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The JVM level keep changed to the version that I don't want when building spring project

I am currently in the need to create a Spring project with Java version 8. I have set Java to the version 8 and the JDK is 1.8. However, when I build it - I got this notification
Which indeed turn my Java into 17 in my pom.xml . I tried to change the version from my pom and synced it but when I rebuild my project again I got this error
Upgrading my java version to above 8 is not an option. How to fix this?
//edit:
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>3.0.0</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>demo</description>
<properties>
<java.version>8</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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>com.mysql</groupId>
<artifactId>mysql-connector-j</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>

Spring Boot 3.0.0 requires Java 17 and upwards to be compatible with the new features. If you really want to use Java 1.8 I would suggest downgrading the Spring Boot version to the previous stable version which is 2.7.6

Why JVM cannot find the definition of SpringApplication class?

It might look like a duplicate of this question, but the solutions from it didn't work for me. I am getting an Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/boot/SpringApplication at com.example.demo.Application.main error when I try to run the application using spring-boot. My 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>com.example.blog</groupId>
<artifactId>module-8-16-springboot-webflow-thymeleaf</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
<relativePath />
</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-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.webflow</groupId>
<artifactId>spring-webflow</artifactId>
<version>2.5.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.webflow</groupId>
<artifactId>org.springframework.js</artifactId>
<version>2.0.5.RELEASE</version>
</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-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<!-- And other dependencies -->
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
JDK 1.8 and JRE 8 are installed on the system and worked fine before. I deleted the C:\Users\{username}\.M2\repository\org\springframework\boot directory on the system and forced Maven to reload the dependencies. Then I decompiled the file C:\Users\{username}\.M2\repository\org\springframework\boot\spring-boot\2.0.1.RELEASE\spring-boot-2.0.1.RELEASE.jar and still found it in it has this SpringApplication class that the JVM cannot find. I also explicitly added spring-boot-2.0.1.RELEASE.jar to the project, but the error remained the same. There is only a suspicion that I am using Open JDK, and not Oracle, which did not install on the system, but simply downloaded the deployed files and placed them in the folder I needed (the JDK installer for some reason does not work for me). Does anyone have any suggestions on what this problem may be related to?

Problem creating Spring framework project in IntelliJ

I am trying to create a Spring project using Spring initializer in IntelliJ ultimate edition according to the official guide of Jetbrains.
All steps go fine including installing the dependencies of the project.
But whenever I try to run the app; the error below shows up stating that "package org.springframework.boot does not exist" which is already installed in my dependencies.
I've gone through every related post to this problem but no luck. I would appreciate if anyone can guide me through this to figure out what it is that's going wrong about this.
This is also my pom.xml content provided below:
<?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>2.3.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>15</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>

In the top right side you have got a refresh button to reinitialize the Pom.xml file again. Once maven repositories are all set it will allow you to start the project

Why is adding a dependency with Intellij in the Maven Artifact search not working?

I am trying to set up Spring boot in my project. I am using the #Repository annotation and searching for it using the add dependency pop up in intellij - it is under the org.springframework.stereotype class in release 5.2.8. I click Add as this is the dependency I need and nothing happens.
How do I resolve this issue? Another thing I noticed in my pom.xml file the only Spring boot starter parent version I can add is 2.3.2 and not later versions.
See my pom.xml file below:
<?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://ma––ven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>spring-boot-project-test</artifactId>
<version>1.0-SNAPSHOT</version>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.2.RELEASE</version>
</parent>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.2.8.RELEASE</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
Looking at previous questions I deleted the .m2 directory and will reinstall maven with brew - I'm using Mac OS. I added this snippet directly from the Spring boot example page and it's not resolving the release version. It only resolves version 2.3.2:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
I've also used Spring Initalizer to use version 2.3.4 and I open this project directly in intellij - I am getting the same problem in that it cannot find 2.3.4 spring-boot-starter-parent release.

IntelliJ comes with a bundled maven, so make sure you use the one you actually want(between the installed one and the bundled one) by configuring the Maven settings in IntelliJ. Probably you are using the bundled one by default, so you have to hit the reload button on the maven tab(upper right).

spring initializer in spring boot application

I have generated a spring boot application with spring-initializer. when im building the project it gives an unknown error in pom.xml file.
Why is this happening and how to reslove it?error with the 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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.5.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.research</groupId>
<artifactId>patients-api</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>patients-api</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<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>
<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>
</plugins>
</build>

it is not an error to worry about. Spring Boot 2.1.5.RELEASE has release just a week back and probably the IDE you are using for example STS may not be the latest one.
You have 2 options:
update your IDE & Maven and to the latest version [OR]
Simply change version <version>2.1.5.RELEASE</version> to <version>2.1.4.RELEASE</version> and do a Maven update on the project.
I had a similar issue and I fixed with the above options.
Hope this helps.