is performed once only and the result is stored. Additionally this routine has to start with an "even" (see IAxisLabelFormatter.getNextEvenValue(double, boolean)) value to get a correct result (the distance from even number to even number).

Specified by:

getMinimumValueShiftForChange in interface IAxisLabelFormatter

Returns:

the minimum change in the value to format that will cause to return a different formatted String.

See Also:

IAxisLabelFormatter.getMinimumValueShiftForChange()

getNextEvenValue

public double getNextEvenValue(double value,
                               boolean ceiling)

Description copied from interface: IAxisLabelFormatter

Returns the next "even" value to the given one. "Even" means that the format method will exactly return the String for the value and not cut or round any information. A label String created with an "even" number will be exactly at the position it describes.

Specified by:

getNextEvenValue in interface IAxisLabelFormatter

Parameters:

value - the value to get the next "even" value for.

ceiling - if true, the next higher number will returned, else the next lower one.

Returns:

the next "even" value to the given one.

See Also:

IAxisLabelFormatter.getNextEvenValue(double, boolean)

hashCode

public int hashCode()

Overrides:

hashCode in class ALabelFormatter

See Also:

Object.hashCode()

parse

public java.lang.Number parse(java.lang.String formatted)
                       throws java.lang.NumberFormatException

Description copied from interface: IAxisLabelFormatter

The reverse operation to IAxisLabelFormatter.format(double).

The given argument has to be in the format that will be generated by that method or exceptions may be thrown.
test.parse(test.format(d))== d
has to be true if no rounding occurs by the formatter.

Specified by:

parse in interface IAxisLabelFormatter

Parameters:

formatted - a String in the format that will be produced by method IAxisLabelFormatter.format(double).

Returns:

the parsed number.

Throws:

java.lang.NumberFormatException - if the format of the argument is invalid.

See Also:

IAxisLabelFormatter.parse(java.lang.String)