Spring Boot: does #Entity Annotation exist? - spring

Question

I watched this Spring Boot tutorial: https://javabrains.io/courses/spring_bootquickstart/lessons/Creating-a-Spring-Data-JPA-Repository
and it puts an #Entity annotation before a class name. When I tried to do it in my code, I got an Error saying "can't resolve #Entity".
Here is my pom.xml file:
<?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.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.3.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.eclipse.persistence</groupId>
<artifactId>javax.persistence</artifactId>
<version>2.1.0</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.apache.derby</groupId>
<artifactId>derby</artifactId>
<scope>runtime</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>
</plugins>
</build>
</project>
Do you know what is the problem?

Answer 1

I also faced this problem recently. For me, the spring-boot-starter-data-jpa dependency was the issue. Although it was in the pom.xml file without any errors, but the jars were not there in classpath - even after syncing maven and importing dependencies multiple times in different ways ( mvn clean/update/install).
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
The IDE I was using was IntelliJ Idea.
What worked for me at last : I just put this dependency over all other dependencies inside the <dependencies> ... </dependencies> tag, i.e just changed the order of dependencies and synced. That worked in my case, not sure why.
Below is my pom.xml file contents for reference.
<?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>dev.sanskar.courses</groupId>
<artifactId>course-api</artifactId>
<version>1.0-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.3.RELEASE</version>
</parent>
<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-web</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/javax.persistence/javax.persistence-api -->
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>javax.persistence-api</artifactId>
<version>2.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator -->
<!-- https://mvnrepository.com/artifact/org.hibernate.javax.persistence/hibernate-jpa-2.1-api -->
<!-- https://mvnrepository.com/artifact/org.hibernate.javax.persistence/hibernate-jpa-2.1-api -->
<!-- https://mvnrepository.com/artifact/javax.persistence/persistence-api -->
</dependencies>
<properties>
<java.version>1.8</java.version>
</properties>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

Answer 2

Use spring-boot-starter-data-jpa
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
It works for me ... :)
Do not use the following one
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
</dependency>

Answer 3

I added this dependency
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>javax.persistence-api</artifactId>
</dependency>
Add this and enjoy.

Answer 4

Spring STS usually shows this error when the set up isn't correct.
Go to the line containing the error
Click on the alert bulb so that it can suggest possible fixes
From the options, choose the "Fix project setup"
Follow the rest so that the project then re-aligns the import order.

Answer 5

suppose you have missed a dependency.
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
There are useful sample spring boot projects in this github page.it will be helpful to have a look.

Answer 6

I had the same problem. After I configured the new dependency on pom.xml file, the #Entity annotation is not found because these dependencies is not found. To solve it, the IntelliJ IDE then suggested me to load the Maven changes. On the pom.xml screen, click on the icon to reload Maven.

Answer 7

Make sure you Maven projects are imported successfully.
In the lower right corner of your IntelliJ there will a prompt asking you if you want to import the changes. It will also ask you if you want to enable Auto-Import.

Answer 8

In my case, by adding the spring-boot-starter-data-jpa dependency to the classpath it worked.

Answer 9

Do a force update mvn clean install -U or you can right click on your project -->maven--> update if you are using eclipse/STS. this synchronizes the IDE with pom dependencies.

Answer 10

Seems you are working with EclipseLink JPA implementation,
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>javax.persistence</artifactId>
<version>2.1.0</version>
<scope>compile</scope>
</dependency>
Spring Data JPA works with Hibernate implementation by default. We need to exclude unnecessary Hibernate dependencies from spring-boot-starter-data-jpawhen working with other JPA implementations.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>${spring.version}</version>
<exclusions>
<exclusion>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
</exclusion>
<exclusion>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
</exclusion>
</exclusions>
</dependency>
If you are working with Hibernate, just spring-boot-starter-data-jpa is enough in your case.
I also seen "can't resolve #Entity" issue because of my IDE. In eclipse, click Project option -> Clean the project. This is solved my issue when project dependencies out of sync with IDE.

Answer 11

Click on the red bulb next to the #Entity annotation.
Choose "Add dependency" - choose "javax.persistence.api" (NOT jakarta)

Answer 12

Most of the answers here are hit and try types which doesn't explain why #Entity annotation was not working and why it started working after adding certain dependencies.
Here's how it works-
For using persistence annotations you need to add relevant dependencies with their version, let's say we add spring-boot-starter-data-jpa as follows-
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>2.6.6</version>
</dependency>
Now when you are using Intellij Idea as your IDE, you need to reload your maven project to re read the dependencies from your pom.xml.
Once you do that, #Entity annotation would be available for use.

Answer 13

go to File -> Project Structure -> Project Settings -> Facets in Intellij Idea
click "+" and add "JPA" module

Answer 14

i faced same issue, after add this dependencies fixed my issue
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>javax.persistence-api</artifactId>
</dependency>

Answer 15

What Worked For Me In Last:-
Go To File -> Project Structure -> Modules -> Click On Your Project Name
Then Go To Dependencies click "+" and Then -> Library -> From Maven
Then Search For javax.persistence.api Then Click Ok And Apply Changes

Answer 16

I had the same issues recently and i resolved it using adding this dependency that given below. I think the version change in spring boot made this error, now javax.persistence is not available instead we can use jakarta.persistence
<groupId>org.hibernate</groupId>
<artifactId>hibernate-core</artifactId>
<version>6.1.6.Final</version>
<type>pom</type>
</dependency>

Answer 17

put this in your file at the top as an import statement
import javax.persistence.*;