Why Your Spring Web Application Refuses to Create an Executable Jar File in IntelliJ IDEA

Are you tired of wrestling with your Spring Web Application, trying to get it to produce an executable jar file in IntelliJ IDEA? You’re not alone! This pesky issue has plagued many developers, and today, we’re going to tackle it head-on. Buckle up, and let’s dive into the world of Spring and IntelliJ IDEA to uncover the secrets behind this frustrating problem.

What’s the Problem, Anyway?

When you create a new Spring Web Application project in IntelliJ IDEA, you expect it to produce an executable jar file, right? After all, that’s what makes it a “web application” in the first place. But sometimes, for reasons unknown, the jar file refuses to materialize. You’ve tried everything: cleaning and rebuilding the project, checking the dependencies, and even performing a ritual dance around your computer (don’t worry, we won’t judge). Still, nothing seems to work.

The Culprits Behind the Problem

Before we dive into the solutions, let’s identify the common culprits behind this issue:

• Incorrect project structure
• Misconfigured dependencies
• Incompatible plugin versions
• Missing or incorrect configuration files
• A combination of the above (because, why not?)

Step 1: Verify Your Project Structure

The first step in troubleshooting this issue is to ensure your project structure is correct. In IntelliJ IDEA, your Spring Web Application project should follow this basic structure:

Project Directory
src
main
java
Resources
webapp
WEB-INF
web.xml
pom.xml (if using Maven) or build.gradle (if using Gradle)

Make sure your project follows this structure, and that all necessary files and directories are present. If you’re using a build tool like Maven or Gradle, ensure that the configuration files (pom.xml or build.gradle) are correctly configured.

Step 2: Check Your Dependencies

Next, let’s examine your project’s dependencies. In IntelliJ IDEA, you can do this by:

1. Opening the Project Structure dialog (File > Project Structure)
2. Navigating to the Modules section
3. Selecting the Dependencies tab

In this tab, you should see a list of dependencies required by your project. Ensure that the following dependencies are included:

Dependency	Description
spring-web	Required for Spring Web Application functionality
spring-webmvc	Required for Spring MVC functionality
javax.servlet-api	Required for Servlet API functionality
tomcat-embed-core	Required for embedded Tomcat server

If any of these dependencies are missing, add them to your project by clicking the “+” button at the top-right corner of the Dependencies tab.

Step 3: Configure Your Build Tool

Now, let’s focus on configuring your build tool. Whether you’re using Maven or Gradle, you’ll need to ensure that the build configuration is correct.

Maven Configuration

In your pom.xml file, add the following configuration:

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

Gradle Configuration

In your build.gradle file, add the following configuration:

plugins {
  id 'org.springframework.boot' version '2.3.0.RELEASE'
  id 'io.spring.dependency-management' version '1.0.9.RELEASE'
  id 'java'
}

group = 'com.example'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '1.8'

repositories {
  mavenCentral()
}

dependencies {
  implementation 'org.springframework.boot:spring-boot-starter-web'
  testImplementation 'org.springframework.boot:spring-boot-starter-test'
}

test {
  useJUnitPlatform()
}

Step 4: Check Your Plugin Versions

Outdated or incompatible plugin versions can also cause issues with creating an executable jar file. Ensure that your plugin versions are up-to-date and compatible with your project:

• Spring Boot Plugin: 2.3.0.RELEASE or higher
• Maven Plugin: 3.6.0 or higher
• Gradle Plugin: 6.7 or higher

In IntelliJ IDEA, you can check your plugin versions by navigating to File > Settings > Plugins.

Step 5: Verify Your Configuration Files

Finally, let’s examine your configuration files. Ensure that your application configuration files (e.g., application.properties or application.yml) are correctly configured and present in the correct location.

application.properties Example

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/mydb
    username: myuser
    password: mypass

Conclusion

By following these steps, you should be able to identify and resolve the issues preventing your Spring Web Application from creating an executable jar file in IntelliJ IDEA. Remember to:

• Verify your project structure
• Check your dependencies
• Configure your build tool
• Check your plugin versions
• Verify your configuration files

With these steps, you’ll be well on your way to creating a successful Spring Web Application that produces an executable jar file. Happy coding!

Bonus Tip: Creating a Runnable Jar File

Once you’ve resolved the issues and created an executable jar file, you can make it runnable by adding the following configuration to your build tool:

<build>
  <plugins>
    <plugin>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-maven-plugin</artifactId>
      <configuration>
        <mainClass>com.example.MyApplication</mainClass>
        <layout>ZIP</layout>
      </configuration>
    </plugin>
  </plugins>
</build>

This will create a runnable jar file that can be executed using the following command:

java -jar target/myapplication.jar

And that’s it! You now have a fully functional Spring Web Application that produces an executable and runnable jar file in IntelliJ IDEA.

Frequently Asked Question

Having trouble getting your Spring Web Application to create an executable jar file in IntelliJ IDEA? Don’t worry, we’ve got you covered!