test/jdk/java/awt/geom/AffineTransform/EqualsAndHashCode.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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/**
 * @test
 * @summary Tests that equals(Object) is consistent with hashCode(),
 *          in particular regarding negative versus positive zeros and
 *          NaN values.
 */

import java.awt.geom.AffineTransform;

public class EqualsAndHashCode {
    private static boolean failed;

    public static void main(String arg[]) {
        checkReflexiveEquals();
        checkZeros();
        checkNotEqual();
        if (failed) {
            throw new RuntimeException("Some tests failed.");
        }
    }

    private static void checkReflexiveEquals() {
        AffineTransform t = new AffineTransform(1, 0, 0, 1, Double.NaN, 0);
        if (!t.equals(t)) {
            System.err.println("Transform should be equal to itself.");
            failed = true;
        }
        if (!t.equals(t.clone())) {
            System.err.println("Transform should be equal to its clone.");
            failed = true;
        }
    }

    private static void checkZeros() {
        AffineTransform positive = new AffineTransform(2, 0, 0, 3, 0, +0.0);
        AffineTransform negative = new AffineTransform(2, 0, 0, 3, 0, -0.0);
        if (!positive.equals(negative)) {
            System.err.println("Transforms should be equal despite the sign difference in zero values.");
            failed = true;
        } else if (positive.hashCode() != negative.hashCode()) {
            System.err.println("Equal transforms should have the same hash code value.");
            failed = true;
        }
    }

    private static void checkNotEqual() {
        AffineTransform t1 = new AffineTransform(2, 0, 0, 3, 2, 0);
        AffineTransform t2 = new AffineTransform(2, 0, 0, 3, 2, 4);
        if (t1.equals(t2)) {
            System.err.println("Expected non-equal transforms.");
            failed = true;
        }
        if (t1.hashCode() == t2.hashCode()) {
            System.err.println("Expected different hash codes.");
            failed = true;
        }
    }
}