Class WeightMeasurement

java.lang.Object
com.codename1.health.sensors.WeightMeasurement
public final class WeightMeasurement extends Object

A decoded Weight Measurement, characteristic 0x2A9D.

Wire format

Byte 0 is a flags field:

Bit Meaning
0 units: 0 = SI (kg), 1 = Imperial (lb)
1 timestamp present
2 user id present
3 BMI and height present

followed by a uint16 weight and the optional fields.

The resolution depends on the unit

The raw uint16 is scaled by 0.005 kg in SI mode and 0.01 lb in Imperial mode -- not the same multiplier, and not a simple unit conversion applied afterwards. Getting this wrong yields a weight that is wrong by a factor of about two, which is exactly close enough to look plausible. Height carries the same split: 0.001 m against 0.1 in.

Like all characteristics here this one is indicated, not notified.

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    getBmi()
    The body mass index the scale computed, or Double.NaN when absent.
    double
    getHeightMeters()
    The height in metres, or Double.NaN when absent.
    long
    getTimestampMillis()
    The scale's own timestamp in epoch millis, or -1 when absent.
    int
    getUserId()
    The scale's user-profile index, or -1 when absent.
    double
    getWeightKg()
    The weight in kilograms, converted from pounds when the scale reported Imperial units.
    boolean
    hasBmiAndHeight()
    true when this reading carried BMI and height.
    boolean
    isImperial()
    true when the scale transmitted Imperial units.
    static WeightMeasurement
    parse(byte[] value)
    Decodes a 0x2A9D value.
    String
    toString()
    Returns a string representation of the object.

    Methods inherited from class Object

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

  • Method Details

    • parse

      public static WeightMeasurement parse(byte[] value)
      Decodes a 0x2A9D value. Returns null for a malformed or truncated payload; never throws.

    • getWeightKg

      public double getWeightKg()
      The weight in kilograms, converted from pounds when the scale reported Imperial units.

    • isImperial

      public boolean isImperial()
      true when the scale transmitted Imperial units. Useful for matching the user's own display preference; the value returned by getWeightKg() is already normalized either way.

    • getHeightMeters

      public double getHeightMeters()
      The height in metres, or Double.NaN when absent.

    • getBmi

      public double getBmi()
      The body mass index the scale computed, or Double.NaN when absent.

    • hasBmiAndHeight

      public boolean hasBmiAndHeight()
      true when this reading carried BMI and height.

    • getUserId

      public int getUserId()
      The scale's user-profile index, or -1 when absent. Family scales use it to attribute a reading.

    • getTimestampMillis

      public long getTimestampMillis()
      The scale's own timestamp in epoch millis, or -1 when absent.

    • toString

      public String toString()
      Description copied from class: Object
      Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method. The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of: getClass().getName() + '@' + Integer.toHexString(hashCode())
      Overrides:
      toString in class Object