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Spring Java - Parameter 0 of constructor

I'm trying to write a simple CRUD program and I get this error. The program is based after codecademy project. Not sure why I doesn't work.
If I comment out the constructor the error disappears.I don't have anything in my properties.
Can someone give me a hand?
Description:
Parameter 0 of constructor in com.example.FitApp3.controller.FoodController required a bean of type 'com.example.FitApp3.repository.FoodRepository' that could not be found.
Action:
Consider defining a bean of type 'com.example.FitApp3.repository.FoodRepository' in your configuration.
Process finished with exit code 1
This is my code:
Entity/Food.java
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
#Entity
public class Food extends com.example.FitApp3.model.Entity {
private String foodName;
private int foodKcal;
private int foodProtein;
private int foodCarb;
private int foodFat;
public String getFoodName() {
return foodName;
}
public void setFoodName(String foodName) {
this.foodName = foodName;
}
public int getFoodKcal() {
return foodKcal;
}
public void setFoodKcal(int foodKcal) {
this.foodKcal = foodKcal;
}
public int getFoodProtein() {
return foodProtein;
}
public void setFoodProtein(int foodProtein) {
this.foodProtein = foodProtein;
}
public int getFoodCarb() {
return foodCarb;
}
public void setFoodCarb(int foodCarb) {
this.foodCarb = foodCarb;
}
public int getFoodFat() {
return foodFat;
}
public void setFoodFat(int foodFat) {
this.foodFat = foodFat;
}
}
Repository/FoodRepository.java
public interface FoodRepository extends CrudRepository<Food, Integer> {}
Controller/FoodController.java
#RestController
public class FoodController {
private FoodRepository foodRepository;
public FoodController(FoodRepository foodRepository) {
this.foodRepository = foodRepository;
}
}
Mainclass
#SpringBootApplication
public class FitApp3Application {
public static void main(String[] args) {
SpringApplication.run(FitApp3Application.class, args);
System.out.println("hello world");
}
}
pom.xml
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.6.2</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>FitApp3</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>FitApp3</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>17</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>javax.persistence-api</artifactId>
<version>2.2</version>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-commons</artifactId>
<version>2.5.1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>

Can you add #Repository annotation to FoodRepository interface.
#Repository
public interface FoodRepository extends CrudRepository<Food, Integer> {}

You need to replace spring-boot-starter-jdbc with spring-boot-starter-data-jpa as follows:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
You can have a look at the following links the difference between them, but basically, JPA helps you deal with your Database data by mapping it directly to Java objects:
https://www.baeldung.com/jpa-vs-jdbc
JPA or JDBC, how are they different?

I think you are just a little bit confused with spring-jdbc, spring-data and spring persistence interfaces abstraction, let me help. TL;DR solution is at the bottom:
In the constructor of FoodController you are declaring FoodRepository as a parameter, so spring have to find the bean of this time at runtime in order to create bean of FoodController. You have declared FoodRepository and extend it from CrudRepository. I guess, that you have done it with the assumption, that spring will create an implementation of FoodRepository at runtime (because it extends CrudRepository). But, unfortunately, it is not the spring-core module, that will create bean of FoodRepsitory, nor it is spring-jdbc. This interfaces are the part of spring-data project. So, for creation of the bean of the type FoodRepository is responsible current spring-data project in your classpath (I mean, it could be spring-data-jdbc, spring-data-jpa or whatever). This interfaces (CrudRepository, Repository e.t.c.) are common for all of the spring data projects, so they are shipped in spring-data-commons jar, this is why you have them available in classpath, because you have included spring-data-commons explicitly:
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-commons</artifactId>
<version>2.5.1</version>
</dependency>
Another thing is that this starter:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
does not do anything with spring-data project - it just brings spring-jdbc, Hikari connection pool, and some other spring-boot stuff. In other words, the problem is that you do not have any spring-data project in your classpath, thats why FoodRepository bean is not created.
Also note: #Entity does not make sense here, becuase you do not have any jpa persistence provider in classpath
Solution:
To solve the problem, I suggest you to
Remove spring-data-commons dependency from pom.xml
Include spring-boot-starter-data-jpa into your project (into pom.xml). It will bring the appropriate version of spring-data-commons dependency.
Hope it helped, have a nice day!

