How to split up complex conditions and keep short circuit evaluation?

Question

Sometimes conditions can become quite complex, so for readability I usually split them up and give each component a meaningful name. This defeats short-circuit evaluation ho

Answer 1

Your first solution is good for this kind of complexity. If the conditions were more complex, I would write private methods for each check you need to run. Something like:

public class DemoStackOverflow {

    public static void main(String[] args) {
    if ( areValid(args) ) {
        System.out.println("Arguments OK");
    }
    }

    /**
     * Validation of parameters.
     * 
     * @param args an array with the parameters to validate.
     * @return true if the arguments are not null, the quantity of arguments match 
     * the expected quantity and the first and second are not equal; 
     *         false, otherwise.
     */
    private static boolean areValid(String[] args) {
       return notNull(args) && lengthOK(args) && areDifferent(args);
    }

    private static boolean notNull(String[] args) {
       return args != null;
    }

    private static boolean lengthOK(String[] args) {
       return args.length == EXPECTED_ARGS;
    }

    private static boolean areDifferent(String[] args) {
       return !args[0].equals(args[1]);
    }

    /** Quantity of expected arguments */
    private static final int EXPECTED_ARGS = 2;

}