Intellij maven project Fatal error compiling: invalid flag: --release

Question

I am trying to start with Spring-boot, Maven in Intellij Please help me I am getting the error:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.7.0:compile (default-compile) on project spring-rest: Fatal error compiling: invalid flag: --release -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
Process finished with exit code 1

My pom.xml is:

<?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>spring-rest</artifactId>
       <version>3.1.3.RELEASE</version>
       <packaging>war</packaging>

       <name>spring-rest</name>
       <description>Demo project for Spring Boot</description>

       <parent>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-parent</artifactId>
           <version>2.0.0.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-security</artifactId>
               <version>2.0.0.RELEASE</version>
           </dependency>

         <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter</artifactId>
         </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.hibernate.javax.persistence</groupId>
               <artifactId>hibernate-jpa-2.1-api</artifactId>
               <version>RELEASE</version>
           </dependency>


           <dependency>
               <groupId>mysql</groupId>
               <artifactId>mysql-connector-java</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>

               <plugin>
                   <groupId>org.apache.maven.plugins</groupId>
                   <artifactId>maven-compiler-plugin</artifactId>
                   <version>3.7.0</version>
                   <configuration>
                       <source>1.8</source>
                       <target>1.8</target>
                       <release>8</release>
                       <verbose>true</verbose>
                   </configuration>
               </plugin>
           </plugins>
       </build>

   </project>

Answer 1

In your pom.xml file, simply remove the tag <release>8</release> from your maven-compiler-plugin configuration:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.7.0</version>
    <configuration>
        <source>1.8</source>
        <target>1.8</target>
        <verbose>true</verbose>
    </configuration>
</plugin>

Answer 2

This has to do with the version of JDK running on your system. As per the documentation for maven-compiler-plugin, the release flag is supported since 1.9, and thus has to be commented/removed from the POM if you are using prior (1.8 and below) versions of JDK.

Check Maven documentation for release tag for maven-compiler-plugin here

Answer 3

I faced this problem too, check your JAVA_HOME environment variable. I was setting the value of release to 11 as I am using JAVA 11. My System JAVA_HOME was set for java 8, After adding the JAVA_HOME user environment variable to the java 11 path this got resolved.