Add #Repository annotation to FoodRepository interface
and also #Autowired annotation to the FoodRepository in FoodController.

How to prevent #SpringBootScanApplications(scanbase="package") avoiding interfaces?

So I was running a Springboot application then I got this error
***************************
APPLICATION FAILED TO START
***************************
Description:
A component required a bean of type 'sample.ArticledDao' that could not be found.
Action:
Consider defining a bean of type 'sample.ArticledDao' in your configuration.
Then I checked how SpringBoot scans the files and I saw some of the files are ignored
This is how the path looks ( It's not ideal I know) :
This is the code of my Main class :
#SpringBootApplication(scanBasePackages="sample")
#EnableJpaRepositories("sample")
public class Main {
public static void main(String[] args) throws Exception {
SpringApplication.run(Main.class, args);
}
}
This is my ArticlesDao class:
public interface ArticledDao {
List<Articles> findAll();
public void deleteArticles(Articles articles);
}
ArticleSercviceImp class
#Component
public class ArticleSericeImp implements ArticlesServices
{
#Autowired
ArticledDao articleDao;
#Override
public List<Articles> findAll() {
return articleDao.findAll();
}
#Override
public void deleteEmployee(Articles art) {
articleDao.deleteArticles(art);
}
ArticleRepository:
#Repository
public class ArticlesRepository implements ArticledDao{
public ArticlesRepository(NamedParameterJdbcTemplate template) {
this.template = template;
}
NamedParameterJdbcTemplate template;
#Override
public List<Articles> findAll() {
return template.query("select * from article", new ArticlesRowMapper());
}
#Override
public void deleteArticles(Articles articles) {
final String sql = "delete from article where articleid=:articleid";
Map<String,Object> map=new HashMap<String,Object>();
map.put("articleid", articles.getId());
template.execute(sql,map,new PreparedStatementCallback<Object>() {
#Override
public Object doInPreparedStatement(PreparedStatement ps)
throws SQLException, DataAccessException {
return ps.executeUpdate();
}
});
}
}
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.4.5</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>sprinboot_project</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>Sprinboot_Project</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.3.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>5.4.29.Final</version>
</dependency>
</dependencies>
<build>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</pluginManagement>
<resources>
<resource>
<directory>src/main/resources</directory>
<filtering>true</filtering>
</resource>
</resources>
</build>
</project>
I'm new to SpringBoot so I would be very grateful for your help.

I have added the following dependency:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
and removed the spring-data dependency as well (this will bring in all needed transitive dependencies like hibernate etc.).
Then you have excluded the datasource autoconfiguration in your application.properties:
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration
However this auto configuration is needed to autoconfigure the JdbcTemplate, which you use in your ArticleRepository class. So you need to remove that line. With those changes i can get at least to the point where it tries to connect to Postgres (which fails in my case because i don't have a running instance).

The chances are that you're trying to inject the interface into some component, probably some service implementation that looks like this:
#Service
public class ArticleServiceImpl implements ArticeService {
#Autowired
private ArticleDao dao;
....
}
// or alternatively if you're using constructor injection:
#Service
public class ArticleServiceImpl implements ArticeService {
private final ArticleDao dao;
public ArticleServiceImpl(ArticleDao dao) {
this.dao = dao;
}
}
In order to instantiate this service bean, spring needs to resolve its dependencies, which is, in this case, a single dependency of DAO expressed as an interface. So there has to be some real instance that implements that interface ArticleDao.
It seems like you haven't even created such a class, let alone you have to specify it as a bean as well. So spring merely can't find a proper match for injection, hence an error.
To solve this error you should have something like this:
#Repository
public class ArticleDaoImpl implements ArticleDao {
// implement the methods of the interface
}
You might also be using spring data , but its a different story, I assume, the question is about the general spring injection principles...

A component required a bean of type 'sample.ArticledDao' that could not be found.
Spring IoC is trying to make sense of your Bean injections, but Spring cannot find a Bean of type matching sample.ArticledDao. Notice that in your code,
#Repository
public class ArticlesRepository implements ArticledDao
Based on your definition, the ArticledDao bean is not of the ArticledDao type, so it throws an error on
#Component
public class ArticleSericeImp implements ArticlesServices
{
#Autowired
ArticledDao articleDao;
// wrong.
In fact, the ArticledDao bean is of the ArticlesRepository type. Thus, in the consumers, you can autowire either
1.
#Component
public class ArticleSericeImp implements ArticlesServices
{
#Autowired
ArticledDao articlesRepository;
// ...
or,
2.
#Component
public class ArticleSericeImp implements ArticlesServices
{
#Autowired
ArticlesRepository articlesRepository;
// ...

