Java Tests

JavaTests.java

@RunWith(SpringRunner.class)
@DataJpaTest
public class UserEntityTests {

	private static final VehicleIdentificationNumber VIN = new VehicleIdentificationNumber(
			"00000000000000000");

	@Rule
	public ExpectedException thrown = ExpectedException.none();

	@Autowired
	private TestEntityManager entityManager;

	@Test
	public void createWhenUserIdIsNullShouldThrowException() throws Exception {
		this.thrown.expect(IllegalArgumentException.class);
		this.thrown.expectMessage("Username must not be empty");
		new User(null, VIN);
	}

	@Test
	public void createWhenUserIdIsEmptyShouldThrowException() throws Exception {
		this.thrown.expect(IllegalArgumentException.class);
		this.thrown.expectMessage("Username must not be empty");
		new User("", VIN);
	}

	@Test
	public void createWhenVinIsNullShouldThrowException() throws Exception {
		this.thrown.expect(IllegalArgumentException.class);
		this.thrown.expectMessage("VIN must not be null");
		new User("sboot", null);
	}

	@Test
	public void saveShouldPersistData() throws Exception {
		User user = this.entityManager.persistFlushFind(new User("sboot", VIN));
		assertThat(user.getUsername()).isEqualTo("sboot");
		assertThat(user.getVin()).isEqualTo(VIN);
	}

}


@RunWith(SpringRunner.class)
@JsonTest
public class VehicleDetailsJsonTests {

	private JacksonTester<VehicleDetails> json;

	@Test
	public void serializeJson() throws Exception {
		VehicleDetails details = new VehicleDetails("Honda", "Civic");
		assertThat(this.json.write(details)).isEqualTo("vehicledetails.json");
		assertThat(this.json.write(details)).isEqualToJson("vehicledetails.json");
		assertThat(this.json.write(details)).hasJsonPathStringValue("@.make");
		assertThat(this.json.write(details)).extractingJsonPathStringValue("@.make")
				.isEqualTo("Honda");
	}

	@Test
	public void deserializeJson() throws Exception {
		String content = "{\"make\":\"Ford\",\"model\":\"Focus\"}";
		assertThat(this.json.parse(content))
				.isEqualTo(new VehicleDetails("Ford", "Focus"));
		assertThat(this.json.parseObject(content).getMake()).isEqualTo("Ford");
	}

}

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
 
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.test.IntegrationTest;
import org.springframework.boot.test.SpringApplicationConfiguration;
import org.springframework.boot.test.TestRestTemplate;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;
 
import com.fasterxml.jackson.databind.ObjectMapper;
 
@RunWith(SpringJUnit4ClassRunner.class)
// Your spring configuration class containing the @EnableAutoConfiguration
// annotation
@SpringApplicationConfiguration(classes = Application.class)
// Makes sure the application starts at a random free port, caches it throughout
// all unit tests, and closes it again at the end.
@IntegrationTest("server.port:0")
@WebAppConfiguration
public abstract class AbstractIntegrationTest {
 
	// Will contain the random free port number
	@Value("${local.server.port}")
	private int port;
 
	/**
	 * Returns the base url for your rest interface
	 * 
	 * @return
	 */
	private String getBaseUrl() {
		return "http://localhost:" + port;
	}
 
	// Some convenience methods to help you interact with your rest interface
 
	/**
	 * @param requestMappingUrl
	 *            should be exactly the same as defined in your RequestMapping
	 *            value attribute (including the parameters in {})
	 *            RequestMapping(value = yourRestUrl)
	 * @param serviceReturnTypeClass
	 *            should be the the return type of the service
	 * @param parametersInOrderOfAppearance
	 *            should be the parameters of the requestMappingUrl ({}) in
	 *            order of appearance
	 * @return the result of the service, or null on error
	 */
	protected <T> T getEntity(final String requestMappingUrl, final Class<T> serviceReturnTypeClass, final Object... parametersInOrderOfAppearance) {
		// Make a rest template do do the service call
		final TestRestTemplate restTemplate = new TestRestTemplate();
		// Add correct headers, none for this example
		final HttpEntity<String> requestEntity = new HttpEntity<String>(new HttpHeaders());
		try {
			// Do a call the the url
			final ResponseEntity<T> entity = restTemplate.exchange(getBaseUrl() + requestMappingUrl, HttpMethod.GET, requestEntity, serviceReturnTypeClass,
					parametersInOrderOfAppearance);
			// Return result
			return entity.getBody();
		} catch (final Exception ex) {
			// Handle exceptions
		}
		return null;
	}
 
