001package Torello.Java.Additional;
002
003/**
004 * This simple generic-class allows a function to return <B STYLE='color:red'>four</B> objects as a
005 * result, instead of just one.   This is not always so useful, and can make code confusing.
006 * However there are some instances where the only alternative would be to create an entirely new
007 * class/object, when only a single method result would use that object.
008 * 
009 * <EMBED CLASS=globalDefs DATA-KIND=Ret DATA-N=4>
010 * <EMBED CLASS='external-html' DATA-FILE-ID=IMMUTABLE_RET>
011 * @param <A> The type of the <B STYLE='color:red'>first</B> member-field ('{@link #a}').
012 * @param <B> The type of the <B STYLE='color:red'>second</B> member-field ('{@link #b}').
013 * @param <C> The type of the <B STYLE='color:red'>third</B> member-field ('{@link #c}').
014 * @param <D> The type of the <B STYLE='color:red'>last</B> member-field ('{@link #d}').
015 */
016public class Ret4<A, B, C, D>
017    extends RetN
018    implements java.io.Serializable, Cloneable
019{
020    /** <EMBED CLASS='external-html' DATA-FILE-ID=SVUID>  */
021    protected static final long serialVersionUID = 1;
022
023    /** This holds a pointer the first response object. */
024    public final A a;
025
026    /** This holds a pointer to the second response object. */
027    public final B b;
028
029    /** This holds a pointer to the third response object. */
030    public final C c;
031
032    /** This holds a pointer to the fourth response object. */
033    public final D d;
034
035    /** Constructs this object */
036    public Ret4(A a, B b, C c, D d)
037    {
038        this.a = a;
039        this.b = b;
040        this.c = c;
041        this.d = d;
042    }
043
044    /**
045     * Returns {@code '4'}, indicating how many fields are declared by this class.
046     * @return As an instance of {@code Ret4}, this method returns {@code '4'};
047     */
048    public int n() { return 4; }
049
050    // Super-class uses this for toString, equals, and hashCode
051    // There is an optimization, so if this is requested multiple times, it is saved in a
052    // transient field.
053
054    final Object[] asArrayInternal()
055    { return new Object[] { a, b, c, d }; }
056
057    public Ret4<A, B, C, D> clone()
058    { return new Ret4<>(this.a, this.b, this.c, this.d); }
059
060    /**
061     * <EMBED CLASS=defs DATA-TEXT="Integer, Date, File">
062     * <EMBED CLASS='external-html' DATA-FILE-ID=MULTI_TYPE_EX_COMMON>
063     * <EMBED CLASS='external-html' DATA-FILE-ID=MULTI_TYPE_GET_EXAMPLE>
064     */
065    public Object get(final int i)
066    {
067        // Throws Exception if i not in [1..4]
068        CHECK_GET(i);
069
070        return (i <= 2)
071            ? ((i == 1) ? a : b)
072            : ((i == 3) ? c : d);
073    }
074
075    public Tuple4<A, B, C, D> toModifiable()
076    { return new Tuple4<>(this.a, this.b, this.c, this.d); }
077}