Spring Boot Unit Test Simple Example

In this post we will write test cases for a Spring Boot Application. Spring Boot provides a number of utilities and annotations to help test a Spring Boot Application.
Spring Boot Test is provided by two modules -

• spring-boot-test contains core items
• spring-boot-test-autoconfigure supports auto-configuration for tests

spring-boot-starter-test dependency imports both the above Spring Boot test modules as well has JUnit, AssertJ, Hamcrest and a number of other useful libraries.

Lets Begin-

Maven Project will be as follows-



In the Maven we need the spring boot test dependency.Maven will be as follows-

<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.javainuse</groupId>
	<artifactId>SpringBootHelloWorld</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<name>SpringBootHelloWorld</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.4.1.RELEASE</version>
		<relativePath /> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>


		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>

	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>


</project>

Create the SpringBootHelloWorldApplication.java as below-

package com.javainuse;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringBootHelloWorldApplication {

	public static void main(String[] args) {
		SpringApplication.run(SpringBootHelloWorldApplication.class, args);
	}
}

Create the Employee model class as follows-

package com.javainuse.model;

public class Employee {
	private String empId;
	private String name;
	private String designation;
	private double salary;

	public Employee() {
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getDesignation() {
		return designation;
	}

	public void setDesignation(String designation) {
		this.designation = designation;
	}

	public double getSalary() {
		return salary;
	}

	public void setSalary(double salary) {
		this.salary = salary;
	}

	public String getEmpId() {
		return empId;
	}

	public void setEmpId(String empId) {
		this.empId = empId;
	}

}

@RequestMapping maps /employee request to return an employee object.

package com.javainuse.controllers;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.javainuse.model.Employee;

@RestController
public class TestController {

	@RequestMapping(value = "/employee", method = RequestMethod.GET)
	public Employee firstPage() {

		Employee emp = new Employee();
		emp.setName("emp1");
		emp.setDesignation("manager");
		emp.setEmpId("1");
		emp.setSalary(3000);

		return emp;
	}

}

Compile and the run the SpringBootHelloWorldApplication.java as a Java application.
Go to localhost:8080/employee

Next we write JUnit test cases for the TestController.
Define the SpringBootHelloWorldTests.java as follows. Spring Boot provides a @SpringBootTest annotation which can be used as an alternative to the standard spring-test @ContextConfiguration annotation when you need Spring Boot features. The annotation works by creating the ApplicationContext used in your tests via SpringApplication.

package com.javainuse.test;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringBootHelloWorldTests {

	@Test
	public void contextLoads() {
	}

}

Next extend the SpringBootHelloWorldTests.java and write the test case for the TestController.java

package com.javainuse.test;

import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

import org.junit.Before;
import org.junit.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.test.web.servlet.MockMvc;
import org.springframework.test.web.servlet.setup.MockMvcBuilders;
import org.springframework.web.context.WebApplicationContext;

public class TestWebApp extends SpringBootHelloWorldTests {

	@Autowired
	private WebApplicationContext webApplicationContext;

	private MockMvc mockMvc;

	@Before
	public void setup() {
		mockMvc = MockMvcBuilders.webAppContextSetup(webApplicationContext).build();
	}

	@Test
	public void testEmployee() throws Exception {
		mockMvc.perform(get("/employee")).andExpect(status().isOk())
				.andExpect(content().contentType("application/json;charset=UTF-8"))
				.andExpect(jsonPath("$.name").value("emp1")).andExpect(jsonPath("$.designation").value("manager"))
				.andExpect(jsonPath("$.empId").value("1")).andExpect(jsonPath("$.salary").value(3000));

	}

}

Run this TestWebApp class as a JUnit test case.

Download Source Code

Download it -
Spring Boot + Unit Cases

See Also
Spring Boot Hello World Application- Create simple controller and jsp view using Maven
Spring Boot Tutorial-Spring Data JPA
Spring Boot + Simple Security Configuration
Pagination using Spring Boot Simple Example
Spring Boot + ActiveMQ Hello world Example
Spring Boot + Swagger Example Hello World Example
Spring Boot + Swagger- Understanding the various Swagger Annotations
Spring Boot Main Menu
Spring Boot Interview Questions