public void duplicateProduct(String ownerId, String copyOwnerId, String productId, String copyProductId, String barCode) { ValidationUtil.validateParameterNotNullAndNotEmptyString(copyProductId, COPY_PRODUCT_ID_PARAMETER_NAME); ValidationUtil.validateParameterNotNullAndNotEmptyString(copyProductId, COPY_OWNER_ID_PARAMETER_NAME); String trimCopyProductId = copyProductId.trim(); GJProduct templateProduct = gjProductRepository.requestProduct(ownerId, productId); Owner copyOwner = ownerRepository.requestOwner(copyOwnerId); GJProduct currentProduct = (GJProduct) productService.duplicateProduct(templateProduct, trimCopyProductId, copyOwner, barCode); currentProduct.setSizeDescription(templateProduct.getSizeDescription()); }用@Mock写一个测试方法

假设我们使用 Mockito 框架来进行测试，可以如下编写测试方法：

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.junit.MockitoJUnitRunner;

@RunWith(MockitoJUnitRunner.class)
public class ProductServiceTest {

    @Mock
    private GJProductRepository gjProductRepository;

    @Mock
    private OwnerRepository ownerRepository;

    @Mock
    private ProductService productService;

    @InjectMocks
    private ProductService testedService;

    @Test(expected = IllegalArgumentException.class)
    public void testDuplicateProductWithEmptyCopyProductId() {
        // Arrange
        String ownerId = "testOwnerId";
        String copyOwnerId = "testCopyOwnerId";
        String productId = "testProductId";
        String copyProductId = "";
        String barCode = "testBarCode";

        // Act
        testedService.duplicateProduct(ownerId, copyOwnerId, productId, copyProductId, barCode);

        // Assert: expects an IllegalArgumentException to be thrown
    }

    // TODO: add more test cases for other parameters
}

在上述代码中，我们使用 `@Mock` 注解标记需要模拟的依赖对象，使用 `@InjectMocks` 注解标记被测试的服务对象。然后，我们编写了一个名为 `testDuplicateProductWithEmptyCopyProductId` 的测试方法，该方法测试当 `copyProductId` 参数为空时，是否会抛出 `IllegalArgumentException` 异常。在该测试方法中，我们首先准备好测试数据，然后调用被测试的服务方法，并期望该方法会抛出 `IllegalArgumentException` 异常。如果方法没有抛出异常，测试将会失败。