CODEWITHSUNDEEP
javaspring-bootconstructorlombokdefault-constructor
runnerpaul
runnerpaul

Reputation: 7216

Variable not initialized in default constructor

I have this class:

import lombok.Data;

import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

// tag::code[]
@Data
@Document
public class Image {

    @Id final private String id;
    final private String name;
}
// end::code[]

My understanding is that @Data should create a constructor for all final fields by default. However when I run my application I get this error:

error: variable id not initialized in the default constructor
        @Id final private String id;

Why would this be happening?

Upvotes: 18

Views: 54889

Answers (7)

Dr.Scooby DoobyDoo
Dr.Scooby DoobyDoo

Reputation: 1

this suggestion from Stan worked: Switching from "Processor path" option to "Obtain processors from project classthpath" in "Preferences | Build, Execution, Deployment | Compiler | Annotation Processors -> yourProject"

Upvotes: 0

Đorđe Stanković
Đorđe Stanković

Reputation: 303

I had the same issue and it appears I haven't added the annotationProcessorPath to lombok during it's installation, similar to what @runnerpaul mentioned.

<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>
        <annotationProcessorPaths>
            <path>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>${lombok.version}</version>
            </path>
        </annotationProcessorPaths>
    </configuration>
</plugin>

Upvotes: 17

Oumaima Ben Elhadj Ali
Oumaima Ben Elhadj Ali

Reputation: 11

I used spring initializer to create the project and I added the lombok dependency using it However adding provided to my pom.xml fixed the problem

<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
    <scope>provided</scope>
</dependency>

Upvotes: 1

Stan
Stan

Reputation: 43

I've had a similar issue recently.

Switching from "Processor path" option to "Obtain processors from project classthpath" in "Preferences | Build, Execution, Deployment | Compiler | Annotation Processors -> yourProject" has helped in my case.

The initial value in "Processor path" field contained a path like:

/Users/.../.m2/repository/org/projectlombok/lombok/unknown/lombok-unknown.jar

... which was the root cause of the problem I assume.

correct lombok setup in the IDE

Upvotes: 2

Kyung
Kyung

Reputation: 11

If Still cnt work, you might try select "Obtain processors from project classpath" which is under "Enable annotation processing".

By selecting the "Obtain processors from project classpath" radio button, you ensure that your project uses Lombok's annotation processor from the classpath, which is typically the correct approach when Lombok is added as a Maven or Gradle dependency.

The default option of selecting the "Processor Path" can sometimes cause issues if the path is not correctly resolved or if the Lombok jar file is misplaced. Switching to "Obtain processors from project classpath" resolves such problems since it automatically detects Lombok from the dependencies.

Upvotes: 1

Shekhar Rai
Shekhar Rai

Reputation: 2058

My understanding is that @Data should create a constructor for all final fields by default. Error: variable id not initialized in the default constructor @Id final private String id; Why would this be happening?

Yes! you are right! @Data annotation generates a parameterized constructor for final fields, generates setters for all non-final fields and getters for both types of fields.

In your case, your generated constructor should look like this,

public Image(Long id, String name) {
    this.id = id;
    this.name = name;
}

//getters for both fields

As your constructor not able to initialize the final fields - seems Lombok is not being set up properly - you can verify it by checking your Image.class in the target/classes directory with the same package(as you have it in your src except you have defined the location explicitly through config file). If it's not being generated, verify your dependency, Lombok plugin, you may want to explore Lombok configuration for further set-up.

Upvotes: 8

Dmitry Kononov
Dmitry Kononov

Reputation: 77

You can use @RequiredArgsConstructor

Upvotes: -1

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