### Question:
FieldAndRValue implements Serializable { public RValueExpression getRValue() { return rvalue; } FieldAndRValue();  FieldAndRValue(Path field, RValueExpression rvalue); Path getField(); void setField(Path p); RValueExpression getRValue(); void setRValue(RValueExpression e); @Override String toString(); @Override int hashCode(); @Override boolean equals(Object obj);  }### Answer:
@Test public void testGetRValue() { FieldAndRValue instance = new FieldAndRValue(); RValueExpression expResult = null; RValueExpression result = instance.getRValue(); assertEquals(expResult, result); expResult = new RValueExpression(new Value("X")); instance = new FieldAndRValue(null, expResult); result = instance.getRValue(); assertEquals(expResult, result); }