Communication in Code #1 Priority
Here is a sample of code (happens to be from a test) which I think is not communicative.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | public class ContactNumberTest { final String exampleCountryCode1 = "91"; final String exampleCountryCode2 = "1"; final String exampleNumber1 = "8012345678"; final String exampleNumber2 = "2028569635"; ContactNumber phoneNumberA = new ContactNumber(exampleCountryCode1,exampleNumber1); ContactNumber phoneNumberB = new ContactNumber(exampleCountryCode1,exampleNumber1); ContactNumber phoneNumberC = new ContactNumber(exampleCountryCode2,exampleNumber2); @Test public void testEquals() { //Symmetry assertTrue(phoneNumberA.equals(phoneNumberB)); assertTrue(phoneNumberB.equals(phoneNumberA)); //Reflexivity assertTrue(phoneNumberA.equals(phoneNumberA)); //Not equals assertFalse(phoneNumberA.equals(phoneNumberC)); } @Test public void testHashcode() { assertTrue(phoneNumberA.hashCode() == phoneNumberB.hashCode()); } } |
I know you must be wondering why in the first place someone is writing tests for equals and hashCode. I agree. Its not required. But lets say someone really needs to.
This is how I would refactor the code to make it more communicative.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 | public class ContactNumberTest { private final String indiaCountryCode = "+91"; private final String usCountryCode = "+1"; private final String cellNumber = "8012345678"; private final String mobileNumber = "2028569635"; private final ContactNumber indianNumber = new ContactNumber(indiaCountryCode, cellNumber); private final ContactNumber sameIndianNumber = new ContactNumber(indiaCountryCode, cellNumber); private final ContactNumber usNumber = new ContactNumber(usCountryCode, mobileNumber); private final Map<contactnumber , String> users = new HashMap</contactnumber><contactnumber , String>(); private String userName; @Test public void isSymmetrical() { assertNotSame(indianNumber, sameIndianNumber); assertEquals(indianNumber, sameIndianNumber); assertEquals(sameIndianNumber, indianNumber); } @Test public void isReflexive() { assertEquals(indianNumber, indianNumber); } @Test public void isTransitive() { ContactNumber newIndianNumber = new ContactNumber(indiaCountryCode, cellNumber); assertEquals(indianNumber, sameIndianNumber); assertEquals(sameIndianNumber, newIndianNumber); assertEquals(newIndianNumber, indianNumber); } @Test public void areNotAlwaysEqual() { assertFalse(indianNumber.equals(usNumber)); } @Test public void equalsIsExceptionFree() { assertFalse(indianNumber.equals(null)); } @Test public void isHashFriendly() { addUser("Foo").usingKey(indianNumber); assertEquals("Foo", users.get(indianNumber)); addUser("Bar").usingKey(sameIndianNumber); assertEquals(1, users.size()); } private void usingKey(final ContactNumber number) { users.put(number, userName); } private ContactNumberTest addUser(final String userName) { this.userName = userName; return this; } } </contactnumber> |