Spring boot Field required a bean of type that could not be found

I'm going through the JPA starter tutorial for spring boot am struggling.
I know the question has been asked sometimes here ('Field required a bean of type that could not be found.' error spring restful API using mongodb)
But those problems are a bit different from what I have.
Structure
java
|
helloWorld
|
web/ -- HelloWorldController
Application
Customer
CustomerRepository
ServletInitializer
As you can see all my packages related to JPA are on the same level as my Application file . According to the tutorial (https://spring.io/guides/gs/accessing-data-jpa/) this should work
My Application class
package helloWorld;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;
import org.springframework.context.annotation.ComponentScan;
#SpringBootApplication
public class Application extends SpringBootServletInitializer {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Autowired
CustomerRepository customerRepository;
#Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
return application.sources(Application.class);
}
}
CustomerRepository
package helloWorld;
import org.springframework.data.repository.CrudRepository;
import java.util.List;
public interface CustomerRepository extends CrudRepository<Customer, Long> {
List<Customer> findByLastName(String lastName);
}
When trying to use #Autowired I receive
***************************
APPLICATION FAILED TO START
***************************
Description:
Field customerRepository in helloWorld.Application required a bean of type 'helloWorld.CustomerRepository' that could not be found.
Action:
Consider defining a bean of type 'helloWorld.CustomerRepository' in your configuration.
Also, adding scanBasePackages={"helloWorld"}) to #SpringBootApplication does not help and from what I read it should also not be needed.
pom.xml:
<?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>helloWorld.com.example</groupId>
<artifactId>helloWorld</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<name>fireCommerce</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.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-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</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>
<plugin>
<groupId>com.microsoft.azure</groupId>
<artifactId>azure-webapp-maven-plugin</artifactId>
<version>1.1.0</version>
<configuration>
<resourceGroup>maven-projects</resourceGroup>
<appName>${project.artifactId}-${maven.build.timestamp}</appName>
<region>westus</region>
<javaVersion>1.8</javaVersion>
<deploymentType>war</deploymentType>
</configuration>
</plugin>
</plugins>
</build>
</project>
link to the github project

You are excluding the autoconfiguration of JPA repositories. Remove the line from application.properties to let Spring make CustomerRepository a bean and configure it.
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration

In my case, I just forgot to add #Component to Impl class of interface!
These errors may be due to absence of one or more stereotype annotations.

I changed this Class Level Annotation from my Application Class.
From:
#SpringBootApplication(exclude = {DataSourceAutoConfiguration.class })
To:
#SpringBootApplication

Try Adding the #ComponentScan("package.path.to.your.repository") annotation above Application class.
- Just make sure your repository is in the the same package path that is written in #ComponentScan
#SpringBootApplication
#ComponentScan("helloworld")
public class Application extends SpringBootServletInitializer {
//your stuff
}

I had the same issue and everything was good except adding the below dependecies.
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>2.4.2</version>
And, It worked for me

you need to add #Repository in repository

At least one JPA metamodel must be present

I am getting this exception while testing my Controller class
Caused by: java.lang.IllegalArgumentException: At least one JPA metamodel must be present!
at org.springframework.util.Assert.notEmpty(Assert.java:450)
at org.springframework.data.jpa.mapping.JpaMetamodelMappingContext.<init>(JpaMetamodelMappingContext.java:54)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:88)
at org.springframework.data.jpa.repository.config.JpaMetamodelMappingContextFactoryBean.createInstance(JpaMetamodelMappingContextFactoryBean.java:43)
at org.springframework.beans.factory.config.AbstractFactoryBean.afterPropertiesSet(AbstractFactoryBean.java:141)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1761)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1698)
My controller test class looks like this
#RunWith(SpringRunner.class)
#WebMvcTest(controllers = {SensorController.class}, secure = false)
public class SensorControllerTest {
#Autowired
private MockMvc mvc;
#MockBean
private SensorService sensorService;
.....
}
My Bootstrap class
#SpringBootApplication(scanBasePackages = "com.javadroider")
#RestController
#EntityScan("com.javadroider.notifier.commons.model")
#EnableJpaRepositories(basePackages = "com.javadroider.notifier")
public class NotifierApplication {
#GetMapping("/")
public String home(){
return "Welcome to Notifier";
}
public static void main(String[] args) {
SpringApplication.run(NotifierApplication.class, args);
}
}
My dependencies look like this
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-rest</artifactId>
<scope>runtime</scope>
</dependency>
</dependencies>
When I remove #EnableJpaRepositories from my Bootstrap class then controller test will be successful. But application will not start. It will fail with NoSuchBeanDefinitionException.
I am not sure if it is something related to the way I have configured my application. All my repository & model classes are in commons module and I am referring to them in my main aplpication.
My query is similar to https://github.com/spring-projects/spring-boot/issues/6844
IllegalArgumentException: At least one JPA metamodel must be present didn't solve my problem

