Spring Boot可以在作为Servlet运行时连接到Cassandra但不能作为命令行运行

Question

@Configuration
@SpringBootApplication
@EnableAutoConfiguration
@EnableCaching
@EnableScheduling
public class MyApplication extends SpringBootServletInitializer {

  @Override
  protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
    return application.sources(MyApplication.class);
  }

  public static void main(String[] args) {
    new MyApplication().configure(new SpringApplicationBuilder(MyApplication.class)).run(args);
  }
}

@Configuration
@SpringBootApplication
@EnableAutoConfiguration
public class MigrationRunner implements CommandLineRunner {

  @Autowired
  Session session;

  @Override
  public void run(String[] args)
  {
    MigrationResources mr = new MigrationResources();
    mr.addMigration(...);
    mr.addMigration(...);

    MigrationEngine.withSession(session).migrate(mr);
  }
}

// annotations
public class MyApplication extends SpringBootServletInitializer {

  private final static String MIGRATE_COMMAND = "migrate";

  @Override
  protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
    return application.sources(MyApplication.class);
  }

  public static void main(String[] args) {
    if (args.length > 0 && args[0].equalsIgnoreCase(MIGRATE_COMMAND)) {
      new SpringApplicationBuilder()
          .sources(MigrationRunner.class)
          .run(Arrays.copyOfRange(args, 1, args.length));
    } else {
      new MyApplication().configure(new SpringApplicationBuilder(MyApplication.class)).run(args);
    }
  }
}

问题是，当我使用migratearg执行此操作时，Spring会抛出以下错误：

创建名为“Migration Runner”的bean时出错：通过字段“session”表示的依赖项不满足

创建类路径资源[org/springframework/boot/autoconfigure/data/cassandra/cassandraDataautoconfiguration.class]中定义的名为“session”的bean时出错：调用init方法失败

Answer 1

你要做的就是，

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

你把申请弄得太复杂了。如果您运行myapplication.main，默认情况下它将在端口8080中运行。

额外的好处是，如果您需要从同一个类开始。

@SpringBootApplication
public class MigrationRunner implements CommandLineRunner {

  @Autowired
  Session session;


  public static void main(String[] args) {
        SpringApplication.run(MyApplication.class, args);
  }

  @Override
  public void run(String[] args)
  {
    MigrationResources mr = new MigrationResources();
    mr.addMigration(...);
    mr.addMigration(...);

    MigrationEngine.withSession(session).migrate(mr);
  }
}