Error creating bean named ‘application’, unable to find default constructor; The nested exception is Java lang.NoSuchMethodException
•
Java
I don't quite understand why this code gives me the error "can't find the default constructor" The constructor is @ Autowired Everything seems to be right Can I help you? thank you
@SpringBootApplication
public class Application {
private ApplicationContext applicationContext;
private MessagingService messagingService;
private Parser parser;
private static final Logger log = LoggerFactory.getLogger(Application.class);
@Autowired
public Application(ApplicationContext applicationContext,MessagingService messagingService,Parser parser)
{
this.applicationContext = applicationContext;
Assert.notNull(messagingService,"MessagingService must not be null");
this.messagingService = messagingService;
Assert.notNull(parser,"Parser must not be null");
this.parser = parser;
}
public static void main (String[] args) {
SpringApplication.run(Application.class,args);
}
@Bean
public CommandLineRunner app() {
return args -> {
Locale defaultLocale = Locale.getDefault();
Locale.setDefault(defaultLocale);
log.info("Using MessagingService: " + messagingService.getMyMessageCode());
parser.parse();
};
}
}
Editing: updated application class
@SpringBootApplication
public class Application {
@Autowired
private MessagingService messagingService;
@Autowired
private Parser parser;
private static final Logger log = LoggerFactory.getLogger(Application.class);
public Application() {}
public static void main (String[] args) {
SpringApplication.run(Application.class,args);
}
@Bean
public CommandLineRunner app() {
return args -> {
Locale defaultLocale = Locale.getDefault();
Locale.setDefault(defaultLocale);
log.info("Using MessagingService: " + messagingService.getMyMessageCode());
parser.parse();
};
}
}
Solution
You cannot automatically load the main spring boot class You can take the dependency injection required by commandlinerunner as the parameter of the method annotated with @ bean, and of course, delete the constructor injection of the main class:
@SpringBootApplication
public class Application {
private static final Logger log = LoggerFactory.getLogger(Application.class);
public static void main (String[] args) {
SpringApplication.run(Application.class,args);
}
@Bean
public CommandLineRunner app(ApplicationContext applicationContext,Parser parser) {
return args -> {
Locale defaultLocale = Locale.getDefault();
Locale.setDefault(defaultLocale);
log.info("Using MessagingService: " + messagingService.getMyMessageCode());
parser.parse();
};
}
}
Edit: correct context configuration after editing:
@SpringBootApplication
public class Application {
private static final Logger log = LoggerFactory.getLogger(Application.class);
public Application() {}
public static void main (String[] args) {
SpringApplication.run(Application.class,args);
}
@Bean
public CommandLineRunner app(MessagingService messagingService,Parser parser) {
return args -> {
Locale defaultLocale = Locale.getDefault();
Locale.setDefault(defaultLocale);
log.info("Using MessagingService: " + messagingService.getMyMessageCode());
parser.parse();
};
}
}
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