001package Torello.Java.Additional;
002
003import java.lang.reflect.Field;
004
005/**
006 * This simple generic-class allows for storing <B STYLE='color:red'>four</B> objects with a 
007 * single reference.
008 *
009 * <EMBED CLASS=globalDefs DATA-KIND=Tuple DATA-N=4>
010 * <EMBED CLASS='external-html' DATA-FILE-ID=MUTABLE_TUPLE>
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 Tuple4<A, B, C, D>
017    extends TupleN
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 field / instance. */
024    public A a;
025
026    /** This holds a pointer to the second field / instance. */
027    public B b;
028
029    /** This holds a pointer to the third field / instance. */
030    public C c;
031
032    /** This holds a pointer to the fourth field / instance. */
033    public D d;
034
035    /** Constructs this object */
036    public Tuple4(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    /** Constructs this object.  Initializes all fields to null. */
045    public Tuple4()
046    {
047        this.a = null;
048        this.b = null;
049        this.c = null;
050        this.d = null;
051    }
052
053    /**
054     * Returns {@code '4'}, indicating how many fields are declared by this class.
055     * @return As an instance of {@code Tuple4}, this method returns {@code '4'};
056     */
057    public int n() { return 4; }
058
059    // Super-class uses this for toString, equals, and hashCode
060    // There is an optimization, so if this is requested multiple times, it is saved in a
061    // transient field.
062
063    final Object[] asArrayInternal()
064    { return new Object[] { a, b, c, d }; }
065
066    public Tuple4<A, B, C, D> clone()
067    { return new Tuple4<>(this.a, this.b, this.c, this.d); }
068
069    /**
070     * <EMBED CLASS=defs DATA-TEXT="Integer, Date, File">
071     * <EMBED CLASS='external-html' DATA-FILE-ID=MULTI_TYPE_EX_COMMON>
072     * <EMBED CLASS='external-html' DATA-FILE-ID=MULTI_TYPE_GET_EXAMPLE>
073     */
074    public Object get(final int i)
075    {
076        // Throws Exception if i not in [1..4]
077        CHECK_GET(i);
078
079        return (i <= 2)
080            ? ((i == 1) ? a : b)
081            : ((i == 3) ? c : d);
082    }
083
084    public Ret4<A, B, C, D> toImmutable()
085    { return new Ret4<>(this.a, this.b, this.c, this.d); }
086}