Spring Boot Application with Jersey Rest End Points

Yesterday I received a requirement to create a JAVA Spring Boot Application with Jersey Rest end-points. Researching on Internet about how to overwrite the SB configuration I founded that it solves with only one dependency!

So, here is a little example about how to configure and test (with Mockito and EasyMock) a Jersey end-point in a Spring Boot Application.

Steps/Tips

Add the Spring Boot starter Maven dependency for Jersey to your pom.xml

[code language=”xml”]
<!– jersey –>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jersey</artifactId>
</dependency>
[/code]

Add the configuration bean to include the Jersey’s Controller (classes or packages)

[code language=”java”]
package com.example.sb.jersey.config;

import org.glassfish.jersey.server.ResourceConfig;
import org.springframework.context.annotation.Configuration;

import com.example.sb.jersey.controller.ExampleController;

/**
* Configuration class for Jersey controllers.
* @author Gabriel
*
*/
@Configuration
public class JerseyAppConfig extends ResourceConfig {
public JerseyAppConfig() {
// you can map the packages
// packages("com.example.sb.jersey");
// or you can map each controller
register(ExampleController.class);
}
}
[/code]

Replace the default Spring Boot annotations with Jersey annotations for the rest end-points

[code language=”java”]
package com.example.sb.jersey.controller;

import java.util.Map;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Component;

import com.example.sb.jersey.service.ExampleService;

/**
* Handles the resource requests.
* @author Gabriel
*
*/
@Component
@Path("/resources")
public class ExampleController {

private static final Logger LOGGER = LoggerFactory.getLogger(ExampleController.class);

@Autowired
private ExampleService exampleService;

/**
* Gets a list of configured resources (queues and/or topics) for the application.
* @return
*/
@GET
@Produces(MediaType.APPLICATION_JSON_VALUE)
@Path("/get/test")
public ResponseEntity<Map<String,String>> getConfiguredResources() {
LOGGER.info("getConfiguredResources – start");

Map<String,String> configuredResources = exampleService.getConfiguredResources();

LOGGER.info("getConfiguredResources – end");
return new ResponseEntity<Map<String,String>>(configuredResources, HttpStatus.OK);
}
}
[/code]

Unit Test for the Controller with Mockito for Spring Boot 1.4 or higer

[code language=”java”]
package com.example.sb.jersey.controller;

import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;
import org.junit.runner.RunWith;
import org.mockito.Mockito;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.boot.test.mock.mockito.SpyBean;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.test.context.junit4.SpringRunner;

import com.example.sb.jersey.controller.ExampleController;
import com.example.sb.jersey.service.ExampleService;

import static org.hamcrest.MatcherAssert.assertThat;

import java.util.HashMap;
import java.util.Map;

import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.CoreMatchers.equalTo;

@RunWith(SpringRunner.class)
public class ExampleControllerTest {

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

@MockBean
ExampleService exampleServiceMock;

@SpyBean // use inject mocks with spring boot versions lower than 1.4
private ExampleController exampleController;

private Map<String, String> configuredResources;

@Before
public void setUp() {
configuredResources = new HashMap<>();
configuredResources.put("1", "resource #1");
configuredResources.put("2", "resource #2");
configuredResources.put("3", "resource #3");
configuredResources.put("4", "resource #4");
configuredResources.put("5", "resource #5");
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithListOfConfiguredResources() {
Mockito.doReturn(configuredResources).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), notNullValue());
assertThat(result.getBody().size(), equalTo(configuredResources.size()));
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithNullListOfConfiguredResources() {
Mockito.doReturn(null).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), nullValue());
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithEmptyListOfConfiguredResources() {
Mockito.doReturn(new HashMap<>()).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), notNullValue());
assertThat(result.getBody().size(), equalTo(0));
}
}
[/code]

Unit Test for the Controller with Mockito for Spring Boot 1.3.8 or lower

[code language=”java”]
package com.example.sb.jersey.controller.oldmockito;

import org.junit.Before;
import org.junit.Test;
import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.Mockito;
import org.mockito.MockitoAnnotations;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;

import com.example.sb.jersey.controller.ExampleController;
import com.example.sb.jersey.service.ExampleService;

import static org.hamcrest.MatcherAssert.assertThat;

import java.util.HashMap;
import java.util.Map;

import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.CoreMatchers.equalTo;

public class ExampleControllerTest {

@Mock
ExampleService exampleServiceMock;

@InjectMocks // use inject mocks with spring boot versions lower than 1.4
private ExampleController exampleController = new ExampleController();

private Map<String, String> configuredResources;

@Before
public void setUp() {
configuredResources = new HashMap<>();
configuredResources.put("1", "resource #1");
configuredResources.put("2", "resource #2");
configuredResources.put("3", "resource #3");
configuredResources.put("4", "resource #4");
configuredResources.put("5", "resource #5");

MockitoAnnotations.initMocks(this);
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithListOfConfiguredResources() {
Mockito.doReturn(configuredResources).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), notNullValue());
assertThat(result.getBody().size(), equalTo(configuredResources.size()));
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithNullListOfConfiguredResources() {
Mockito.doReturn(null).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), nullValue());
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithEmptyListOfConfiguredResources() {
Mockito.doReturn(new HashMap<>()).when(exampleServiceMock).getConfiguredResources();

ResponseEntity<Map<String,String>> result = exampleController.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.getStatusCode(), equalTo(HttpStatus.OK));
assertThat(result.getBody(), notNullValue());
assertThat(result.getBody().size(), equalTo(0));
}
}
[/code]

Unit Test for the Controller with EasyMock 3.4

[code language=”java”]
package com.example.sb.jersey.service.easymock;

import org.easymock.EasyMockRunner;
import org.easymock.TestSubject;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

import com.example.sb.jersey.service.ExampleService;

import java.util.HashMap;
import java.util.Map;

import static org.hamcrest.CoreMatchers.notNullValue;
import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.MatcherAssert.assertThat;

@RunWith(EasyMockRunner.class)
public class ResourceServiceTest {

@TestSubject
private ExampleService exampleService = new ExampleService();

private Map<String, String> configuredResources;

@Before
public void setUp() {
configuredResources = new HashMap<>();
configuredResources.put("1", "resource #1");
configuredResources.put("2", "resource #2");
configuredResources.put("3", "resource #3");
}

@Test
public void getConfiguredResourcesWithValidArgumentsShouldReturnAResponseEntityWithListOfConfiguredResources() {
Map<String,String> result = exampleService.getConfiguredResources();

assertThat(result, notNullValue());
assertThat(result.size(), equalTo(configuredResources.size()));
}
}
[/code]

 

Final notes
The application was tested with Spring Boot versions: 1.5.3.RELEASE, 1.4.2.RELEASE and 1.3.8.RELEASE (without ServletInitiliazer class)

You can get the complete code from my public GitHub repository. Please, comment or contact me if you have any issue or new ideas about this post.

Also you can find me at Upwork

See you soon with more development notes…