@Override
    public boolean equals(Object obj) {
        if (obj == this) return true;
        if (obj == null || obj.getClass() != this.getClass()) return false;
        var that = (ParsedDocumentOperation) obj;
        return Objects.equals(this.operation, that.operation) &&
               this.fullyApplied == that.fullyApplied;
    }
@param operation    the parsed operation
@param fullyApplied true if all the JSON content could be applied,
                    false if some (or all) of the fields were not poresent in this document and was ignored
document/src/main/java/com/yahoo/document/json/ParsedDocumentOperation.java