The #WebMvcTest annotation does not auto configure any repositories or JPA layer beans for you because it is primarily focused on testing just the Controller level.
Your main class NotifierApplication is trying to do too much. See the single responsibility principle for good programming practices: https://en.wikipedia.org/wiki/Single_responsibility_principle
The main class should be used just to define your application it should not itself be a #RestController. Create a separate class, NotifierController, for example and make this your #RestController with your endpoints defined there:
#RestController
public class NotifierController {
#GetMapping("/")
public String home(){
return "Welcome to Notifier";
}
}
and keep this separate from your main class:
#SpringBootApplication(scanBasePackages = "com.javadroider")
#EntityScan("com.javadroider.notifier.commons.model")
#EnableJpaRepositories(basePackages = "com.javadroider.notifier")
public class NotifierApplication {
public static void main(String[] args) {
SpringApplication.run(NotifierApplication.class, args);
}
}
The reason it was failing the way you had it is that your WebMvcTest was trying to scan for JPA repositories and entities due to the annotations on the main class but this is not configured for WebMvcTests.

Spring Boot JPA - No qualifying bean of type

I'm learning Spring and things were going well but suddenly running into this issue where it cannot find a qualified bean. Hitting the wall, even in a new app I'm getting this.
Let me know if you need more, going to take a break! I must be missing something very simple.
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException:
No qualifying bean of type [com.alco.repository.ContactRepository]
found for dependency [com.alco.repository.ContactRepository]:
expected at least 1 bean which qualifies as autowire candidate for this dependency.
Dependency annotations: {#org.springframework.beans.factory.annotation.Autowired(required=true)}
My dependencies:
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-rest</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-hateoas</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
Contact class:
package com.example.entity;
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;
#Entity
#AllArgsConstructor
#NoArgsConstructor
#Getter
#Setter
public class Contact implements Serializable {
private static final long serialVersionUID = -1340978779095092824L;
#Id
#GeneratedValue(strategy=GenerationType.AUTO)
private String id;
private String firstName;
private String lastName;
private String address;
private String phoneNumber;
private String email;
}
The simple interface:
package com.alco.repository;
import org.springframework.data.jpa.repository.JpaRepository;
import com.alco.entity.Contact;
public interface ContactRepository extends JpaRepository<Contact, String> {
}

I think you're missing enabling of the JPA repositories:
#ComponentScan(basePackageClasses = ...)
#EntityScan(basePackageClasses = ...)
#EnableAutoConfiguration
#EnableJpaRepositories(basePackageClasses = ...)
public class ... {
}
This would be for your configuration class.

The only thing I can see is this; please try with changing JpaRepository with Repository
import org.springframework.data.repository.Repository
public interface ContactRepository extends Repository<Contact, String> {

You need to annotate your repository with #Repository, otherwise Spring will not manage your Repository class.
Do not use the more generic #Component, as it may lead to different behavior, e.g. in Exception Management. As an example, look at this parte of the Spring Documentation.
Excerpt:
The postprocessor automatically looks for all exception translators
(implementations of the PersistenceExceptionTranslator interface) and
advises all beans marked with the #Repository annotation so that the
discovered translators can intercept and apply the appropriate
translation on the thrown exceptions.
Also, as mentioned here, in the future you might have back-compatibility issues.
As an alternative, you can use #EnableJpaRepositories and specify where Spring should be looking for repositories.