Spring MVC and MongoDB: Unit test with Fongo - returns Null Pointer Exception - spring

Question

I'm working on a Spring, Spring MVC and MongoDB backed application.
I'm looking add an integration test for saving and reading a document file with Fongo.
My test fixture class is the following:
#ActiveProfiles({ "test"})
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = {SpringMongoConfig.class, MockDatasourceConfig.class})
#WebAppConfiguration
public class FSIntegrationFongoTest extends SpringApplicationContextTest {
private MockMvc mockMvc;
#Mock
private FileService fileService;
#Mock
private FileStoreRequest file ;
#Before
#Test
public void setUp() throws IOException {
//set up FongoDB and collection
Fongo fongo = new Fongo("FongoTest");
DB db = fongo.getDB("dbtest");
DBCollection collection = db.getCollection("filedocuments");
//test database
assertNotNull(db);
assertSame("getDB should be idempotent", db, fongo.getDB("dbtest"));
assertEquals(Arrays.asList(db), fongo.getUsedDatabases());
assertEquals(Arrays.asList("dbtest"), fongo.getDatabaseNames());
//test collection
assertNotNull(collection);
assertSame("getCollection should be idempotent", collection, db.getCollection("filedocuments"));
//import json with collection name filedocuments
importJSON("filedocuments", "src/test/resources/SampleFiles.json");
fileService = Mockito.mock(FileServiceImpl.class);
file = Mockito.mock(FileStoreRequest.class);
}
#Test
public void testInsertFileAndGetIt()throws IOException{
FileStoreRequest file = new FileStoreRequest();
file.setId("test1");
file.setFileName("test1");
file.setVersionId("1");
file.setDescription("Test file");
file.setAlias("Testing");
file.setContent(MockUtils.getMockFileContent());
Map<String,String> extraAttributes = new HashMap<>();
extraAttributes.put("parameter1", "parameter1Name");
extraAttributes.put("parameter2", "parameter2Name");
file.setExtraAttributes(extraAttributes);
fileService.storeFileGeneral(file);
System.out.println(file);
assertNotNull(file);
assertEquals("test1", file.getId());
assertEquals("test1", file.getFileName());
//this causes java.lang.NullPointerException
assertEquals(fileService.getFileById("test1").getFileName(), file.getFileName());
}
}
Here down my SpringApplicationContextTest class:
#ActiveProfiles({ "test"})
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(classes = {SpringMongoConfig.class, MockDatasourceConfig.class,})
public class SpringApplicationContextTest {
Logger log = LoggerFactory.getLogger(SpringApplicationContextTest.class);
#Autowired
private MongoTemplate mongoTemplate;
public void importJSON(String collection, String file) {
try {
for (Object line : FileUtils.readLines(new File(file), "utf8")) {
log.debug("Import Object to database:" + line);
mongoTemplate.save(line, collection);
}
} catch (IOException e) {
throw new RuntimeException("Could not import file: " + file, e);
}
}
#Test
public void testContextInitialized() {
assertNotNull(mongoTemplate);
}
}
Here down the project pom.xml file:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<properties>
<spring.version>4.3.3.RELEASE</spring.version>
<hibernate.version>4.1.0.Final</hibernate.version>
<spring.data.version>1.9.0.RELEASE</spring.data.version>
<spring.mongodb.version>1.9.5.RELEASE</spring.mongodb.version>
<apache.commons.io.version>2.5</apache.commons.io.version>
<apache.commons.codec.version>1.10</apache.commons.codec.version>
<apache.commons.fileupload>1.3.2</apache.commons.fileupload>
<tika.version>1.14</tika.version>
<swagger.version>2.6.1</swagger.version>
<jstl.version>1.2</jstl.version>
<javax.servlet.version>3.1.0</javax.servlet.version>
<junit.version>4.12</junit.version>
<hamcrest.version>1.3</hamcrest.version>
<servlet.api.version>2.5</servlet.api.version>
<mockito.version>2.2.15</mockito.version>
<mockwebserver.version>3.8.0</mockwebserver.version>
<jcl.slf4j.version>1.6.0</jcl.slf4j.version>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
<retrofit.version>2.3.0</retrofit.version>
<okhttp.version>3.8.1</okhttp.version>
<slf4jVersion>1.6.1</slf4jVersion>
<nosqlunit-version>0.7.6</nosqlunit-version>
</properties>
<dependencies>
<!-- Spring framework -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>${spring.version}</version>
<exclusions>
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<!-- mongodb java driver -->
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.4.2</version>
</dependency>
<!-- Spring data mongodb -->
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>${spring.mongodb.version}</version>
</dependency>
<dependency>
<groupId>cglib</groupId>
<artifactId>cglib</artifactId>
<version>2.2.2</version>
