It is a very strange issue. Removing the JSON in TestUtil or the executorService/submit will make the following code working:
import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class ATest {
#BeforeAll
public static void setup(TestInfo test) throws Exception {
}
#Test
void testThis(){
int numThreads = 1;
ExecutorService threadPool = Executors.newFixedThreadPool(numThreads);
threadPool.submit(() -> {
TestUtils.doSomething();
});
}
}
Here is the class with the ObjectMapper>
import com.fasterxml.jackson.databind.ObjectMapper;
public class TestUtils {
private static final ObjectMapper JSON;
static {
JSON = new ObjectMapper();
}
public static void doSomething() {
System.out.println("entered the method");
}
}
Currently, the method doSomething() would not be entered at all.
This issue will be resoved if we trigger the Junit test from Maven or if run it from a static main method.
Related
I am trying to serialise and deserialise a class RuleMessage but can't get it to work. Here is my code:
public class RuleMessage {
private String id;
private SerializableRunnable sRunnable;
public RuleMessage(String id, SerializableRunnable sRunnable) {
this.id = id;
this.sRunnable = sRunnable;
}
}
public interface SerializableRunnable extends Runnable, Serializable {
}
#Test
public void testSerialization() throws JsonProcessingException {
MAPPER.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL,
JsonTypeInfo.As.PROPERTY);
SerializableRunnable r = () -> System.out.println("Serializable!");
RuleMessage rule = new RuleMessage("1", r);
System.out.println(MAPPER.writeValueAsString(businessRule));
}
I am using Java 8. Can someone tell me if this is possible in the Jackson library?
Jackson was created to keep object state not behaviour. This is why it tries to serialise POJO's properties using getters, setters, etc. Serialising lambdas break this idea. Theres is no any property to serialise, only a method which should be invoked. Serialising raw lambda object is really bad idea and you should redesign your app to avoid uses cases like this.
In your case SerializableRunnable interface extends java.io.Serializable which gives one option - Java Serialisation. Using java.io.ObjectOutputStream we can serialise lambda object to byte array and serialise it in JSON payload using Base64 encoding. Jackson supports this scenario providing writeBinary and getBinaryValue methods.
Simple example could look like below:
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
public class JsonLambdaApp {
public static void main(String[] args) throws IOException {
ObjectMapper mapper = new ObjectMapper();
mapper.enable(SerializationFeature.INDENT_OUTPUT);
SerializableRunnable action = () -> System.out.println("Serializable!");
String json = mapper.writeValueAsString(new RuleMessage("1", action));
System.out.println(json);
RuleMessage ruleMessage = mapper.readValue(json, RuleMessage.class);
ruleMessage.getsRunnable().run();
}
}
#JsonSerialize(using = LambdaJsonSerializer.class)
#JsonDeserialize(using = LambdaJsonDeserializer.class)
interface SerializableRunnable extends Runnable, Serializable {
}
class LambdaJsonSerializer extends JsonSerializer<SerializableRunnable> {
#Override
public void serialize(SerializableRunnable value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
try (ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
ObjectOutputStream outputStream = new ObjectOutputStream(byteArrayOutputStream)) {
outputStream.writeObject(value);
gen.writeBinary(byteArrayOutputStream.toByteArray());
}
}
}
class LambdaJsonDeserializer extends JsonDeserializer<SerializableRunnable> {
#Override
public SerializableRunnable deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {
byte[] value = p.getBinaryValue();
try (ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(value);
ObjectInputStream inputStream = new ObjectInputStream(byteArrayInputStream)) {
return (SerializableRunnable) inputStream.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(e);
}
}
}
class RuleMessage {
private String id;
private SerializableRunnable sRunnable;
#JsonCreator
public RuleMessage(#JsonProperty("id") String id, #JsonProperty("sRunnable") SerializableRunnable sRunnable) {
this.id = id;
this.sRunnable = sRunnable;
}
public String getId() {
return id;
}
public SerializableRunnable getsRunnable() {
return sRunnable;
}
}
Above code prints JSON:
{
"id" : "1",
"sRunnable" : "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"
}
and lambda:
Serializable!
See also:
How to serialize a lambda?
How to serialize a lambda function in Java?
First, in RuleMessage you have to either create getters / setters or make the fields public in order to provide Jackson access to the fields.
Your code then prints something like this:
{"#class":"RuleMessage","id":"1","sRunnable":{"#class":"RuleMessage$$Lambda$20/0x0000000800b91c40"}}
This JSON document cannot be deserialized because RuleMessage has no default constructor and the lambda cannot be constructed.
Instead of the lambda, you could create a class:
public class Runner implements SerializableRunnable {
#Override
public void run() {
System.out.println("Serializable!");
}
}
and construct your pojo like this:
new RuleMessage("1", new Runner())
The Jackson deserializer is now able to reconstruct the objects and execute the runner.
I want to write JUnit test case rest controller using mockito framework. I want to know how to write test cases for http request like get and post. Also how to test api which uploads a document.
