001package Torello.Java.Function;
002
003/**
004 * Function-Pointer
005 * <SPAN CLASS=TJF>Input:</SPAN> {@code boolean}
006 * <SPAN CLASS=TJF>Output:</SPAN> {@code boolean}.
007 * 
008 * <BR /><BR />
009 * This is similar to Java's {@code IntPredicate}, except it explicity requires a {@code boolean}
010 * type in it's lambda {@code 'test'} method.
011 */
012@FunctionalInterface
013public interface BoolPredicate
014{
015    /**
016     * Evaluates this predicate on the given argument.
017     * <BR /><BR /><EMBED CLASS='external-html' DATA-FILE-ID=FUNC_INTER_METH>
018     *
019     * @param b primitive-{@code boolean} input argument.
020     * @return {@code TRUE} if the input argument matches this predicate, and <B>FALSE</B> otherwise.
021     */
022    public boolean test(boolean b);
023
024    /**
025     * <EMBED CLASS='external-html' DATA-FILE-ID=PRED_AND_METHOD>
026     * @param other A predicate that will be logically-AND'ed with this predicate
027     * @return <EMBED CLASS='external-html' DATA-FILE-ID=PRED_AND_RETURN>
028     * @throws NullPointerException if parameter {@code 'other'} is null.
029     */
030    default BoolPredicate and(BoolPredicate other)
031    {
032        if (other == null)
033            throw new NullPointerException("null has been passed to parameter 'other'");
034
035        return (boolean b) -> this.test(b) && other.test(b);
036    }
037
038    /**
039     * <EMBED CLASS='external-html' DATA-FILE-ID=PRED_NEGATE_METHOD>
040     * @return <EMBED CLASS='external-html' DATA-FILE-ID=PRED_NEGATE_RETURN>
041     */
042    default BoolPredicate negate()
043    { return (boolean b) -> ! this.test(b); }
044
045    /**
046     * <EMBED CLASS='external-html' DATA-FILE-ID=PRED_OR_METHOD>
047     * @param other a predicate that will be logically-ORed with this predicate
048     * @return <EMBED CLASS='external-html' DATA-FILE-ID=PRED_OR_RETURN>
049     * @throws NullPointerException if parameter {@code 'other'} is null.
050     */
051    default BoolPredicate or(BoolPredicate other)
052    {
053        if (other == null)
054            throw new NullPointerException("null has been passed to parameter 'other'");
055
056        return (boolean b) -> this.test(b) || other.test(b);
057    }
058}