How to instantiate a service class in a non component class

Question

I have my service class which does a post call. I would like to instantiate that bean/ autowire it to create a object in another class which is not a component or configuration class.

@Service
public class SavePayload {

  // Rest Post Call implementation 

}

    public class PayloadRecord
            implements Record {

        private String payload;

        PayloadProcessor payloadProcessor = new PayloadProcessor();

        public PayloadRecord(String payload) {
            this.payload = payload;
        }

        @SneakyThrows
        @Override
        public boolean isValid() throws ValidationException {
            payloadProcessor.savePayload(payload);
            return true;
        }

        @Override
        public byte[] getBytes(Charset charset) {
            return payload.getBytes(StandardCharsets.UTF_8);
        }

        @Override
        public String getID() {
            return payload;
        }


        @Override
        public String toString() {
            return payload;
        }

        private static class PayloadProcessor {

            @Autowired
            private SavePayload savePayload;

        }

    }

I'm using a template which will do the record processing. As soon as I got message received I'm assigning it to Payload in Payload Record which is non component class. I would like to initialize the SavePayload service. Save payload service is returning null.

Answer 1

Create an application context aware class so you can get the current context, something like:

@Component
public class ContextAwareClass implements ApplicationContextAware {

    private static ApplicationContext ctx;

    public static ApplicationContext getApplicationContext() {
        return ctx;
    }

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) {
        ctx = applicationContext;
    }
}

Then, just get the context and get the bean like:

public class YourRegularNoSpringComponentClass {

    public void doSomething() {
        System.out.println(ContextAwareClass
                .getApplicationContext()
                .getBean("savePayload")
        );
    }
}

Above will print the bean if it exist in your context. In your case you would simple use it rather than print it.

Hope this helps!