@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Annotation)) return false;

        Annotation that = (Annotation) o;
        if (!type.equals(that.type)) return false;
        if (spanNode != null ? !spanNode.equals(that.spanNode) : that.spanNode != null) return false;
        if (value != null ? !value.equals(that.value) : that.value != null) return false;

        return true;
    }
Returns true if this Annotation has a value.

@return true if this Annotation has a value, false otherwise.
document/src/main/java/com/yahoo/document/annotation/Annotation.java