	/**
	 * @param requestMappingUrl
	 *            should be exactly the same as defined in your RequestMapping
	 *            value attribute (including the parameters in {})
	 *            RequestMapping(value = yourRestUrl)
	 * @param serviceListReturnTypeClass
	 *            should be the the generic type of the list the service
	 *            returns, eg: List<serviceListReturnTypeClass>
	 * @param parametersInOrderOfAppearance
	 *            should be the parameters of the requestMappingUrl ({}) in
	 *            order of appearance
	 * @return the result of the service, or null on error
	 */
	protected <T> List<T> getList(final String requestMappingUrl, final Class<T> serviceListReturnTypeClass, final Object... parametersInOrderOfAppearance) {
		final ObjectMapper mapper = new ObjectMapper();
		final TestRestTemplate restTemplate = new TestRestTemplate();
		final HttpEntity<String> requestEntity = new HttpEntity<String>(new HttpHeaders());
		try {
			// Retrieve list
			final ResponseEntity<List> entity = restTemplate.exchange(getBaseUrl() + requestMappingUrl, HttpMethod.GET, requestEntity, List.class, parametersInOrderOfAppearance);
			final List<Map<String, String>> entries = entity.getBody();
			final List<T> returnList = new ArrayList<T>();
			for (final Map<String, String> entry : entries) {
				// Fill return list with converted objects
				returnList.add(mapper.convertValue(entry, serviceListReturnTypeClass));
			}
			return returnList;
		} catch (final Exception ex) {
			// Handle exceptions
		}
		return null;
	}
 
	/**
	 * 
	 * @param requestMappingUrl
	 *            should be exactly the same as defined in your RequestMapping
	 *            value attribute (including the parameters in {})
	 *            RequestMapping(value = yourRestUrl)
	 * @param serviceReturnTypeClass
	 *            should be the the return type of the service
	 * @param objectToPost
	 *            Object that will be posted to the url
	 * @return
	 */
	protected <T> T postEntity(final String requestMappingUrl, final Class<T> serviceReturnTypeClass, final Object objectToPost) {
		final TestRestTemplate restTemplate = new TestRestTemplate();
		final ObjectMapper mapper = new ObjectMapper();
		try {
			final HttpEntity<String> requestEntity = new HttpEntity<String>(mapper.writeValueAsString(objectToPost));
			final ResponseEntity<T> entity = restTemplate.postForEntity(getBaseUrl() + requestMappingUrl, requestEntity, serviceReturnTypeClass);
			return entity.getBody();
		} catch (final Exception ex) {
			// Handle exceptions
		}
		return null;
	}
}

Also note that @TestPropertySource can accept a properties argument to overwrite some property inline, such as @TestPropertySource(properties = "myConf.myProp=valueInTest"), it's useful in case that you don't want a totally brand new property file.
	
@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = ExampleApplication.class)
@TestPropertySource(locations="classpath:test.properties")
public class ExampleApplicationTests {

}

You can use @TestPropertySource to override values in application.properties. From its javadoc:

test property sources can be used to selectively override properties defined in system and application property sources

You can also use meta-annotations to externalize the configuration. For example:

@RunWith(SpringJUnit4ClassRunner.class)
@DefaultTestAnnotations
public class ExampleApplicationTests { 
   ...
}

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
@SpringApplicationConfiguration(classes = ExampleApplication.class)
@TestPropertySource(locations="classpath:test.properties")
public @interface DefaultTestAnnotations { }