[LOG4J2-2001] StyleConverter.newInstance argument validation is incorrect

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.8.2
• Fix Version/s: 2.9.0
• Component/s: Configurators
• Assignee: Gary D. Gregory
• Reporter: Paul Burrowes
• Created: 03/Aug/17 05:13
• Updated: 21/Aug/17 19:46
• Resolved: 21/Aug/17 19:46

Description

There are three bugs in the argument handling of StyleConverter.newInstance.
Firstly the javadoc says options may be null. It must not be.
Secondly the method doesn't validate that it is not null.
Thirdly it validates that options.length <1 when the subsequent code requires options.length >=2

    /**
     * Gets an instance of the class.
     *
     * @param config
     *            The current Configuration.
     * @param options
     *            pattern options, may be null. If first element is "short", only the first line of the throwable will
     *            be formatted.
     * @return instance of class.
     */
    public static StyleConverter newInstance(final Configuration config, final String[] options) {
        if (options.length < 1) {
            LOGGER.error("Incorrect number of options on style. Expected at least 1, received " + options.length);
            return null;
        }
        if (options[0] == null) {
            LOGGER.error("No pattern supplied on style");
            return null;
        }
        if (options[1] == null) {
            LOGGER.error("No style attributes provided");
            return null;
        }