为 DTO 构造函数创建 JUnit 测试

Question

public InventoryTable(String terminalId, String machineType, String machineName) {
        super();
        this.terminalId = terminalId;
        this.machineType = machineType;
        this.machineName = machineName;
    }    

public InventoryTable(InventoryTableDTO inventoryDTO) {
            this.terminalId = inventoryDTO.getTerminalId();
            this.machineType = inventoryDTO.getMachineType();
            this.machineName = inventoryDTO.getMachineName();

        }

Here's my constructors and i need to create a JUnit Test for the second one

Below is my JUnit test for the first constructor

@Before
    public void setUp() {
        inventoryTable = new InventoryTable("12345", "TypeMoTo", "Machina");
        inventoryTable.setTerminalId("12345");
        inventoryTable.setMachineType("TypeMoTo");
        inventoryTable.setMachineName("Machina");
    }

@Test
    public void testThis() {
        assertThat(inventoryTable.getTerminalId()).isEqualTo("12345");
        assertThat(inventoryTable.getMachineType()).isEqualTo("TypeMoTo");
        assertThat(inventoryTable.getMachineName()).isEqualTo("Machina");

    }

Thank you :)

Answer 1

@Before
public void setUp() {
    inventoryTable = new InventoryTable("12345", "TypeMoTo", "Machina");
}
@Test
public void testCopyConstructor() {
    InventoryTable it = new InventoryTable(inventoryTable);
    assertThat(inventoryTable.getTerminalId()).isEqualTo("12345");
    assertThat(inventoryTable.getMachineType()).isEqualTo("TypeMoTo");
    assertThat(inventoryTable.getMachineName()).isEqualTo("Machina");

}

Second constructor is Copy Constructor In setup you already have one instance, so You can pass it to Copy Constructor and asserts values.

Answer 2

Same as you are doing for 1st one, here you can use old object to create new InventoryTable for 2nd constructor.

@Test
public void testThis2() {
   InventoryTable inventoryNew = new InventoryTable();
   assertThat(inventoryNew.getTerminalId()).isEqualTo(inventoryTable.getTerminalId());
   assertThat(inventoryNew.getMachineType()).isEqualTo(inventoryTable.getMachineType());
   assertThat(inventoryNew.getMachineName()).isEqualTo(inventoryTable.getMachineName());  
}

Answer 3

In general you can do:

@Test
public void testSecondConstructor() {
   // setup:
   InventoryTableDTO dto =Mockito.mock(InventoryTableDTO.class);
   Mockito.when(dto.getTerminalId()).thenReturn("12345");
   Mockito.when(dto.getMachineType()).thenReturn("TypeMoTo");
   Mockito.when(dto.getMachineName()).thenReturn("Machina");


   // when:
   InventoryTable underTest = new InventoryTable(dto);

   // then:
   assertThat(inventoryTable.getTerminalId()).isEqualTo("12345");
   assertThat(inventoryTable.getMachineType()).isEqualTo("TypeMoTo");
   assertThat(inventoryTable.getMachineName()).isEqualTo("Machina");

}

Alternatively to creating mock with mockito you can also create InventoryTableDTO with its constructor.

Answer 4

First of all I think that you should just get rid of your @Before because tested object is initialized differently depending on the case and init the cases inside tests. But first also a small change in your 2nd constructor, to use the 1st:

public InventoryTable(InventoryTableDTO inventoryDTO) {
    this(inventoryDTO.getTerminalId(),
        inventoryDTO.getMachineType(),
        inventoryDTO.getMachineName());
}

Tests:

@Test
public void test1st() {
    InventoryTable inventoryTable =
            new InventoryTable("12345", "TypeMoTo", "Machina");        
    assertThat(inventoryTable.getTerminalId()).isEqualTo("12345");
    assertThat(inventoryTable.getMachineType()).isEqualTo("TypeMoTo");
    assertThat(inventoryTable.getMachineName()).isEqualTo("Machina");

}

@Test
public void test2nd() {
    InventoryTable inventoryTable = new InventoryTable(
                new InventorytableDto("12345", "TypeMoTo", "Machina"));
    assertThat(inventoryTable.getTerminalId()).isEqualTo("12345");
    assertThat(inventoryTable.getMachineType()).isEqualTo("TypeMoTo");
    assertThat(inventoryTable.getMachineName()).isEqualTo("Machina");
}