</dependency>
<!-- Spring controllers -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>${spring.version}</version>
</dependency>
<!-- Apache commons -->
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>${apache.commons.codec.version}</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>${apache.commons.io.version}</version>
</dependency>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>${apache.commons.fileupload}</version>
</dependency>
<!-- Apache tika -->
<dependency>
<groupId>org.apache.tika</groupId>
<artifactId>tika-core</artifactId>
<version>${tika.version}</version>
</dependency>
<!-- Swagger 2.0 -->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>${swagger.version}</version>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>${swagger.version}</version>
</dependency>
<!-- Servlet , JSP, JSTL -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>${jstl.version}</version>
</dependency>
<!-- for compile only, your container should have this -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>${servlet.api.version}</version>
<scope>provided</scope>
</dependency>
<!-- Testing Dependencies -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>${junit.version}</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-core</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-library</artifactId>
<version>${hamcrest.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>${spring.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>${javax.servlet.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-core</artifactId>
<version>${mockito.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>mockwebserver</artifactId>
<version>${mockwebserver.version}</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.jayway.jsonpath</groupId>
<artifactId>json-path-assert</artifactId>
<version>2.2.0</version>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-core</artifactId>
</exclusion>
<exclusion>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.github.fakemongo</groupId>
<artifactId>fongo</artifactId>
<version>1.6.8</version>
</dependency>
<dependency>
<groupId>com.lordofthejars</groupId>
<artifactId>nosqlunit-mongodb</artifactId>
<version>${nosqlunit-version}</version>
<scope>test</scope>
</dependency>
<!-- Jackson Dependencies -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.6.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.6.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.6.3</version>
</dependency>
<!-- Retrofit2 -->
<dependency>
<groupId>com.squareup.retrofit2</groupId>
<artifactId>retrofit</artifactId>
<version>${retrofit.version}</version>
</dependency>
<dependency>
<groupId>com.squareup.retrofit2</groupId>
<artifactId>converter-gson</artifactId>
<version>${retrofit.version}</version>
</dependency>
<dependency>
<groupId>com.squareup.retrofit2</groupId>
<artifactId>converter-jackson</artifactId>
<version>RELEASE</version>
</dependency>
<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>${okhttp.version}</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpasyncclient</artifactId>
<version>4.1.2</version>
</dependency>
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.3</version>
</dependency>
<!-- Bridge logging from JCL to SLF4j-->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>${jcl.slf4j.version}</version>
</dependency>
<!-- Binding for NOP, silently discarding all logging. -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-nop</artifactId>
<version>${slf4jVersion}</version>
</dependency>
</dependencies>
</project>
I get a NullPointerException when running my test fixture:
java.lang.NullPointerException
at com.myproject.fongodb.FSIntegrationFongoTest.testInsertFileAndGetIt(FSIntegrationFongoTest.java:97)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Any clue on what is going wrong?

Answer 1

In your test fixture setUp hook, you are initializing the fileService with a mock object:
fileService = Mockito.mock(FileServiceImpl.class);
Then you are trying to save your file using the mocked object:
fileService.storeFileGeneral(file);
Since the fileService is nothing but a mock, it will do nothing on #storeFileGeneral call and no file will be saved as you are expecting.
Later on, you are trying to read back the persisted file to asset that it has been created using the right id, while all you get is a null reference:
assertEquals(fileService.getFileById("test1").getFileName(), file.getFileName()); // fileService.getFileById("test1") will return 'null'
The short answer would be to review your test fixture since it does not reflect an integration-test since you are testing your FileService behavior.