package class9_2_GeneratingHashCodes_051; // Josiah Yoder, MSOE, 04 May 2015

import java.util.HashMap;

public class Complex {
    private int real;
    private int imag;
    private String name = "Bob";

    public Complex(int real, int imag) {
        this.real = real;
        this.imag = imag;
    }

    /**
     * Indicates whether some other object is "equal to" this one.
     *  ...
     * Note that it is generally necessary to override the {@code hashCode}
     * method whenever this method is overridden, so as to maintain the
     * general contract for the {@code hashCode} method, which states
     * that equal objects must have equal hash codes.
     *
     * @param obj the reference object with which to compare.
     * @return true if both real and imaginary parts match.
     * @see #hashCode()
     * @see HashMap
     */
    @Override
    public boolean equals(Object obj) {
        if(!(obj instanceof Complex)) {
            return false;
        } else {
            Complex c = (Complex) obj;
            return this.real == c.real && this.imag == c.imag;
        }
    }

    /**
     * Returns a hash code value for the object. This method is
     * supported for the benefit of hash tables such as those provided by
     * {@link HashMap}.
     * <p>
     * The general contract of {@code hashCode} is:
     * <ul>
     * <li>... must consistently return the same integer, provided no information
     * used in {@code equals} comparisons on the object is modified.
     * <li>If two objects are equal according to the {@code equals(Object)}
     * method, then calling the {@code hashCode} method on each of
     * the two objects must produce the same integer result.
     * <li>It is <em>not</em> required that if two objects are unequal
     * according to the {@link Object#equals(Object)}
     * method, then calling the {@code hashCode} method on each of the
     * two objects must produce distinct integer results.  However, the
     * programmer should be aware that producing distinct integer results
     * for unequal objects may improve the performance of hash tables.
     * </ul>
     * <p>
     *
     * @return a hash code value for this object.
     * @see System#identityHashCode
     */
    @Override
    public int hashCode() {
        return 31*this.real + 19*this.imag + 23*this.name.hashCode();
    }
}