### Question:
Circuit { @Override public boolean equals(Object object) { if (this == object) { return true; } if (object == null || object.getClass() != getClass()) { return false; } final Circuit other = (Circuit) object; return groups.equals(other.groups) && type == other.type || isSymmetric(other); } Circuit(CircuitType type, String groupIn, String groupOut); CircuitType getType(); String getIn(); String getOut(); @Override int hashCode(); @Override boolean equals(Object object); @Override String toString();  }### Answer:
@Test void testEquals() { final CircuitType type = CircuitType.TOP; final Circuit circuit = new Circuit(type, "a", "a"); assertEquals(circuit, circuit); assertEquals(new Circuit(type, "a", "a"), new Circuit(type, "a", "a")); assertEquals(new Circuit(type, "a", "b"), new Circuit(type, "a", "b")); assertEquals(new Circuit(CircuitType.MIDDLE, "a", "b"), new Circuit(CircuitType.MIDDLE.getSymetric(), "b", "a")); assertEquals(new Circuit(type, "a", "b"), new Circuit(type.getSymetric(), "b", "a")); assertNotEquals(new Circuit(type, "a", "a"), null); assertNotEquals(new Circuit(type, "a", "a"), new Object()); assertNotEquals(new Circuit(type, "a", "b"), new Circuit(type, "b", "a")); assertNotEquals(new Circuit(type, "a", "b"), new Circuit(CircuitType.MIDDLE, "a", "b")); assertNotEquals(new Circuit(type, "a", "b"), new Circuit(type, "a", "a")); assertNotEquals(new Circuit(type, "a", "b"), new Circuit(type, "b", "b")); assertNotEquals(new Circuit(type, "a", "a"), new Circuit(type, "b", "a")); assertNotEquals(new Circuit(type, "a", "a"), new Circuit(type, "b", "b")); assertNotEquals(new Circuit(type, "a", "a"), new Circuit(type.getSymetric(), "b", "b")); }