microg/GmsCore · error · IllegalStateException

Value is not a map.

Error message

Value is not a map.

What it means

Format guard fired from Value's map operations (e.g. clearKey): the Value's format is not a map format, so per-key mutation is impossible. The calling code assumed a map-typed Value for a field declared with another format.

Source

Thrown at play-services-fitness/src/main/java/com/google/android/gms/fitness/data/Value.java:120

     *
     * @throws IllegalStateException If this {@link Value} does not correspond to a {@link com.google.android.gms.fitness.data.Field#FORMAT_STRING}
     */
    @NonNull
    public String asString() {
        if (format != FORMAT_STRING) throw new IllegalStateException("Value is not a string.");
        if (stringValue == null) return "";
        return stringValue;
    }

    /**
     * Clears any value currently associated with the given {@code key} in the map. This method can be used only on map values.
     *
     * @param key The key you're modifying.
     * @deprecated Use {@link DataPoint.Builder} to construct new {@link DataPoint} instances.
     */
    @Deprecated
    public void clearKey(String key) {
        if (format != FORMAT_MAP) throw new IllegalStateException("Value is not a map.");
        if (mapValue != null) {
            mapValue.remove(key);
        }
    }

    /**
     * Returns the format of this value, which matches the appropriate field in the data type definition.
     *
     * @return One of the format constants from {@link com.google.android.gms.fitness.data.Field}.
     */
    public int getFormat() {
        return format;
    }

    /**
     * Returns the value of the given key in the map as a {@link Float}.
     *
     * @return {@code null} if the key doesn't have a set value in the map.

View on GitHub (pinned to 157c9d86ac)

Solutions

1. Confirm the data type's field is map-formatted before using map methods
2. Use the appropriate accessor for the Value's actual format

When it happens

Trigger: Thrown at play-services-fitness/src/main/java/com/google/android/gms/fitness/data/Value.java:120 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of microg/GmsCore@157c9d86ac (2026-09-06). Data as JSON: /api/errors/078fcf0e8727d464. Report an issue: GitHub.