Deploy springboot to WebSphere

I am trying to deploy my spring boot application on WebSphere 9 but is giving me: Error 404: java.io.FileNotFoundException: SRVE0190E: File not found: /test

My pom is

<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>3.1.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>17</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-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <image>
                        <builder>paketobuildpacks/builder-jammy-base:latest</builder>
                    </image>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

and my rest is

@RestController
public class restCont {

    @GetMapping("/test")
    public String test() {
        return "test";
    }
}

I deployed it and it was successful but I cant access my rest Api what configurations I should add to be able to have rest on my WebSphere.

Solution

You need to use versions of SpringBoot/Spring and Java compatible with WebSphere V9.

Use Java 8

    <properties>
        <java.version>8</java.version>
    </properties>

Use SpringBoot 2.x / Spring 5

        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.17</version>

NOTE: To use newer versions of Java and SpringBoot 3.x / Spring 6 you can use WebSphere Liberty / Open Liberty, see: https://openliberty.io/blog/2023/09/19/23.0.0.9.html