如何运行两个不同的 spring 启动实例？

Question

I have a need to run two separate spring boot instances, the first instance is responsible for some code-generation, while the second is serves as an API.

Here is the process: 1. Run the generation spring boot app 2. After the generation is shutdown, run the API spring boot app

// Api.java

@Log4j2
@EnableEurekaClient
@SpringBootApplication
public class Api {
    public static void main(String[] args) {
        SpringApplication.run(Api.class, args);
    }
}

// Generator.java
@Log4j2
@EnableEurekaClient
@SpringBootApplication
public class Generator implements CommandLineRunner {

    public static void main(String[] args) {
        SpringApplication.run(Generator.class, args);
        Api.run(args); // run the API instance
    }

    @Override
    public void run(String... args) throws Exception {
        // do generation here
    }
}

Exact error: Error creating bean with name 'nested exception is javax.management.InstanceAlreadyExistsException: org.springframework.boot:type=Admin,name=SpringApplication

The error I'm currently getting is that there is already a spring boot instance, and hence can not call Api.run(args) . I'd like to be able to run both of these one after another. If there is a better way I'm all ears. At the end of the day it needs to be a single runnable jar. My main class is configured to point to the Generation, and theoretically it should generate the code then run the Api.

Answer 1

I use something like this to run 2 services - User Service and Project Service:

    SpringApplicationBuilder uws = new SpringApplicationBuilder(UserWebApplication.class)
            .properties("server.port=8081",
                    "server.contextPath=/UserService");
    uws.run();
    SpringApplicationBuilder pws = new SpringApplicationBuilder(ProjectWebApplication.class)
            .properties("server.port=8082",
                    "server.contextPath=/ProjectService");
    pws.run();

They use different ports and context paths.