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyBoolean;
import static org.mockito.ArgumentMatchers.anyString;
import static org.mockito.Mockito.doNothing;
import static org.mockito.Mockito.when;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.fileUpload;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
#RunWith(MockitoJUnitRunner.class)
#WebMvcTest
#AutoConfigureMockMvc
public class ControllerTest {
#Autowired
private MockMvc mvc;
#Mock
Service service;
#InjectMocks
private Controller controller;
#Before
public void setup() {
MockitoAnnotations.initMocks(this);
mvc = MockMvcBuilders.standaloneSetup(marketplaceCatalogController)
.setCustomArgumentResolvers(new PageableHandlerMethodArgumentResolver())
.setViewResolvers(new ViewResolver() {
#Override
public View resolveViewName(String viewName, Locale locale) throws Exception {
return new MappingJackson2JsonView();
}
}).build();
}
#Test
public void testGetMethod() throws Exception {
when(service.getMethod(Mockito.any(SomeClass.class))).thenReturn(new SomeOtherClass);
doNothing().when(service).someMethod();
mvc.perform(get("/get-method").param("paramKey",
"paramValue")).andExpect(status().isOk()).andDo(print());
}
#Test
public void testStatusTnC() throws Exception {
String payload = "{\"key1\": \"value1\", \"key2\": \"value2\"}";
mvc.perform(post("/post-method").content(payload)).andExpect(status().isOk()).andDo(print());
}
#Test
public void testUploadFile() throws Exception {
when(service.uploadSomeContent(any(), any(), anyString(), anyString())).thenReturn(new SomeClass());
mvc.perform(fileUpload("/post-request/uploadFile").file("somefile", "Hello, World!".getBytes()).param("param1", "value1").contentType(MediaType.MULTIPART_FORM_DATA)).andExpect(status().isOk()).andDo(print());
}
}
I'm using HK2 for dependency injection and want to replace a Singleton Object with a Mockito-mock in the context of a JUnit-Test.
The simplest setting would be as follows:
import javax.inject.Inject;
import org.jvnet.hk2.annotations.Service;
#Service
public class A {
#Inject
private B b;
public String test() {
return b.toString();
}
}
#Service
public class B {
public String toString()
{
return "B";
}
}
whereas the JUnit-Test stub is as follows:
import static org.junit.Assert.*;
import javax.inject.Inject;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.jvnet.hk2.testing.junit.HK2Runner;
import org.mockito.Mockito;
import org.mockito.junit.MockitoJUnitRunner;
#RunWith(MockitoJUnitRunner.class)
public class MockTest extends HK2Runner {
private B bMock = Mockito.mock(B.class);
#Inject
private A a;
#Test
public void test() {
Mockito.when(bMock.toString()).thenReturn("Mock");
assertEquals("Mocking worked", "Mock", a.test());
}
}
I want the Mock for B to be injected into A and not the real Object. How can I configure HK2 globally, such that for every instance of B the mock is used?
I already know that I could inject B locally into A by using injection via constructor.
Have you considered using a #Stub of B rather than a Mock?. To do that you can add #Contract onto the implementation of B:
#Service #Contract
public class B {
public String toString()
{
return "B";
}
}
and rather than using the mock use a #Stub:
public class MockTest extends HK2Runner {
#Inject
private A a;
#Test
public void test() {
assertEquals("Mocking worked", "Mock", a.test());
}
#Stub #Rank(1)
public static abstract class BStub extends B {
public String toString() {
return "Mock";
}
}
}
In order for this to work the hk2-metadata-generator should be in the classpath of your test during compilation so it can generate the stub. You put #Rank(1) on the stub to ensure it gets picked over the original B class.
Hope this helps!
I'm new to JUnit and was learning the various annotations. The code below however is giving me output that seems wrong
import static org.junit.Assert.*;
import org.junit.Before;
import org.junit.After;
import org.junit.BeforeClass;
import org.junit.AfterClass;
import org.junit.Test;
public class SampleTest {
#BeforeClass
public static void beforeClass() {
System.out.println("Before Class"); }
#AfterClass
public static void afterClass() {
System.out.println("After Class"); }
#Before
public void before() {
System.out.println("Before"); }
#After
public void after() {
System.out.println("After"); }
#Test
public void testAreFirstAndLastNCharactersTheSame() {
System.out.println("testAreFirstAndLastNCharactersTheSame");}
#Test
public void testTruncateAinFirstNPositions() {
System.out.println("testTruncateAinFirstNPositions"); }
}
The output I get is
Before
testTruncateAinFirstNPositions
After
Before
testAreFirstAndLastNCharactersTheSame
After
Before Class
After Class
This seems wrong as the "Before Class" print should be first. Am I doing something wrong? My Junit version is 4.12. I ran the above piece of code on Intellij.
The actual output screenshot is below
I implemented a runner class A.class inherited from BlockJUnit4ClassRunner so that I can annotate tests with #RunWith(A.class). At the same time, sb. else annotate the tests with RunWith(Parameterized.class). It is obvious we cannot use two #RunWith at the same time.
How to solve this problem? or how to merge these two #RunWith?
I believe this does what you want:
package so.junit.runner;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.model.InitializationError;
import org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters;
import org.junit.runners.parameterized.ParametersRunnerFactory;
import org.junit.runners.parameterized.TestWithParameters;
import java.util.Arrays;
#RunWith(Parameterized.class)
#Parameterized.UseParametersRunnerFactory(CustomParameterizedTest.RunnerFactory.class)
public class CustomParameterizedTest {
#Parameterized.Parameters
public static Iterable<Integer> data() {
return Arrays.asList(new Integer[]{1, 2, 3});
}
private int i;
public CustomParameterizedTest(int i) {
this.i = i;
}
#Test
public void test() {
System.out.println(i);
}
public static class RunnerFactory implements ParametersRunnerFactory {
#Override
public org.junit.runner.Runner createRunnerForTestWithParameters(TestWithParameters test) throws InitializationError {
return new A(test);
}
}
public static class A extends BlockJUnit4ClassRunnerWithParameters {
private final Object[] parameters;
public A(TestWithParameters test) throws InitializationError {
super(test);
parameters = test.getParameters().toArray(new Object[test.getParameters().size()]);
}
#Override
public Object createTest() throws Exception {
return getTestClass().getOnlyConstructor().newInstance(parameters);
}
}
}
Based on the Javadocs in the JUnit Parameterized class, this is how they expect you to create a custom test runner that supports parameterization.
UPDATE
Updated to name the custom runner A